PULTRUDED ARTICLES AND METHODS FOR MAKING SAME
A structural reinforcement for an article including a carrier (10) that includes: (i) a mass of polymeric material (12) having an outer surface; and (ii) at least one fibrous composite insert (14) or overlay (980) having an outer surface and including at least one elongated fiber arrangement (e.g., having a plurality of ordered fibers). The fibrous insert (14) or overlay (960) is envisioned to adjoin the mass of the polymeric material in a predetermined location for carrying a predetermined load that is subjected upon the predetermined location (thereby effectively providing localized reinforcement to that predetermined location). The fibrous insert (14) or overlay (960) and the mass of polymeric material (12) are of compatible materials, structures or both, for allowing the fibrous insert or overlay to be at least partially joined to the mass of the polymeric material. Disposed upon at least a portion of the carrier (10) may be a mass of activatable material (128). The fibrous insert (14) or overlay (960) may include a polymeric matrix that includes a thermoplastic epoxy.
The present invention relates generally to composite materials, particularly to composites having a thermoplastic epoxy polymer phase, which can be employed in a number of applications, such as in structural reinforcements and/or baffles for use in transportation vehicles.
BACKGROUNDThere is an ongoing effort in many industries to lighten the weight of articles. In many instances, this is achieved by the selection of materials that have a lower density, thinner section thicknesses or both, as compared with prior materials or structures. As a result, there is a potential for the weakening of structures, and the consequent need for stiffening or other structural reinforcement.
In the field of automotive vehicle manufacturing it is common to employ structural reinforcements within cavities of the vehicle body structure. For instance, it has become common to employ within a cavity of the vehicle body structure a relatively rigid molded polymeric carrier that carries an activatable material on one or more of its outer surfaces. For certain activatable materials, upon being activated (e.g., by the heat from a coating bake oven), the activatable material can expand and bond to a surface defining the cavity.
In order to selectively control the properties of the article reinforcement structure, it has been taught to use hybrid reinforcement structures that include a combination of multiple materials for the carrier. See, e.g., United States U.S. Pat. No. 8,430,448, hereby expressly incorporated by reference for all purposes. See also, Patent Cooperation Treaty (PCT) Application No. WO 2010/054194, hereby expressly incorporated by reference for all purposes.
In the automotive vehicle industry, the use of computer modeling (e.g., finite element analysis) has been employed for simulating a vehicle crash, and for modeling how a particular section of a vehicle will respond to the crash. Such modeling can be utilized to determine appropriate locations for the placement of reinforcing structures.
Notwithstanding the above efforts there remains a need for alternative carrier structures. For example, there remains a need for alternative carrier structures that employ a combination of different materials that, even though they are dissimilar, are still generally compatible (e.g., chemically and/or physically compatible) with each other so that they can be joined together without the need for an adhesive, a mechanical fastener, or other means for physically joining two or more different materials. There also remains an ongoing need for alternative carrier structures that employ a combination of different materials that each contains a substantial polymeric portion (e.g., a non-metallic portion) so that weight savings can be attained. There is also a need for polymeric materials that can be combined to increase the overall modulus and flexural strength of a reinforcement, such that it exceeds that of any of the materials on their own. There also remains an ongoing need for alternative carrier structures that employ a combination of different materials that join together at an interface region that is generally continuous with the portions of the carrier defined by the different respective materials. There also remains an ongoing need for an alternative carrier that can employ one or more localized reinforcement regions by use of a particular material within the carrier, and which may be achieved in the absence of a need for a structural feature (e.g., a rib) for imparting additional strength to the localized reinforcement.
Examples of composite structures are illustrated in PCT Publication No. WO2007/008569, U.S. Published Patent Application Nos. 2011/0039470 and 2012/0251663, and U.S. Pat. No. 7,581,932 all incorporated by reference for all purposes. See also, U.S. Pat. Nos. 6,855,652, 7,125,461 and 7,318,873, and U.S. Published Patent Application Nos. 2003/0039792, 2010/0289242, 2011/0278802, and 2009/0202294, incorporated by reference for all purposes.
The present application also is related to and incorporates by reference for all purposes Great Britain Patent Application No. 1318595.4, filed Oct. 21, 2013.
Further to the above, thermoplastic polymers having at least one epoxide group have been described in U.S. Pat. Nos. 5,115,075; 4,438,254; 6,011,111; and PCT Publication No. WO98/14498 (see e.g., pages 3-8) along with illustrative synthesis conditions, all incorporated by reference herein (see also U.S. Pat. Nos. 3,317,471 and 4,647,648, also incorporated by reference herein). Examples of such materials also can be found, without limitation at paragraphs 16-25 of Published U.S. Patent Application No. 2007/0270515 (Chmielewski et al), incorporated by reference for all purposes.
The use of such thermoplastic polymers in a composite material has been disclosed in PCT Publication No. WO/2006/010823 (addressing in situ reaction of an epoxy and an amine after impregnation), incorporated by reference herein. Notwithstanding the above, there remains a need for alternative composite materials. For example, there remains a need for composite materials that are suitable for use in a carrier for a baffle and/or structural reinforcement for a transportation vehicle of a type exemplified in the above discussed patent publications. For example, in instances where it may be desirable to locally alter or improve a property of a carrier material there remains a need for alternative materials suitable for such purpose. There also remains a need for materials that allow for recycling, reclamation and/or re-use beyond the useful life of the material in its intended application. See also, U.S. Patent Application No. 2009/0298974 (incorporated by reference).
SUMMARY OF THE INVENTIONOne or more of the above needs are met by the present teachings which contemplate improved structures and methods that can be employed advantageously for sealing, baffling and/or structurally reinforcing various articles, and particularly for structurally reinforcing transportation vehicles, such as automotive vehicles. The materials of the present teachings also find application in a number of other applications as will be gleaned from the following discussion. That is, the present teachings relate generally to composite materials, and more particularly to fibrous composite materials that employ a distributed phase (e.g., a fibrous phase) and a thermoplastic polymeric material (e.g., a reformable resin, a thermoplastic reaction product) having at least one epoxide group. The material offers the benefit of mechanical properties typically achieved through the use of thermoset polymeric materials (e.g., thermoset epoxy material) as some or all of a matrix phase of a composite. However, the material has a number of physical attributes that make it suitable for handling, processing and/or post-useful life reclamation, recycling, and/or re-use.
The teachings herein relate to a composite article. The composite article may be in a form suitable for use as part of a baffle and/or structural reinforcement for a transportation vehicle. The composite article may include at least two phases. For example, it may include a distributed phase and a matrix phase within which the distributed phase is distributed. The distributed phase in the composite article may include a plurality of segmented forms selected from fibers, platelets, flakes, whiskers, or any combination thereof. The polymeric matrix in the composite article in which the distributed phase is distributed may include at least about 25% by weight of the polymeric matrix of a substantially thermoplastic polymer having at least one epoxide functional group.
The teachings herein also relate to a method for making a composite article. In general, a method in accordance with the present teachings may employ a step of contacting a plurality of segmented forms provided for defining a distributed phase with a thermoplastic epoxy resin, such as an hydroxy-phenoxyether polymer (e.g., a generally thermoplastic reaction product of an epoxy and an amine) that is in a softened state (e.g., in a liquefied molten state). For instance, a method in accordance with the present teachings may employ forming a composite material by extrusion, injection molding, or a combination of both. Thus, it is envisioned for the teachings herein that there is method of making the composite article that includes contacting an epoxy/amine reaction product material (e.g., a material that is a reaction product of a diepoxide and a primary amine, such as monoethanolamine, or the reaction product of a diepoxide resin (e.g., BPA), a mono primary amine, a di-secondary amine, a dimer captan and/or a di-carboxylic acid); during a step of extrusion, injection molding, pultrusion or any combination thereof. The contacting may be only after the reaction has completed between the epoxy and the amine (e.g., only after the reaction of epoxy and amine). Thus it is possible that the method herein will involve no chemical reaction between any epoxy and amine reactants that occurs with an injection molding machine and/or an extruder. That is, the method may include advancing a thermoplastic polymer having at least one epoxide functional group reaction product along a rotating feed screw within a barrel of a polymeric material shaping apparatus.
The teachings herein provide for a pultruded part comprising: an elongated carrier structure having a first end and a second end; an adhesive disposed along a portion of the carrier structure; at least one connector device adapted for attaching the carrier structure to a vehicle; at least one securing device molded onto the carrier structure; and at least one fastening device molded onto the securing device. The teachings herein also provide for a method of making such a device on an in-line pultrusion system comprising: pulling a plurality of continuous fibers through a die for defining a continuous profile; contacting the plurality of continuous fibers with one or more reactants for forming a continuously forming a polymer for a generally continuous polymeric matrix of the a resulting pultruded article; molding one or more securing devices and fastening devices onto the continuous profile; and extruding a secondary material onto the continuous profile.
Composites that are made in accordance with the present teachings can be employed as some or all of a consolidated fibrous composite material insert and/or overlay. The fibrous material composites herein may include a distributed phase and a matrix phase, wherein the distributed phase includes at least one elongated fiber arrangement in order to define a consolidated fibrous insert for a carrier. The carrier, the consolidated fibrous insert and/or overlay, or each may have an outer surface. The composite, the insert and/or overlay, or each may include at least one elongated fiber arrangement having a plurality of ordered fibers (e.g., organic and/or inorganic fibers) that may be distributed in a predetermined manner in a polymeric material matrix. The polymeric material matrix may include a thermoplastic epoxy resin material as described generally, or as described in any of the particular illustrative materials herein. The composites of the present teachings may be employed alone for defining a carrier for the baffles and/or structural reinforcements of the present teachings. The composites of the present teachings may be employed as a fibrous insert adjoining (e.g., in a manner to achieve as a continuous outer surface) a mass of the polymeric material (e.g., one that includes a polyamide such as Nylon, Nylon 6, Nylon 66, poly-butylene terephthalate, or any combination thereof, optionally being glass filled) for defining such a carrier. The location, size, shape or any combination thereof, of the fibrous insert may be selected to help improve one or more properties of the carrier in the region where the insert is located. The carrier may carry an activatable material over at least a portion of the outer surface of the carrier. For example, the activatable material may be activated by heat (e.g., heat from a paint bake oven, such as an automotive paint bake oven) to foam, expand, adhere and/or cure.
The teachings herein further envision A method comprising pulling a mass of elongated fibers through a die, contacting the mass of elongated fibers with at least two ingredients, with a reaction product of at least two ingredients, or a combination thereof, that infiltrate the mass of elongated fibers and react in situ to form a pultrusion having a thermoplastic polymeric material matrix having a glass transition temperature of less than about 200° C., and assembling the pultrusion with a separate component in the absence of a need for any added adhesive, weld or mechanical fastener.
The surface tension of the mass of elongated fibers may be from about 100 mN/m to about 500 mN/m. The at least two ingredients may include a stoichiometric excess of at least one of the ingredients for making that ingredient available for a subsequent chemical reaction. Another of the at least two ingredients may be provided on a separate component in an amount for reacting with the excess of the first ingredient for forming a chemical bond having a chemistry approximating that of the thermoplastic polymer of the matrix. The thermoplastic polymeric material may include a filler material for increasing the viscosity of the thermoplastic polymeric material. The method may take place under at least a first and second temperature condition, so that the first temperature condition allows a reaction to occur between the at least two ingredients and the second temperature condition allows for infiltration of the at least two ingredients into the mass of elongated fibers. The elongated fibers may be randomly oriented fibers. The elongated fibers may be substantially free of any continuous parallel fibers. The separate component may be electrically conductive.
The teachings herein also provide for a method comprising: providing a composite material having a thermoplastic matrix having a glass transition temperature of less than about 200° C. and at least one reinforcing material dispersed in the thermoplastic matrix; optionally contacting the composite material with at least one electrically conducive material so that the electrically conductive material is dispersed randomly or selectively on or within the composite material; contacting a component to be joined with the composite material; heating the component, the composite material or both to a temperature at which a polymer of the thermoplastic matrix material softens and forms a bond with the component to form an assembly; and cooling the assembly. Upon cooling, the bond remains intact over a temperature range of from about 40° F. to about 180° F.
Also envisioned is a method comprising providing a first component and a second component, introducing a thermoplastic epoxy polymer onto either or both of the first or second component and joining the first component with the second component by way of the thermoplastic epoxy polymer. The first and second component may still be separable.
One or both of first and second component may be a metal. The first and second components may comprise dissimilar materials. One or both of the first or second components may be composites. One or both of the first or second components may comprise a carbon fiber composite. The first and second components may be joined in the absence of heat. The thermoplastic epoxy polymer may be the result of a reaction product of a first ingredient carried on the first component and a second ingredient carried on the second component. One or both of the first and second component may have an electrically conductive filler. The first and second component may be joined by induction heating or welding.
The teachings herein also provide for a method comprising mixing at least two reactants with a plurality of reinforcement elements, reacting the reactants to form a thermoplastic epoxy reaction product having the reinforcing elements dispersed therein, and forming pellets that include the thermoplastic reaction product having the reinforcing elements dispersed therein.
The reinforcing elements may be glass fibers dispersed in an amount of from about 25% by weight to about 80% by weight, from about 30% to about 60% by weight, or even from about 40%-50% by weight. The reactants may be reacted in an extrusion or pultrusion die. The reinforcing elements may have a weight average length of about from about 0.25 to about 3 mils. The method may include extruding or pultruding the pellets. The method may include cooling the material during the extruding or pultruding at the end of a die. The temperature in the die may not exceed 415° F. The method may include contacting the reinforcement elements with an agent for enhancing wetting characteristics and/or rheology of the reaction product. The reinforcing elements may be arranged randomly within the pellets. The method may include injection molding or thermoforming the pellets.
The teachings herein also contemplate a method comprising forming a structure having a continuous profile along its length and having a first shape from a reinforced thermoplastic material formed as a reaction product of an epoxy and an amine, and applying heat and pressure to deform the profile to a second shape. The profile is reinforced by a plurality of fibers arranged in a random orientation which facilitates forming of second shape.
The method may include heating the profile to join to a secondary component. The method may include pultruding the profile. The profile may include a conductive component. The plurality of fibers may mitigate the difference in thermal expansion between the profile and any secondary component attached thereto. The profile may be installed in a vehicle after the vehicle has completed a paint bake oven treatment.
The present teachings meet one or more of the above needs by the improved devices and methods described herein. The explanations and illustrations presented herein are intended to acquaint others skilled in the art with the teachings, its principles, and its practical application. Those skilled in the art may adapt and apply the teachings in its numerous forms, as may be best suited to the requirements of a particular use. Accordingly, the specific embodiments of the present teachings as set forth are not intended as being exhaustive or limiting of the teachings. The scope of the teachings should, therefore, be determined not with reference to the above description, but should instead be determined with reference to the appended claims along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are incorporated by reference for all purposes. Other combinations are also possible as will be gleaned from the following claims, which are also hereby incorporated by reference into this written description.
The present application is related to the teachings of PCT Application No. PCT/U.S.14/070853, filed Dec. 17, 2014; U.S. Provisional Application Ser. No. 61/916,884, filed on Dec. 17, 2013; and PCT Application No. PCT/U.S.14/61531, filed Oct. 21, 2014, the contents of these applications being hereby incorporated by reference for all purposes.
This application claims the benefit of the filing dates of U.S. Provisional Application Ser. No. 62/130,908, filed Mar. 10, 2015; U.S. Provisional Application Ser. No. 62/200,380, filed Aug. 3, 2015; and U.S. Provisional Application Ser. No. 62/296,378, filed Feb. 17, 2016, all of which are incorporated by reference for all purposes.
As noted, the present teachings relate generally to composite materials. In this regard, there are various composites to which the teachings pertain. The composites share the common characteristic that they each employ a fibrous composite material that has a distributed phase (e.g., a fibrous phase) and a thermoplastic polymeric material having at least one epoxide group. The thermoplastic polymeric material haying at least one epoxide group may define a matrix material in which the distributed phase resides. The thermoplastic polymeric material having at least one epoxide group may be hydroxy-phenoxyether polymer, such as a polyetheramine thermoplastic material as described herein. For example, such thermoplastic polymeric material having at least one epoxide group may be a product (e.g., a thermoplastic condensation reaction product) of a reaction of a mono-functional or di-functional species (i.e., respectively, a species having one or two reactive groups, such as an amide containing species), with an epoxide-containing moiety, such as a diepoxide a compound having two epoxide functionalities), reacted under conditions for causing the hydroxyl moieties to react with the epoxy moieties to form a generally linear backbone polymer chain with ether linkages. Examples of the composite structures disclosed herein can be found in U.S. Provisional Application Nos. 62/130,832, filed Mar. 10, 2015; U.S. Provisional Application No. 62/183,380, filed Jun. 23, 2015; U.S. Provisional Application No. 62/294,160, filed Feb. 11, 2016; U.S. Provisional Application No. 62/296,374, Feb. 17, 2016, all incorporated by reference herein for ail purposes. The reformable thermoplastic polymeric material may be formed as a sheet or film and may be substantially free of any distributed (e.g., fibrous) phase, in one non-limiting example, the thermoplastic polymeric material may be formed as a film which may be in contact with a fibrous layer. The reformable thermoplastic polymeric material may be formed as a yarn.
The teachings contemplate the possibility that a structure may be fabricated using a thermoplastic material in accordance with the teachings generally herein. In particular, the structure may be made from a thermoplastic material in accordance with the present teachings that is reinforced with a reinforcement phase. The reinforcement phase may be distributed in a matrix of the thermoplastic material (e.g., a polyamide as described and/or a reformable resin material as described). For example, the reinforcement phase may be at least a majority (by volume) of the total material. It may be greater than about 60% by volume or greater than about 70% by volume. It may be below about 90% by volume, below about 80% by volume, or below about 70% by volume. Any reinforcement phase may be distributed randomly, generally uniformly, and/or in one or more predetermined locations of an article.
The fibrous composite materials may be employed as a portion of another composite material. For example it may be employed as an insert (e.g., a fibrous insert) and/or an overlay of a composite that includes one or more other materials.
The teachings herein relate to a composite article. The composite article may be in a form suitable for use as part of a baffle and/or structural reinforcement for a transportation vehicle. The composite article may be in a form suitable for use as a panel structure. The composite article may be in a form suitable for use as a building construction material, as a furniture material, as a sporting good material (e.g., for skis, snowboards, bicycles, bats, tennis rackets or the like) or as protective gear material (e.g., for police shields, armored vehicle panels, or the like). The fibrous composite materials of any composite article herein may include a single phase or may include at least two phases. The fibrous composite materials of any composite article herein may include at least two phases. For example, it may include a distributed phase and a matrix phase within which the distributed phase is distributed. The distributed phase in the composite article may include a plurality of elongated (e.g., in a ratio of at least 2:1 as between a major and minor dimension of the form) segmented forms selected from fibers, platelets, flakes, whiskers, or any combination thereof. For fibers employed herein, the fibers may be employed in the distributed phase is in the form of a random distribution, a weave, a non-woven mat, a plurality of generally axially aligned fibers (e.g., a tow), a plurality of axially intertwined fibers (e.g., a yarn) or any combination thereof. A plurality of individual fibers may thus be in a generally ordered relationship (e.g., according to a predetermined pattern) relative to each other.
The composition of material of the distributed phase may be the same as or different from the composition of the polymeric matrix. For example, it is possible that material of the distributed phase may be a thermoplastic polymer having at least one epoxide functional group as described generally or specifically within the teachings herein. The polymeric matrix material may also be or include a thermoplastic polymer having at least one epoxide functional group as described generally or specifically within the teachings herein.
The ratio by weight of polymeric matrix to the distributed phase may be range from about 1:10 to about 100:1 (e.g., it may range from about 1:5 to about 10:1, about 1:3 to about 5:1, about 1:2 to about 2:1).
The polymeric matrix in the fibrous composite material in which the distributed phase is distributed may include at least about 25%, 33%, 50%, 67%, 85% by weight of the polymeric matrix of a substantially thermoplastic polymer having at least one epoxide functional group. The polymeric matrix of the substantially thermoplastic polymer having at least one epoxide functional group may have less than about 8%, 3%, or even 1% by weight of a polymeric ingredient other than the thermoplastic polymer having at least one epoxide functional group (e.g., the polymeric matrix consists essentially of the thermoplastic polymer having at least one epoxide functional group).
The balance of the material of the fibrous composite material may be the distributed phase. The balance of the material of the composite material may include the distributed phase in addition to another phase and/or material.
The distributed phase may include one, two or more different materials. For instance it may include a single form (e.g., a single elongated segment form), or a plurality of different forms (e.g., a plurality of elongated segment forms). At least about 25%, 33%, 60%, 67%, 85% by weight of the distributed phase may be fibers. The distributed phase may have less than about 5%, 3%, or even 1% by weight of a form other than a fiber. The matrix material may form the end product alone and be substantially free of any distributed phase.
The material of the distributed phase may include an organic material, an inorganic material or a combination of each. The material may be a naturally occurring material (e.g., a rubber, a cellulose, sisal, jute, hemp, or some other naturally occurring material). It may be a synthetic material (e.g., a polymer (which may be a homopolymer, a copolymer, a terpolymer, a blend, or any combination thereof)). It may be a carbon derived material (e.g., carbon fiber, graphite, graphene, or otherwise). The distributed phase may thus include fibers selected from (organic or inorganic) mineral fibers (e.g., glass fibers, such as E-glass fibers, S-class, B-glass or otherwise), polymeric fibers (e.g., an aramid fiber, a cellulose fiber, or otherwise), carbon fibers, metal fibers, natural fibers (e.g., derived from an agricultural source), or any combination thereof. The plurality of elongated fibers may be oriented generally parallel to each other. They may be braided. They may be twisted. Collections of fibers may be woven and/or nonwoven.
The material of the distributed phase may include a plurality of fibers having a length of at least about 1 cm, 3 cm or even 5 cm or longer. Fibers of the distributed phase may have an average diameter of about 1 to about 50 microns (e.g., about 5 to about 25 microns). The fibers may have a suitable sizing coating thereon. The fibers may be present in each layer, or in the fibrous insert generally, in an amount of at least about 20%, 30%, 40% or even 50% by weight. The fibers may be present in each layer, or in the fibrous insert generally, in an amount below about 90%, 80%, or even about 70%, by weight. By way of example, the fibers may be present in each layer, or in the fibrous insert, in an amount of about 50% to about 70 by weight. Fiber contents by weight may be determined in accordance with ASTM D2584-11.
Tapes and/or sheets (e.g., films) for use in one or more of the portions of a fibrous composite material herein may be made by extrusion, pultrusion or otherwise. In this manner, it may be possible to achieve ordering of the fibers in the tapes and/or sheets. The tape and/or sheet may be formed from the thermoplastic polymer material. The tape and/or sheet may include a fibrous phase or may alternatively be substantially free of any fibrous phase. The thermoplastic polymeric material may be formed into fibers which may then form the tape and/or sheet. A method herein may include a step of impregnating a fibrous mass with the material of the polymeric matrix and passing the resulting impregnated material through a die (e.g., a heated die) or other structure having an opening so that the fibrous mass is coated with a generally continuous mass of the material of the polymeric matrix. In this manner, it is also possible to achieve desired ordering of fibers relative to each other. The composite materials may be formed by keyed extrusion, whereby a heat staking process is used to attach a mechanical fastener, which may located into a channel formed during the extrusion process. Alternatively, the fastener may be attached at a location with no channel formation.
The fibrous composite materials of the present teachings may include one or more layers (e.g., they may have 2, 3, 4, 6, or 15 or more layers) that are consolidated in the sense that they include a plurality of individual fibers or other segmented forms of a distributed phase, which are distributed in a cohesive mass of the polymeric matrix material (e.g., a matrix that includes a hydroxy-phenoxyether polymer, such as a polyetheramine thermoplastic material as described herein). For example, the polymer may be a product (e.g., a thermoplastic condensation reaction product) of a reaction of a mono-functional or di-functional species (i.e., respectively, a species having one or two reactive groups, such as an amide containing species), with an epoxide-containing moiety, such as a diepoxide (i.e., a compound having two epoxide functionalities (a diepoxide resin (e.g., BPA), a mono primary amine, a di-secondary amine, a dimer captan and/or a di-carboxylic acid); reacted under conditions for causing the hydroxyl moieties to react with the epoxy moieties to form a generally linear backbone polymer chain with ether linkages. Multiple layers may be consolidated together so that a cohesive mass, including the multiple layers, is formed. The multiple layers may be consolidated so as to form a predetermined shape in the form of a three-dimensional shaped insert. For instance, the fibrous insert may employ a plurality of layers that include a plurality of elongated fibers (e.g., having a length of at least 1 cm, 3 cm or even 5 cm or longer) that are oriented generally parallel or generally unidirectionally to each other and are distributed in a generally continuous polymeric matrix (e.g., in a continuous matrix of the second polymeric material). A shaping operation (e.g., thermoforming, molding, passing through a die, rolling, or otherwise) may be performed.
The fibers of the distributed phase may be present in an amount, a distribution, or both for reinforcing the composite article by the realization of an increase of one or more mechanical properties selected from ultimate tensile strength, elongation, flexural modulus, compression modulus, or otherwise, as compared with the corresponding property of the polymer matrix material alone.
The fibrous composite materials of the present teachings may be such so that the distributed phase is distributed in the polymeric matrix material in an ordered arrangement, in a substantiality homogenous arrangement or both. It is possible that the distributed phase is distributed in the polymeric matrix material in a random arrangement. The individual fibers may be distributed in a predetermined ordered arrangement within the matrix of polymeric material so that at least a portion of the fibers are ordered in their arrangement (e.g., in a generally ordered relationship relative to each other, such as generally parallel or unidirectional or otherwise generally axially aligned), and thus are not randomly distributed in the polymeric matrix material.
Turning in further detail to the materials that may be employed in the present teachings, a variety of materials having thermoplastic thermal characteristics may be suitable. In general, the teachings herein extend also to certain thermoplastic polymers (e.g., polyamides, such as Nylon 6, or Ultratape from BASF). The materials may be employed alone, as a matrix material of a multi-phasic material (e.g., along with a reinforcement phase, such as carbon fibers, glass fibers, polymeric fibers, natural fibers, or some other segmented form, as described elsewhere herein). It may be employed as a layer of a laminate, as core or a sheath of a core/sheath elongated material, as a core or a shell of a core/shell material, or otherwise.
The materials may be thermoplastic in nature so that it is capable of flowing when subjected to a temperature above its glass transition temperature (Tg), and/or a temperature at which it melts. One particular preferred material for use herein is a reformable resin material, and particularly a materiel that broadly contemplates particular ingredients, reactions and reaction products associated with polymers having an epoxide functionality for imparting at least one mechanical characteristic consistent with epoxy thermoset materials, and at least one processing (e.g., elevated temperature processing) characteristic typically associated with thermoplastic materials (e.g., a glass transition temperature); and still more particularly, the present teachings relate to additive manufacturing with a thermoplastic polyether material, such as a thermoplastic epoxy polymer material.
The materials useful in the present teachings (e.g., as a reformable resin material) may have a relatively low glass transition temperature (Tg). It may he possible to have a Tg below about 100° C., below about 90° C., below about 80° C., below about 70° C., below about 65° C., as measured by differential scanning calorimetry according to ASTM E1356-08(2014). The material of the present teachings may have a glass transition temperature as measured by differential scanning calorimetry according to ASTM E1356-08(2014) of at least about 45° C., at least about 55° C., or at least about 60° C. The use of such materials has the ability to enhance productivity substantially. Energy consumption can be reduced. Build times can be shortened. Still, the resulting materials could result in materials having very attractive mechanical and/or self-adhering characteristics that make it attractive for additive manufacturing builds.
As the following also illustrates, the reformable resin material may have a relatively high Tg. It may be possible to have a Tg in excess of about 115° C., or in excess of about 125° C., or in excess of about 135° C. as measured by differential scanning calorimetry according to ASTM E1356-08(2014). The polymer and/or reaction product of the present teachings may have a glass transition temperature as measured by differential scanning calorimetry according to ASTM E1356-08(2014) of below about 200° C., below about 185° C., or below about 170° C. By way of illustration, the polymer and/or reaction product of the present teachings may have a glass transition temperature as measured by differential scanning calorimetry according to ASTM E1356-08(2014) of at least about 120° C., and below about 170° C.
The polymeric material may exhibit one or any combination of the following characteristics: a tensile strength at yield (according to ASTM D638-14) of at least about 15 MPa (e.g., at least about 30 MPa or 45 MPa), a tensile elongation strength at break (according tee ASTM D638-14) of at least about 40 MPa (e.g., at least about 45 or 55 MPa); an elongation at break (according to ASTM D638-14) of at least about 15% (e.g., at least about 20%, 25 or 30%); and/or a tensile modulus of elasticity (according to ASTM D638-14) of at least about 0.5 GPa, (e.g., at least about 1 GPa, 1.8 GPa, or 2.7 GPa).
By way of illustration of various illustrative materials, the following identifies various possible reactions that may be employed for making a reformable resin material.
In general, at present, any reaction suitable for achieving the desired resulting characteristics in a reformable resin material may be employed. At least two reaction approaches are contemplated as within the scope of the present teachings. Either or both in combination may be employed. In a first approach, a reaction is employed to result in a poly(hydroxyaminoether), (PHAE). In a second approach, a reaction is employed to result in a thermoplastic epoxy polymer that is essentially devoid of nitrogen and/or an amine moiety along its backbone.
Exemplary materials may be made with a difunctional epoxy resin and a primary amine or a secondary diamine, e.g., a reaction between diglycidyl ether of bisphenol A and monoethanolamine. For some applications that may require a higher glass transition temperature (Tg), it is contemplated that some or all of the diglycidyl ether of bisphenol A may be replaced by an epoxy monomer with less mobility. Such epoxy monomers may include diglycidylether of fluorene diphenol or 1,6 napthalene diepoxy. Also, it is contemplated that where fire resistance is desired, some or all of the diglycidyl ether of bisphenol A may be replaced by a brominated bisphenol A epoxy resin. In accordance with this approach materials be prepared by reacting a diglycidyl ether of dihydric aromatic compounds such as the diglycidyl ether of bisphenol A, or a diepoxy-functionalized oly(alkylene oxide) or mixture thereof with a primary amine or a secondary diamine or a monoamine functionalized poly(alkylene oxide) or mixture thereof.
Such materials generally have a relatively high flexural strength and modulus, often much higher than typical polyolefins (i.e., polyethylene and polypropylene). Such materials may be melt processable at temperatures such as a temperature above about 70° C. about 85° C. or about 90° C., and/or below about 300° C., about 250° C., about 230° C., or about 210° C. In addition, use of the reformable resin materials described herein for carrier structures provide for improved rigidity and/or improved adhesion when bonded adhesively to another article, e.g., as compared with another traditional polymeric material such as a polyolefin, a polyamide, a polyester, a polyurethane, a polysulfone, or the like.
As the teachings herein illustrate, other epoxide-containing moieties may be employed. Epoxide-containing moieties may include at least one mono-functional epoxide and/or a di-functional epoxide (“diepoxide”). Among the various diepoxides that can be employed in the teachings, there may be a diglycidyl ether of a dihydric phenol (e.g., resorcinol, biphenol or bisphenol A). Any epoxide-containing moiety herein may be an aliphatic and/or an aromatic epoxide.
An illustration of one possible example of such a material may be a reaction product of a diglycidyl ether of a dihydroxy organic compound and an amino, namely one having two amino hydrogens per molecule (e.g., a reaction product of a diglycidyl ether of bisphenol A and a monoethanolamine), as described for example at col. 1, line 4 through col. 2, line 52 in U.S. Pat. No. 3,317,471 (incorporated by reference).
Additional details of suitable reactants and conditions for this first approach can be found in Published U.S. Application No. 20070270515 (see, e.g., paragraphs [00141]-[0025]), U.S. Pat. No. 5,164,472 (see, e.g., cols. 2-4); and U.S. Pat. No. 3,317,471 (see, e.g., col. 1, line 4 through col. 2, line 52), all incorporated by reference.
Referring in more detail to the second approach, without limitation, this approach may be employed in instances when it is desired to employ a material having a relatively high glass transition temperature. One approach envisions a reaction that may include a step of reacting a dihydric phenol or combination of different dihydric phenols with a diepoxide or combination of different diepoxides. The reaction may occur in the presence of a catalyst, (e.g., a catalyst selected from the group consisting of bis(trihydrocarbylphosphoranylidene)ammonium salt, bis[tris(dihydrocarbylamino)phosphoranylidene]ammonium salt, and tetrakispris(dihydrocarbylamino)phosphoranylideneaminoiphosphonium salt). The reaction between the dihydric phenol and the diepoxide may be conducted in an ether or hydroxy ether solvent at a temperature sufficiently high to produce a poly(hydroxy ether). A particular illustration of such possible approach to forming a reformable resin material having a relatively high glass transition temperature may be gleaned from U.S. Pat. No. 5,401,814; incorporated by reference. One approach envisions a reaction that may include a step of reacting a dihydric phenol or combination of different dihydric phenols with a diepoxide or combination of different diepoxides. The reaction may occur in the presence of a catalyst, (e.g., a catalyst selected from the group consisting of bis(trihydrocarbylphosphoranylidene)ammonium salt, bis[tris(dihydrocarbylamino)phosphoranylidene]ammonium salt, and tetrakis[tris(dihydrocarbylamino)phosphoranlideneamino]phosphonium salt). The reaction between the dihydric phenol and the diepoxide may be conducted in an ether or hydroxy ether solvent at a temperature sufficiently high to produce a poly(hydroxy ether). A particular illustration of such possible approach to forming a reformable resin material having a relatively high glass transition temperature may be gleaned from U.S. Pat. No, 5,401,814; incorporated by reference.
Approaches other than the above to reactions for making materials useful for the present teachings (e.g., a thermoplastic polyether) may include one or more reactions selected from the above first and second approaches, or (a) a reaction product of diglycidyl ether of a biphenol with a dihydroxybiphenyl, in which the repeating unit of the polyhydroxyether contains a hydrocarbon connecting group and a hydrocarbon or halogen substituted phenylene radical, as described in U.S. Pat. No. 4,647,648 (incorporated by reference); (b) a reaction product of a diglydicyl ether of certain amido-dihydric phenols and N-substituted dihydric phenols, as described in U.S. Pat. No. 5,115,075 (incorporated by reference); (c) a reaction product of a dihydric phenol (e.g., a diglycidyl ether of one or more of bisphenol ketone, bisphenol sulfone, resorcinol or hydroquinone) and at least one other dihydric phenol such as 4,4′-ispropylidene bisphenol (bisphenol A), 4,4′-dihydroxydiphestylethylmethane, 3,3′-dihydroxydiphenyldiethylmethane, 3,4′-dihydroxydiphenylmethylpropylmethane, bisphenol, 4,4′-dihydroxydiphenyloxide 4,4′-dihydroxydiphenylcyanomethane, 4,4′-dihydroxybiphenyl, 4,4′-dihydroxybenzophenone, 4,4′-dihydroxydiphenyl sulfide, 4,4-dihydroxydiphenyl sulfone, 2,6-dihydroxynaphthalene, 1,4′-dihydroxynaphthalene catechol, or the like, as described in U.S. Pat. No. 5,164,472 (incorporated by reference); (d) a reaction product (e.g., a reactive extrusion product) of a diglycidyl ether of a dihydric phenol with an amine having only two hydrogens under conditions sufficient to form the polyetheramine, as described in U.S. Pat. No. 5,275,853 (incorporated by reference); (e) a reaction product of dihydric phenol and a diepoxide in the presence of a catalyst selected from bis(trihydrocarbylphosphoranylidene)ammonium salt, bis[tris(dihydrocarbylamino)phosphoranylidene]ammonium salt, or tetrakis[tris(dihydrocarbylamino)phosphoranyliderneamino]phosphonium salt, as described in U.S. Pat. No. 5,401,814 (incorporated by reference); (f) a reaction product prepared by reacting (1) a primary amine or bis(secondary) diamine with (2) a diglycidyl ether and (3) an amine- or epoxy-functionalized poly(alkylene oxide), as described in U.S. Pat. No. 5,464,924 (incorporated by reference); (g) a reaction product of a compound having an average of more than one vicinal epoxide group per molecule and a polyhydric phenol or thiophenol, in the presence of a catalytic amount of a tetranydrocarbyl phosphonium salt in an essentially anhydrous medium, as described in U.S. Pat. No, 4,438,254 (incorporated by reference); (h) a reaction product of a diepoxide (e.g., diglycidyl ethers of dihydric phenols) and a difunctional species selected from dihydric phenols, dicarboxylic acids, bis-secondary amines, primary amines, dithiols, disulfonamides, and compounds that contain two different functionalities capable of reacting with epoxide groups, as described in U.S. Pat. No. 6,011,111 (incorporated by reference); or (i) a hydroxy-phenoxyether reaction product polymer prepared by reacting a difunctional species (that is, a species having two reactive groups), such as a dihydric phenol, with a diepoxide (that is, a compound having two epoxide functionalities) under conditions sufficient to cause the hydroxyl moieties to react with the epoxy moieties to form ether linkages, as described in WO98/14498 (incorporated by reference).
Reformable resin materials according to the present teachings may have a generally linear backbone and may also have at least one ether linkage in repeating units of the generally linear backbone. Materials according to the present teachings may be free of crosslinking, or of any thermoset portion chemically bonded to a generally linear backbone.
It is possible that two or more of the reformable resin compositions described above may be utilized together. For example, two or more reformable resins, each with different glass transition temperatures may be used together for selectively varying properties. This can be achieved by blending the two, or by intermingling preforms of each (e.g., a yarn or weave that has fibers of both higher and lower glass transition).
The teachings herein make advantageous use of reformable resin materials for use in various applications, such as in the construction, appliance, and/or transportation industries. By way of example, reformable resin materials of the teachings find application in transportation vehicle components, such as structural reinforcements, baffle devices, sealing devices, panels (e.g., wall panels, automotive body panels, roof panels, etc.), brackets, beams (e.g., cross-vehicle beams, such as beams useful for supporting instruments of an instrument panel), module frames (e.g., a frame upon which a plurality of components can be mounted, either before, during and/or after assembly of the frame into a vehicle structure).
The resulting articles not only can be made by taking advantage of the beneficial processing characteristics consistent with thermoplastics of the reformable resin materials. But, upon fabrication of the articles, the articles may be further modifiable by forming or otherwise shaping, by heating the article to a temperature above which at least a portion of the reformable resin material that is incorporated into the article is elevated above its Tg. Thereafter, the article can be cooled so the material is below the Tg, thereby causing the material to retain its desired shape. At one or more times when the reformable resin material is above its Tg the reformable resin material is such that it becomes tacky and can form an adhesive bond with an item placed on it. Thus, teachings herein contemplate heating an article having a wall to which a component is to be attached to an elevated temperature above which at least a portion (e.g., below about 60%, about 50%, about 40% about 30%, about 20% or about 10% of the average wall thickness) of the reformable resin material that is incorporated into the wall of the article is elevated above its Tg. At such time when the portion of the reformable resin material is above its Tg, a component is placed in contact with it (optionally in the presence of pressure). Thereafter, the article can be cooled so the material is below the Tg, thereby causing the material to retain its desired shape and secure the component to it by adhesive bonding. It is possible to make use of the Tg and adhesive characteristics of the reformable resins in order to simplify assembly structures by removing the need for certain attachment hardware. This allows for attaching a component directly to the article adhesively, without mechanical fastener hardware or overmolding a structure onto a pultruded beam (the beam may be partially or fully encapsulated by the molded material).
With reference to the material of the polymeric matrix, for any of the embodiments general or specific herein, it may include a thermoplastic polymer (e.g., a thermoplastic epoxy polymer, a reformable resin, a thermoplastic reaction product). The polymer may be a hydroxy-phenoxyether polymer, such as a polyetheramine thermoplastic material. For example, the polymer may be a product (e.g., a thermoplastic condensation reaction product) of a reaction of a mono-functional or di-functional species (i.e., respectively, a species having one or two reactive groups, such as an amide containing species), with an epoxide-containing moiety, such as a diepoxide (i.e., a compound having two epoxide functionalities), reacted under conditions for causing the hydroxyl moieties to react with the epoxy moieties to form a generally linear backbone polymer chain with ether linkages. The polymer may be a reaction product of a diepoxide resin (e.g., BPA), and one or more of a mono primary amine, a di-secondary amine, a dimer captan and/or a di-carboxylic acid.
Though other functional species may be employed, as is taught in U.S. Pat. No. 6,011,111 (incorporated by reference; see, e.g., cols. 6-8) and WO 98/14498 (incorporated by reference; see, e.g., pages 8-11) examples of such mono-functional or di-functional species may include a dihydric phenol, a secondary amine (e.g., a bis-secondary amine), a primary amine, or any combination thereof. Any amine of the functional species can be an aromatic amine, an aliphatic amine or a combination thereof. The mono-functional or di-functional species may have one or two functionalities capable of reacting with epoxide groups to form a generally non-cross-linked polymer. Some particular examples, without limitation, of functional species for reaction with an epoxy moiety in accordance with the present teachings includes an ethanolamine (e.g., monoethanolamine), piperazine or a combination thereof. Any of the illustrative functional species may be substituted or unsubstituted.
Other examples of illustrative materials, functional species and diepoxides are described in U.S. Pat. Nos. 5,115075; 4,438,254; 6,011,111; and WO 98/14498 (see e.g., pages 3-8) along with illustrative synthesis conditions, all incorporated by reference herein (see also U.S. Pat. No. 3,317,471 and 4,647,648, also incorporated by reference herein). Examples of such materials also can be found, without limitation at paragraphs 15-25 of Published U.S. Patent Application No. 20070270515 (Chmielewski et al.), incorporated by reference for all purposes.
The teachings herein also relate to a method for making a composite article. In general, a method in accordance with the present teachings may employ a step of contacting a plurality of segmented forms provided for defining a distributed phase with a generally thermoplastic epoxy reaction product of reactants (e.g., a mono-functional or di-functional species (i.e., respectively, a species having one or two reactive groups, such as an amide containing species), with an epoxide-containing moiety, such as a diepoxide (i.e., a compound having two epoxide functionalities)). That is in a softened state (e.g., in a liquefied molten state). For instance, a method in accordance with the present teachings may employ forming a composite material by passing a mass of fibers and resin through a die (e.g., by extrusion and/or pultrusion), by molding (e.g., injection molding, compression molding, or otherwise), or a combination of each. One or more other methods may be employed to make articles in accordance with the present teachings. For example, it may be possible to make a product by thermoforming.
The contacting may be only after the reaction has completed between the epoxy and the amine (e.g., only after the reaction of epoxy and amine reactants). Thus it is possible that the method herein will involve no chemical reaction between any reactants (e.g., any epoxy and amine reactants) that occurs within a molding, or shaping machine in which the reaction product and the intended distributed phase materials are brought into contact. That is, the method may include advancing a thermoplastic polymer having at least one epoxide functional group reaction product along a rotating feed screw within a barrel of a polymeric material shaping apparatus, and then contacting the thermoplastic polymer with the intended distributed phase material.
It is also possible that a portion of the intended distributed phase material is contacted with reactants prior to any reaction to form the thermoplastic polymer reaction product of the present teachings. For example, it may be possible that the intended distributed phase material is contacted with either or both of an epoxy or amine reactant (e.g., in a liquid state) prior to reaction to form the thermoplastic polymer reaction product. For example, a mass of fibers may be infiltrated with a liquid epoxy reactant, a liquid amine reactant or both. Thereafter, any remaining reactant may be introduced (alone with exposure to any necessary heat and/or pressure) for bringing about a reaction to form the thermoplastic polymer reaction product in situ within the mass of fibers. Use of the reformable resins described herein as pultrusion polymers, when in a fluidic state, are able to provide a surprisingly good infiltration of a mass of fibers for providing an cohesive matrix within which the fibers are distributed.
A method for making an article in accordance with the present teachings may be performed in a continuous manner. For example, fibrous material from a continuous supply (e.g., a reel of the desired fibrous material (e.g., in its desired form, such as a strand, a yarn, a weave, nonwoven mat, or otherwise as described herein) for use as the distributed phase) may be fed continuously to and through a die. The fibrous material may be contacted (e.g., by way of a suitable coating operation, such as roll coating, or otherwise) with the thermoplastic polymer reaction product prior to or at the time when the fibrous material is passed through the die. The fibrous material may be contacted (e.g., by way of a suitable coating operation, such as role coating, or otherwise) with the reactants for the thermoplastic polymer reaction product prior to or at the time when the fibrous material is passed through the die. Upon exiting the die, a composite mass remits. The fibrous material may thus form a distributed phase within the composite mass. The mass may be cut, shaped or otherwise subjected to another (e.g., secondary) operation to render a composite article suitable for use for an intended application.
It may be possible also that a step of co-extrusion may be employed. The step of co-extrusion may include a step of passing a composite mass, such as described above, through a die, while also feeding a supply of base material through the die. The base material may be a polymeric material, a metal material or otherwise. Conditions may be maintained while the materials are passed through the die so that the composite mass becomes bonded to (e.g., mechanically, adhesively, covalently, or any combination thereof), to the resulting shaped base material. For example, it may be possible that the heat from the base material while it is processed through the die, or essentially immediately thereafter, may be sufficiently hot to cause the thermoplastic polymer reaction product to fuse with or otherwise bond to the base material.
As can be appreciated, a variety of suitable composite profiles are possible as a result of the teachings. The profiles may include a longitudinal axis. The composite profiles may be symmetric or asymmetric relative to the longitudinal axis. The composite profiles may include one or more longitudinally oriented ribs. The composite profiles may include one or more transversely extending flanges. The composite profiles may have one or more outer surfaces. The composite profile may have one or more inner surfaces. The composite profiles may include a composite overlay that includes or consists of a composite mass of the present teachings. The composite profiles of the teachings may include a composite overlay that includes or consists of a composite mass of the present teachings. The composite overlay may cover all or part of an outer or inner surface. The composite overlay may include or consist of a composite mass of the present teachings may define all or part of a rib, a flange (e.g., a transversely oriented flange) or both. The composite profiles may include a composite mass that is at least partially or even completely embedded within the base material over some or all of the length of the composite profile. The composite profile may include an extruded profile structure defining a mechanical attachment for securing the profile to another structure (e.g., such as is disclosed in U.S. Pat. No. 7,784,186 (incorporated by reference; see, e.g.,
For use as an extruded carrier for a structural reinforcement and/or baffle (e.g., for a transportation vehicle), there may also be employed an activatable material or at least a portion of an outer surface of the carrier.
The teachings also envision a possible manufacturing system that may be employed for an extrusion operation in accordance with the present teachings. Raw material for forming a base polymeric material body are fed into a hopper associated with an extruder. The extruder may have a die through which the raw material is passed to form a shaped body profile (e.g., an extruded profile). The shaped body profile may be cooled (e.g., by a vacuum cooler) to a desired temperature (e.g., below the softening point of the material, so that it retains its shaped state). A feed system may feed a fibrous material (e.g., by way of rollers) to a suitable device for applying a matrix material for defining a composite fibrous material (e.g., a roll costar). At such device, the material for forming a polymeric matrix is contacted with the fibrous material. A suitable device for defining a shape of the fibrous composite material may be employed, such as a forming roller (or another suitable extrusion and/or pultrusion type shaping device). The forming roller or other suitable device may also serve to help join the fibrous composite material with the shaped base body profile.
Upon joinder the resulting overall composite may be cooled (e.g., by a cooling tank). Optionally, if to be employed for use as a carrier for a baffling and/or structural reinforcement application, the resulting overall composite may be advanced by a conveyor device (e.g., a pulling or pushing device). An activatable material (e.g., a polymeric heat activatable sealant, acoustic foamable material, and/or structural reinforcement material) may be applied to the composite by an extruder (e.g., a cross head extruder). Thereafter, the resulting composite (with or without the activatable material on it) may be cut by a suitable cutting device (e.g., a traveling cut-off saw). By way of illustration, without limitation, the raw material may be a glass filled Nylon® heated to about 260° C. Upon exiting the cooler, the temperature may be about 150 to about 175° C. The fibers may be glass fibers that are roll coated with a reaction product of a monoethanolamine and diglycidyl ether of bisphenol A, while the reaction product in a softened state. Upon exiting the cooling tank the composite may be at a temperature of about 120° C. At the time of passing the extruder, the temperature may be about 90-95° C. The cross-head extruder may extrude one or more masses of a heat activatable epoxy-based structural foam, such as the L-55xx series of materials, available from L&L Products, Inc. See, e.g., U.S. Pat. No. 7,892,396, incorporated by reference for all purposes (an illustrative composition is shown therein at Table I). The heat activatable material may be activatable to expand by foaming, and adhere to an adjoining surface (e.g., a wall defining a part of a vehicle, such as a wall defining a vehicle cavity). The activation may occur upon exposure to the heat of a paint bake oven, following an electrocoating deposition step. The resulting activated material may be expanded to at least about 50%, 100%, 200%, 400%, 600%, or even 1000% of its original volume. The resulting activated material may be expanded from its original volume, but in an amount that is below about 2500%, 2000% or even below about 1500% of its original volume.
The composite material of the present teachings offers the benefit of mechanical properties typically achieved through the use of thermoset polymeric materials (e.g., a thermoset epoxy material) as some or all of a matrix phase of a composite. However, the material has a number of physical attributes that make it suitable for handling and processing, as can be appreciated form the above discussion of processing. The material of the present teachings can also provide post-useful life reclamation, recycling, and/or re-use benefits. The present teachings thus also contemplate methods that include one or more steps of post-useful life reclaiming, recycling, and/or re-using the materials of the present teachings, For example, a step may be employed of separating the polymeric phase (e.g., the polymeric matrix phase) from the distributed phase. A step may be employed of re-using one or more phases of the composite of the present teachings. A step may be employed of recycling one or more phases of the present teachings (e.g., processing at least one of the phases to a different form, size and or shape, from its original form, size and/or shape in the composite material of the present teachings. The material of the present teachings may exhibit a high elongation factor so that it is not brittle yet still very strong. The material may be able to bond to a desired part, substrate, or location. This provides a benefit that assembly operations may be free of welding. The assembly operation may be free of an assembly tolerance stackup. As components may be bonded together (e.g., without mechanical fasteners), the parts may be free of holes, thereby improving precision and eliminating inconsistent punching operations (e.g., with sheet metal). The material may ease geometric dimensioning and tolerances.
The fibrous composite material of the present teachings may be employed in any of a variety of possible forms. It may be employed as an overlay on top of a body (e.g., a shaped polymeric body). It may be employed as an insert (e.g., for forming a continuous adjoining surface with a shaped polymeric body). It may be an encapsulated insert within a shaped polymeric body. It may be employed as a substitute for sheet metal. It may be employed as a substitute for a tube or other generally cylindrical element (e.g., a roll tube or a hydroformed tube). The fibrous composite material may be a patch, a strip, a wrap, or the like that may be used to provide localized reinforcement to another component of an assembly (e.g., a beam that receives some load). The fibrous composite material may be rolled into a tubular shape (e.g., for use as or with cross-car beams, side intrusion or impact beams, or other automotive parts). The fibrous composite material may be thermoformed into a desired shape (e.g., for a roof bow, bumper, or other automotive part). The fibrous composite material may be shaped to provide a structure and support for subcomponents of an assembly. For example, the fibrous composite material may be shaped to form a door inner module, which may provide an internal structure within a vehicle door, which may also provide an area for mounting and/or supporting subcomponents within the door (e.g., a motor for actuating movement of the windows, the locking mechanism, a wire harness, speaker system, ventilation components, mirror controls, demister, and the like).
In one aspect of the present teachings there is contemplated a baffle and/or a structural reinforcement for an article. The baffle and/or structural reinforcement includes a carrier that includes a mass of polymeric material having an outer surface and including a first polymeric material (e.g., a first thermoplastic material). The carrier may be made of a single polymeric material, or a plurality of polymeric materials. The carrier may include a fibrous composite material of the present teachings. That is, the carrier may include a distributed segmented form phase and a polymeric matrix phase. The polymeric matrix of the fibrous composite material may include a generally thermoplastic epoxy reaction product of reactants (e.g., a mono-functional or di-functional species (i.e., respectively, a species having one or two reactive groups, such as an amide containing species), with an epoxide-containing moiety, such as a diepoxide (i.e., a compound having two epoxide functionalities)).
The polymeric material for the matrix of the fibrous composite material of the teachings may be the same as or different from a polymeric body of the carrier, in instances in which the fibrous composite material of the teachings is employed on or within a polymeric body of the carrier.
By way of illustration, the carrier may employ at least one consolidated fibrous insert (which may have a predetermined ordering of fibers within the insert and/or may have a three dimensional shaped configuration) having an outer surface. The at least one consolidated fibrous insert includes at least one elongated fiber arrangement (e.g., having a mass of continuous fibers, which may be in an ordered arrangement, such as by being generally axially aligned relative to each other) distributed in a cohesive mass of a second polymeric material (e.g., a second thermoplastic material). The fibrous insert and associated second polymeric material may adjoin the mass of the first polymeric material in a predetermined location for carrying a predetermined load that is subjected upon the predetermined location. The fibrous insert, the second polymeric material and the mass of first polymeric material include compatible materials, structures or both, for allowing the fibrous insert to be at least partially joined to (e.g., form a single phase with or be miscible in) the mass of the first polymeric material. The structural reinforcement may also include a mass of activatable material selectively applied over at least a portion of one or both of the outer surface of the mass of the polymeric material or the fibrous insert (e.g., on exterior peripheral surface of the carrier, within a cavity of the carrier, or both). The mass of activatable material is capable of activation for expansion by an external stimulus (e.g., heat, moisture, radiation or otherwise) and is capable of curing to form an adhesive bond to at least one surface of the article. Desirably the outer surface of the fibrous insert may be at least partially co-extensive and continuous with the outer surface of the mass of polymeric material.
Materials for a carrier body herein may be a polyamide, a polyolefin (e.g., polyethylene, polypropylene, or otherwise), a polycarbonate, a polyester (e.g., polyethylene terephthalate), an epoxy based material, a thermoplastic polyurethane, a carbon fiber reinforce polymer or any combination thereof. It may be preferred to employ a polyamide (e.g., polyamide 6, polyamide 6,6, polyamide 9, polyamide 10, polyamide 12 or the like). The materials of a carrier body and any overlay and/or insert may be generally compatible with each other in that they are capable of forming a mechanical or other physical interconnection (e.g., a microscopic interconnection) between them, they are capable of forming a chemical bond between them, or both. For example, the first and second materials may be such that they fuse together (e.g., in the absence of any adhesive) when heated above their melting point and/or their softening point. The carriers may also be overmolded with a secondary material, such secondary material may be a polymeric material such as a polyolefin, a polyamide, a polyester, a polyurethane, a polysulfone, or the like, or an expandable polymer (e.g., a structural foam or an acoustic foam).
The polymeric body of any carrier may include a polymeric material that may be filled with chopped fibers (e.g., chopped glass fibers), which may be present in amount of about 25 to about 40 (e.g., about 30 to about 35) weight percent chopped fibers. The average length of such fibers may be below about 20 mm, below about 10 mm or even below about 5 mm. They may be randomly oriented. The first and second materials may be free of any metallic materials.
A fibrous insert and/or a fibrous composite material may include one or more layers (e.g., they may have 2, 3, 4, 6, 15 or more layers) that are consolidated in the sense that they include a plurality of individual fibers that are distributed in a cohesive mass of the second polymeric material. The individual fibers may be distributed in a predetermined ordered arrangement within a matrix of the second polymeric material. Preferably at least a portion of the fibers are ordered in their arrangement (e.g., in a generally ordered relationship relative to each other, such as generally parallel or unidirectional or otherwise generally axially aligned), and thus are not randomly distributed in the second polymeric material. Multiple layers may be consolidated together so that a cohesive mass, including the multiple layers, is formed. The multiple layers may be consolidated so as to form a predetermined shape in the form of a three-dimensional shaped insert. It is also possible that a film or intermediate layer may be located in between one or more of the multiple layers. For instance, the fibrous insert may employ a plurality of layers that include a plurality of elongated fibers (e.g., having a length of at least 1 cm, 3 cm or even 5 cm or longer) that are oriented generally parallel or generally unidirectionally to each other and are distributed in a generally continuous polymeric matrix (e.g., in a continuous matrix of the second polymeric material). The fibers may be mineral fibers (e.g., glass fibers, such as E-glass fibers, S-glass, B-glass or otherwise), polymeric fibers (e.g., an aramid fiber, a cellulose fiber, or otherwise), carbon fibers, metal fibers, natural fibers (e.g., derived from an agricultural source), or otherwise. Desirably the fibers are glass fibers. The plurality of elongated fibers may be oriented generally parallel to each other. They may be braided. They may be twisted. Collections of fibers may be woven and/or nonwoven. The fibers may have an average diameter of about 1 to about 50 microns (e.g., about 5 to about 25 microns). The fibers may have a suitable sizing coating thereon. The fibers may be present in each layer, or in the fibrous insert generally, in an amount of at least about 20%, 30%, 40% or even 50% by weight. The fibers may be present in each layer, or in the fibrous insert generally, in an amount below about 90%, 80%, or even about 70%, by weight. By way of example, the fibers may be present in each layer, or in the fibrous insert, in an amount of about 50% to about 70% by weight. Fiber contents by weight may be determined in accordance with ASTM D2584-11. Tapes and/or sheets for the layers of the fibrous insert may be made by extrusion, pultrusion or otherwise. In this manner, it may be possible to achieve ordering of the fibers in the tapes and/or sheets. The method herein may include a step of impregnating a fibrous mass with the material of the polymeric matrix and passing the resulting impregnated material through a die (e.g., a heated die) so that the fibrous mass is coated with a generally continuous mass of the material of the polymeric matrix. In this manner, it is also possible to achieve desired ordering of fibers relative to each other.
Each layer of the fibrous insert may be in the form of a sheet, a tape or otherwise. Fibers in the sheet and/or tape preferably may have an ordered relationship relative to each other. For example, the fibers may be generally parallel with each other and/or oriented unidirectionally. When consolidating multiple layers of sheet, tape or other form of layer to form a multi-ply fibrous insert, it is preferred that at least one layer of the fibrous insert exhibits an ordered relationship, as opposed to a random relationship, such as is found in fiber mats, which typically employ chopped fibers that are randomly laid across each other.
It is possible that the layers of the fibrous insert are provided as being wound on a reel. Each layer may have a thickness of at least about 0.1 mm or at least about 0.2 mm. Each layer may have a thickness below about 0.5 mm or below about 0.4 mm. For instance, each layer may be about 0.2 to about 0.3 mm in thickness. Some or all of the individual layers may be anisotropic in its mechanical properties, For example, it may exhibit a relatively high flexural modulus and/or strength in a longitudinal direction, but a lower flexure/ modulus and/or strength in a transverse direction, or vice versa.
The fibrous insert may include a plurality of woven strips. For example, it may include a plurality of strips that are cross woven, each strip having a width of at least about 1 mm, at least about 2 mm, or even at least about 3 mm, it may include a plurality of strips that are cross woven, each having a width below about 10 mm, below about 8 mm, or even below about 6 mm. The woven strips may be held together by a polymeric matrix material, e.g., a continuous matrix of the polymeric material of the insert. Thus, the strips are fixed in a predetermined position relative to each other by virtue of the polymeric material. It is preferred that at least some of the strips may each include a plurality of elongated fibers arranged in an ordered relationship relative to each other, desirably within a continuous matrix of polymeric material. However, it is possible that one or more strips may include fibers having a random orientation relationship relative to each other, such as is derived from typical fiber mats. Strips for forming weaves may be made by slitting a tape, sheet or other form to an appropriate width to form strips. Alternatively, it may be possible that the strips are pultruded, extruded or otherwise formed (as described herein) in the desired width.
The material defining the fibrous insert may exhibit a flexural strength per ASTM D790-10 of at least about 450 MPa (e.g., it may range from about 500 to about 1100 MPa). The material of the fibrous insert may exhibit a flexural modulus per ASTM D790-10 of at least about 5 GPa, 10 GPa, 20 GPa, or even at least about 25 GPa (e.g., it may range from about 30 to about 35 GPa).
The fibrous insert may employ a fully densified polymer for the polymeric matrix. The fibrous insert may have a void content that is below about 10% by volume of the insert, and more preferably below about 5% or even below about 2% or 1% as measured by ASTM D2734-09. The fibrous insert may have a density that is below about 40% the density of steel, below about 33% the density of steel, or even below about 25% the density of plain carbon steel.
The fibrous insert may be made to include a plurality of adjoining layers. The adjoining layers may have fiber orientations that are the same or different relative to each other. The fibrous insert may include a woven layer adjoining a non-woven layer. The fibrous insert may include a woven layer adjoining another woven layer. The weave pattern of woven layers within the fibrous insert may be the same or may vary between such woven layers. The width of strips may vary between adjoining layers. The thickness of adjoining layers may be the same or different.
Examples of weave patterns include plain weaves, twill weaves, or otherwise. Overlapping strips may be woven generally orthogonal to one another or at some other angle. The weave may include a plurality of warp and waft strips. The ratio of warp to weft strips may range from about 30:70 to about 70:30. For example it may be about 50:50. It is possible that strips of the warp and weft members may have generally the same width. The warp strip and weft strip widths may vary relative to each other by 10%, 20%, 30% or more. The warp strip and weft strip widths may vary relative to each other by less than about 70%, 60%, 50% or less.
Each adjoining layer of tape and/or sheet in the fibrous inserts herein may be oriented so that it has fibers (i.e., the fibers that are embedded in the polymeric matrix of the tape and/or sheet) aligned in a different predetermined direction relative to fibers of an adjoining layer. Fibers in one layer may be generally at an angle relative to fibers in an adjoining layer (e.g., the axis of fiber orientation as between layers may differ from about 10 to about 90°, such as in the form of an X-ply). For example, one multiple layer structure may include one layer that may have fibers oriented in a first direction of a first plane, and an adjoining layer oriented with its fibers generally in a second plane parallel to the first plane, but at an approximately 90 degree angle.
Desirably each of the adjoining layers are joined together as a cohesive mass. For instance, each of the layers may be bonded together by the polymeric material of the respective layers to form a series of continuous layers. The layers may be bonded together in the absence of any adhesive.
The fibrous composite material, such as in the form of a sheet or a tape (which may serve as a patch or a wrap), may be applied to control failure modes of certain components of an assembly which may be subject to a load, to provide localized reinforcement, or both. For example, a hollow beam (e.g., having a rectangular cross section) receiving a load from the top may have a tendency to shear. Strength may be improved and/or the failure mode may be altered by adding a fibrous composite material as disclosed herein. The fibrous composite material may be attached to the hollow beam to alter its deformation characteristics (e.g., with the composite material being generally planar (or in planar contact with a portion of the beam), acting as a shell around the beam, surrounding the beam as a wrap in a generally helical direction, as a generally cylindrical or tubular structure outside or inside of the hollow beam, or another configuration). For example, a weaved tape may be applied along the side wails of the beam to help resist having a shear plane that arises substantially along the longitudinal axis of the beam (traveling through the middle of the part). The tape (or other form fibrous composite material) may be single ply or multi-ply, with a combination of fiber orientations (e.g., one layer having fibers generally oriented in the longitudinal direction, another layer having fibers in an orientation that is at an angle relative to the longitudinal direction (e.g., at 90 degrees, 45 degrees or otherwise)). The fiber directions may assist in resisting shear or may provide control and/or predictability in failure of the component (e.g., a beam) upon being subjected to a particular load. A secondary component may be applied to further increase strength or alter the failure mode, such as another fibrous layer having a different orientation, or may be a metal, a foam component (inside or outside of the hollow beam, for example), a fibrous mat, or a ductile material (e.g., a rubber-like material). The fibrous insert may have one or more structure/features incorporated therein or attached thereto. For example, one or more fasteners may be employed (e.g., one or more threaded fasteners). One or more lugs may be formed or integrated into the fibrous insert (e.g., for providing a gap for the passage of a coating fluid), One or more rivets (e.g. a self-piercing rivet, a blind rivet or both) may be integrated into the insert. One or more metal blanks may be integrated into the insert, which may be adapted to provide a location on a resulting part for spot welding. One or more studs may be integrated into the insert (e.g., having a base that may have apertures defined therein, which is located within or on a surface of the fibrous insert and which has a post (e.g., a threaded post) that extends outward from the base). One or more metallic panels, sheets, or pieces may be integrated into the insert or secured thereto, such as for providing localized reinforcement.
The one or more structural features may be incorporated into the fibrous insert (or other fibrous composite material) via selective heating. In accordance with the present teachings there is envisioned that one or more assemblies may be made by selectively heating a portion of a structure having a wall (e.g., an outer wall of the fibrous insert) with a thickness to elevate at least a portion of the thickness of the wall to a temperature above the glass transition temperature of a polymer (e.g., a polyamide and/or a reformable resin material as taught herein, which may be reinforced as described herein, such as with a fiber or other phase) that forms the wall. While the at least a portion of the thickness of the wall is above the glass transition temperature of the polymer that forms the wall, an article is contacted with the structure at least partially within the heated region, optionally under pressure. Thereafter, upon heat leaving the heated region, the polymer that forms the wail cools so that resulting polymer in contact with the article is cooled below the Mass transition temperature. An adhesive bond thereby results, with the article remaining attached to the structure by way of the bond. The above method may be employed to form an adhesive bond either with or without an additional applied adhesive. That is, it may be possible that the material of the structure, when heated above its Tg, and then cooled below it, will be capable of forming an adhesive bond directly with the contacted article. Moreover, the tenacity of the bond may be sufficient so as to obviate the need for any fastener for securing the article to the structure. One option for achieving a bonded assembly accordance with the above may be to employ an adhesive layer, wherein the adhesive layer (e.g., having a thickness below about 5 mm, 4 mm, or 3 mm, and above about 0.05, 0.1 or about 0.5 mm) is made of a reformable resin material as described herein.
The structure may be any of a number of suitable forms. For example, it may be an elongated beam. It may have a length and may be solid along all or part of the length. It may have a length and be hollow along all or part of the length. The structure may have a wall thickness, measured from a first exposed surface to a generally opposing exposed surface. The wall thickness may be at least about 0.5 mm, about 1 mm, about 2 mm, about 5 mm, about 10 mm, or about 20 min. The wall thickness may be below about 100 mm, below about 80 mm, below about 60 mm, or below about 40 mm.
The structure may have a predetermined shape. The shape may include one or more elongated portions. The shape may include one or more hollow portions. The shape may include one or more walls that define at least one cavity. The structure may include a plurality of portions each having a different shape. The structure may be configured to define a fascia, which optionally may be supported by an underlying structure. The structure may be configured to define a support that underlies a fascia. The structure may have a panel configuration, e.g., a configuration that resembles a transportation vehicle (e.g., an automotive vehicle) exterior body or interior trim panel.
The structure may be configured to receive and support one or a plurality of articles (e.g., transportation vehicle components), such as for forming a module, By way of illustration the one or more articles may be selected from a bracket, a hinge, a latch, a plate, a hook, a fastener (e.g., a nut, a bolt or otherwise), a motor, a component housing, a wire harness, a drainage tube, a speaker, or otherwise.
Heat may be applied in any suitable way. One approach may be to employ localized heating. For example, it is possible to employ induction heating for selectively heating at least a portion of the above-described structure. To illustrate, it is possible that the structure will be made with a polymer (e.g., a polyamide and/or a reformable resin material as taught herein, which may be reinforced as described herein, such as with a fiber or other phase), and will have a wall thickness. A metallic item (which may be a component desired to be attached to the structure) may be brought into proximity (which may or may not be in contacting relation) with the structure at the desired location of attachment. An induction heating device may be brought into proximity with the metallic item for heating the metallic item, which in turn will heat the structure in the affected location when power is supplied to the induction heating device. Other heating devices may be employed as well for achieving localized heating.
It is possible that time that elapses from the time the structure is initially heated until when an article becomes attached to it by the above steps may be relative short. For example, the operation may take less than about 1 minute, less than about 30 seconds, or less than about 15 seconds. It may take as low as about 1 second, about 3 seconds, or about 5 seconds.
Another approach to forming an assembly in accordance with the present teachings envisions forming a shaped part by heating a of mass material in accordance with the teachings (e.g., a polyamide and/or a reformable resin material as taught herein, which may he reinforced as described herein, such as with a fiber or other phase) to a temperature above the T of the material. When at least a portion of the material is above the Tg, pressure may be applied to the mass of material to define a configured part. For example, it may be thermoformed, molded, or otherwise shaped. The configured part may then be joined with another part to form an assembly. The joinder of parts may be by an adhesive bond, by a mechanical connection (e.g., using a fastener, using a fitted joint configuration, or both), or both. For example, without limitation, at least two generally complementary parts may be secured to each other. If one of the parts is made with a reformable resin material as taught herein, they may be joined together by attaching the parts while at least a portion of that part is above the of the reformable resin material, and then cooling to a temperature below the Tg. Optionally, this approach may be modified to include the employment of a layer of adhesive between the parts, wherein the adhesive layer (e.g., having a thickness below about 5 mm, 4 mm, or 3 mm, and above about 0.05, 0.1 or about 0.5 mm) is made of a reformable resin material as described herein.
The parts may be dissimilar materials. For example, one part may include a reformable resin material of the present teachings. The other part may it a polyurethane, a polyolefin (e.g., a polypropylene), a polyamide, are acrylate, a methacrylate, a polycarbonate, a polyester, or any combination thereof; the other part may include a thermoset material; the other part may be made form a sheet raiding compound or by reaction injection molding.
As indicated the fibrous inserts may have a predetermined shape. The shape may be the result of one or more calculations performed during a step of computer simulation of a crash, a certain stress state or otherwise, and may be selected so as to provide additional localized reinforcement in a predetermined region of the part that will be subjected to a predicted stress condition that is determined from such calculations. The fibrous inserts herein may include one or any combination of a generally sinusoidal geometry over some or all of its length, a pair of spaced apart walls that are joined together by a cross wall, one or more ledges and/or steps, a concave surface portion, a convex surface region, or one or more apertures. As indicated, the fibrous inserts herein may have a three dimensional configuration, in contrast with a generally planar configuration.
The characteristics of the fibrous insert can vary from application to application. One benefit of the present teachings is that the layers of the fibrous insert can be selected to meet the needs of a particular application (e.g., in response to modeling by computer simulation (such as computer crash or stress state simulation)). The insert can be individually built up to include a plurality of layers based upon the performance demanded by the application. Moreover, another benefit of the teachings herein is that localized reinforcement can be achieved by locating the inserts in particular locations that are indicated as requiring additional local reinforcement (e.g., in response to modeling by computer simulation (such as computer crash or stress state simulation)). The teachings herein thus afford the skilled person with a surprisingly expanded ability to selectively tune performance of structural reinforcements. The teachings also contemplate the use of modeling by computer simulation to determine the location at which a carrier is expected to carry a predetermined load in a crash or under a certain stress state. Based upon the results of such modeling, the location at which a fibrous insert should be located can be determined. Also, based upon the results of such modeling, the orientation of fibers and/or the selection of respective adjoining layers of tape or sheet in a fibrous insert can be ascertained. Parts can thereafter be made that are based upon the designs resulting from such modeling. Methods employing such steps are thus within the present teachings as well.
The carriers of the structural reinforcements may be such that the outer surface of the fibrous insert is generally co-extensive with the outer surface of the mass of polymeric material. This may be over some or all of the perimeter of the fibrous insert. It is also envisioned that the fibrous insert may have opposing surfaces that are each exposed and thus visible in the resulting part. For instance, the fibrous insert may have an exposed outer surface and an exposed inner surface. Thus, the fibrous insert may adjoin the mass of polymeric material only along one or more side edges of the fibrous insert. The resulting visible surfaces of the carrier may be substantially free of knit lines or other imperfections that could provide a source of localized weakening of the carrier.
The second polymeric may be applied directly onto the fibrous insert. The second polymeric material may be a liquid poured onto the fibrous insert until the insert is saturated with the second polymeric material. The liquid absorbed by the fibrous insert may account for at least about 30% and less than about 70% of the total weight of the insert after saturation. The saturated insert may polymerize at room temperature or with the addition of heat, such that a rigid solid composite is formed. The resulting composite may then receive the first polymeric material by locating the composite into a tool and molding the first polymeric material (which may be a Nylon material) about the composite.
As appreciated from the above, the carrier may have (i) a polymeric portion defined by the mass of first polymeric material, (ii) a localized reinforcement portion defined by the at least one fibrous insert, and (iii) an interface portion between the polymeric portion and the localized reinforcement portion wherein the polymeric portion, the interface portion and the localized reinforcement portion are a generally continuous structure. The interface portion may include (i) an interpenetrating network defined by the first and second polymeric materials, (ii) chemical bonds between the first and second polymeric materials, or both (i) and (ii).
One or more sides of the activatable material may be tacky. Though it is also possible that one or more sides will be generally tack free to the touch at room temperature. One or more mechanical fasteners may be employed by attaching to or being formed integral with the activatable material, the carrier, or both.
Suitable materials that may be employed for the activatable material include expandable materials and materials that do not expand. However, it is contemplated that the activatable material can be activated to form a foam. For instance, the material may be activated to form a structural foam (e.g., the material may include an epoxy ingredient). The material may be activated to form an acoustic foam. The material may be activated to flow for purposes of sealing a region within a cavity. The material may include a combination of a material that is activatable to expand and a material that is not activatable to expand.
The structural reinforcement of the present teachings may be employed for structurally reinforcing an article, such as by locating the structural reinforcement within a cavity of the article and activating the activatable material so that it expands and bonds to a surface of the article. The structural reinforcement may also be employed to seal and/or baffle the cavity. In a preferred application, the structural reinforcement is employed to reinforce a transportation vehicle such as an automotive vehicle.
By way of example, the structural reinforcement may be positioned within a cavity of a transportation vehicle (e.g., an automotive vehicle) prior to coating the vehicle. The activatable material may be activated when subjected to heat during paint shop baking operations. In applications where the activatable material is a heat activated, thermally expanding material, an important consideration involved with the selection and formulation of the material comprising the activatable material is the temperature at which a material reaction or expansion, and possibly curing, will take place. For instance, in most applications, it is undesirable for the material to be reactive at room temperature or otherwise at the ambient temperature in a production line environment. More typically, the activatable material becomes reactive at higher processing temperatures, such as those encountered in an automobile assembly plant, when the material is processed along with the automobile components at elevated temperatures or at higher applied energy levels, e.g., during paint or e-coat curing or baking steps. While temperatures encountered in an automobile assembly operation may be in the range of about 140° C. to about 220° C., (e.g., about 148.89° C., to about 204.44° C. (about 300° F. to 400° F.)), body and paint shop applications are commonly about 93.33″ C. (about 200° F.) or slightly higher. Following activation of the activatable material, the material will typically cure. Thus, it may be possible that the activatable material may be heated, it may then expand, and may thereafter cure to form a resulting foamed material.
As indicated, the teachings herein also relate to a method for making a carrier for an activatable material (e.g., for structural reinforcement for an article). The method may include a step of inserting at least one fibrous insert (which may be consolidated at the time of the step of inserting) having an outer surface and including at least one elongated fiber arrangement into a cavity of a tool. A mass of polymeric material may be molded in contact with the fibrous insert so that a resulting molded mass of polymeric material integrally adjoins the fibrous insert (which is consolidated in its final state) and the outer surface of the fibrous insert is at least partially co-extensive and continuous with the outer surface of the resulting molded mass of polymeric material. A mass of activatable material may be applied (e.g., overmolded, mechanically attached or otherwise) selectively over at least a portion of one or both of the outer surface of the resulting mass of the polymeric material or the fibrous insert. Consistent with the teachings above, the mass of activatable material may be capable of activation for expansion by an external stimulus (e.g., to at least partially, if not completely, fill a gap or a cavity) and may be capable of curing to form an adhesive bond to at least one surface of the article to which it is attached.
The method may include a step of at least partially shaping the fibrous insert after it is placed in the cavity of the tool. For example, the tool may be preheated to a temperature above the softening temperature and/or the melting temperature of a polymer of the at least one fibrous insert prior to placing the fibrous insert in the cavity of the tool. The method may include a step of at least partially shaping the fibrous insert after it is placed in the cavity of the tool and while molding the mass of polymeric material. For instance, heat and/or pressure that results from introducing the mass of polymeric material into the cavity (e.g., by injection molding), may at least partially cause the fibrous insert to assume a shape dictated by one or more of the walls defining the cavity. Thus it is possible that the fibrous insert is not preformed prior to placement in the cavity, and it assumes its final shape only while in the cavity. Of course, it is also possible that the fibrous insert is preformed prior to placement in the cavity.
The fibrous insert, prior to the inserting step, may be provided in the form of one or more layers of a tape and/or sheet, in which the fibers may be fixed in position relative to each other (e.g., as a result of consolidation, by which a cohesive mass of the fibers distributed in a continuous polymeric matrix is formed). The method may thus include a step of fabricating the fibrous insert to include a plurality of layers of tape and/or sheet. For example, the method includes a step of consolidating a plurality of layers of tape and/or sheet while the plurality of layers is subjected to heat and optionally an elevated pressure. For instance, a temperature may be employed that is above the melting and/or softening point of the polymer of the tape and/or sheet to cause two or more adjoining layers to fuse and remain joined together upon cooling. A pressure of about 0.1 to about 1 MPa may be applied (e.g., about 0.2 to about 0.6 MPa). The temperature and pressure may be employed for a desired amount of time to achieve essentially complete densification. It will be appreciated that the teachings afford for the formation of various consolidated insert structures.
The fibrous insert may be thermoformed to form a predetermined shape. The fibrous insert may be thermoformed during a step of consolidating. A resulting thermoformed fibrous insert may thereafter be placed in a tool cavity and molten thermoplastic polymeric material may be introduced in contact with it.
The step of molding may include a step of introducing molten polymeric material into the tool cavity by way of a gate that is positioned in generally opposing relationship with the at least one fibrous insert. In this manner, upon introduction into the cavity, the molten polymer contacts the fibrous insert before it contacts a wall defining the cavity.
Carriers made in accordance with the present teachings may have a wall having a first surface and a generally opposing second surface. The wall may have a thickness ranging from about 0.2 to about 6 mm (e.g., about 1.5 to about 4 mm). At select regions within a carrier, it is possible that at least about 20%, 40%, 60%, 80% or even 100% of the wall thickness is defined by the fibrous insert or overlay. The fibrous insert or overlay may have a contoured outer surface portion that is visibly exposed on the carrier. The fibrous insert or overlay may have a generally flat outer surface portion that is visibly exposed on the carrier. The first surface and the second surface may be generally parallel to each other.
The fibrous insert or overlay may occupy at least about 10%, 20%, 30% or even 40% by weight of the overall carrier. The fibrous insert or overlay may be less than about 90%, 80%, or even 70% by weight of the overall carrier.
Thus it is possible that at least a portion of the first surface and the second surface are each visibly exposed and will be composed of the fibrous insert or overlay. The carriers may have one or more additional structural reinforcements or other structural features, such as one or more ribs, bosses or otherwise. These features may be free of or they may include a fibrous insert in accordance with the present teachings.
It is contemplated that the materials as disclosed herein may be paintable. Paintability may be desirable, for example, if any surface is visibly exposed. The material may be ink jet printed. The material may be painted with conventional e-coat systems. The material may be paintable, as it may have an affinity for taking paint. This may be due, at least in part, to the polarity of the material and/or the hydroxyl functionality of the backbone (e.g., generally linear backbone polymer chain).
Parts herein may be employed for any of a number of purposes. For example, they may be employed to structurally reinforce a transportation vehicle such as an automotive vehicle. In this regard, a part may be placed in a cavity of a vehicle body structure, such as a vehicle frame. After applying an e-coat layer to the vehicle body (e.g., within the cavity), the part may be subjected to heat from a bake oven, which causes the activatable material to activate (e.g., expand and fill the cavity), and become bonded to the vehicle body.
The manufacturing system may also include one or more pultrusion steps. By way of example, a possible manufacturing system may be employed for a pultrusion operation instead of or in addition to an extrusion operation in accordance with the present teachings. Raw material for forming a base polymeric material body may be fed into a receptacle associated with a pultruder. The pultruder may have a die through which the raw material is passed to form a shaped body profile (e.g., a pultruded profile). A mass of fibers may be pulled through the die and infiltrated while in the die with the raw material. The raw material (which may be a one-component or a plural-component mixture of reactive ingredients) may have a relatively low viscosity sufficient to the raw material to impregnate the mass of fibers and thereafter harden in a desired shaped profile that includes the mass of fibers. The shaped body profile may be cooled (e.g., by a vacuum cooler) to a desired temperature. A feed system may feed a fibrous material (e.g., by way of rollers) to the die at which the raw material for forming a polymeric matrix is contacted with the fibrous material (e.g., the mass of fibers). In an instance, where the pultruded material has thermoplastic characteristics (e.g., a thermoplastic epoxy) a forming miller (or another suitable extrusion type shaping device) may then further define the desired shape of the resulting fibrous composite material. The forming roller may also serve to help join the fibrous composite material with any optional shaped base body profile. Upon any joinder the resulting overall composite may be cooled (e.g., by a cooling tank). Optionally, if to be employed for use as a carrier for a baffling and/or structural reinforcement application, the resulting overall composite may be advanced by a conveyor device (e.g. a pulling or pushing device). An activatable material may be applied to the composite by an extruder (e.g., a cross head extruder). Thereafter, the resulting composite (with or without the activatable material on it) may be cut by a suitable cutting device (e.g., a traveling cut-off saw). By way of illustration, without limitation, the raw material may be a glass filled Nylon® heated to about 260° C. Upon exiting the cooler, the temperature may be about 150 to about 175° C. The fibers may be glass fibers that are roll coated with a reaction product of a monoethanolamine and diglycidyl ether of bisphenol A, while the reaction product in a softened state. Upon exiting the cooling tank the composite may be at a temperature of about 120° C. At the time of passing the extruder, the temperature may be about 90-95° C. The cross-head extruder may extrude one or more masses of a heat activatable epoxy based structural foam, such as a structural reinforcement material in the L-55xx series, available from L&L Products, Inc.
The teachings herein can make any number of different parts. One example is a door intrusion beam that can be installed in an automotive vehicle for helping resist deformation that would intrude into a vehicle body in the event of a collision. The intrusion beam may be extruded. However, desirably it is pultruded and has a pultrudate with a profile that may be constant or varying along its length.
The teachings herein provide for a pultruded structure comprising an elongated tubular pultrudate structure (e.g., a composite having a polymeric matrix) having a first end and a second end. At least one attachment device may be adapted for attaching the tubular structure to a door frame (e.g., a vehicle door frame). The elongated tubular structure may have a longitudinal axis and also has at least one reinforcement portion that includes a continuous fiber reinforcement embedded in a polymeric matrix and has a plurality of fibers aligned generally parallel with the longitudinal axis. A plurality of fibers (e.g., at least about 50%, 60%, 70% or more by weight of the total fiber content) may extend from the first end to the second end; by way of example the plurality of fibers may be generally aligned with the longitudinal axis. The plurality of fibers may be embedded in the polymeric matrix under a state of tension or compression.
The structure may be open or closed along its length. The at least one attachment device may include an adhesive, a mechanical fastener, or both for attaching to the door frame. The elongated tubular structure may include one or more strips of an activatable polymeric material on an outer surface, the activatable material adapted for damping of vibration, for resisting flutter, or for bonding to an adjoining structure, such as that disclosed in U.S. Patent Publication No. 2002/0024233, incorporated by reference herein for all purposes.
The continuous fibers may be preloaded in the at least one reinforcement portion. The elongated tubular structure may have a constant profile along the longitudinal axis. From about 40% to about 80%, about 50% to about 70%, by weight of the beam is fibers. The fibers may be glass fibers. The polymer of the polymeric matrix may be an epoxy. The teachings herein further provide for a method of making a vehicle structure including an elongated tubular structure that is pultruded.
Turning now to a discussion in more detail of forming profiled products using a thermoplastic epoxy in accordance with the general teachings of that material herein, there is envisioned a method of combining reactants and contacting the combined reactants and/or reaction product of the reactants with a mass of fibers. The contacting may be during a step of pultruding and/or extruding a profile. Discussed previously above was a method for extruding an article using a thermoplastic epoxy wherein the thermoplastic epoxy is formed into pellets and fed into an extrusion hopper. Another approach envisions pultruding a thermoplastic epoxy material, which may or may not include a mass of fibers.
Accordingly, the teachings herein also envision a method of making a thermoplastic pultruded article, comprising the steps of pulling a plurality of continuous fibers through a die for defining a continuous profile that has at least two portions that are not coplanar and have differing thickness relative to each other; contacting the plurality of continuous fibers with one or more reactants for forming a polymer for a generally continuous polymeric matrix of the a resulting pultruded article, and applying a sufficient amount of energy to cause a continuous primary reaction of the two or more reactants to continuously forma thermoplastic, pultruded article having a thermoplastic polymeric matrix in contact with the continuous fibers and embedding the continuous fibers therein.
Though described in connection with a thermoplastic epoxy, the teachings herein are more general and may apply to pultruding other materials as well such as thermoset materials. Examples of other materials may include polyesters, polyurethanes, epoxies, or otherwise. The die may be about 0.2 to about 1 (e.g., 0.5) meters in length. The rate of the pultruding is at least about 0.5 (1, 2 or 3) meters per minute. The die may include an opening therein into which the reactants are introduced so that the step of contacting occurs within the die. The contacting may occur in advance of the die (e.g., in a bath or pool).
The method may also include a step converting the thermoplastic pultruded article to a thermoset pultruded article by employing a secondary reaction that occurs under an energy condition that is different from the energy condition for the primary reaction sufficient for causing crosslinking of at least a portion of the polymeric matrix.
In general, it may also be possible to employ one or more reactants that permit an optional delayed cross-linking, reaction to occur. For example, one or more of the reactants may include one or more moieties that are capable of reacting (e.g., in the presence of a certain stimulus, such as further heating and/or some other form of a predetermined electromagnetic radiation (e.g., infrared, ultraviolet, microwave or otherwise) for achieving cross-linking of a molecule with in itself and/or with an adjoining molecule. Desirably such radiation affords cross-linking while maintaining a resulting article made by additive manufacturing to remain below its Tg. Thus, it may be possible that crosslinking may be realized within and/or between adjoining layers. Thus, the teachings contemplate an optional step of causing at least a portion of an article made with the teachings to include cross-linking, such as by causing a cross-linking reaction to occur (e.g., by subjecting feed material and/or the resulting article to electromagnetic radiation as described).
The epoxide and the second reactant may be present in approximately equal molar stoichiometric proportions. The cross section may be changed along the length of the resulting article.
The method may include a step of subjecting the resulting article to a secondary shaping operation, selected from thermoforming, blow molding, hydroforming, insert injection molding, compression molding, cutting, heat shaping, joining (e.g., by adhesion, compression fitting or the like). The secondary operation may be performed continuously.
The method may further comprise pulling the resulting thermoplastic pultruded article over a heated mandrel for imparting a curvature or other variable shape over at least a portion of the pultruded article. The resulting article may have an ultimate tensile strength (UTS) of at least 300 MPa to less than 1000 MPa. The resulting article may have a tensile modulus of
The resulting article may be a structure for use as a reinforcement within a vehicle cavity. The article may be a structure or cross beam. The impact direction of the beam may be transverse to fiber orientation. The beam may include fibers having an axis oriented transversely to axis of expected impact.
Shaped articles in accordance with the teachings herein generally (e.g., whether by pultrusion, extrusion or otherwise) may be subjected to one or more secondary operations (e.g., cutting, thermoforming, overmolding, machining). The secondary operation may be performed in an in-line process which may be as part of the same in-line process as the pultrusion or extrusion process. A manufacturing system may be included in-line with the pultrusion system which may allow for expedited manufacturing of parts (e.g., those shown at
Such shaped articles may include composite articles. As a result, the methods purposed herein include a method of making a composite article comprising the steps of pultruding a first polymeric composite structure having a plurality of first fibers embedded in a first polymeric matrix, fabricating a second polymeric composite structure having a plurality of second fibers embedded in a second polymeric matrix, and securing the second polymeric composite structure with the first polymeric composite structure to define a composite article that includes each of the first polymeric composite structure and the second polymeric composite structure.
The first polymeric composite structure may include a plurality of continuous glass fibers embedded in a polymeric matrix in a concentration of from about 40% to about 80% or even from about 50% to about 70%, by weight of the first polymeric composite structure. The first polymeric composite structure may include a plurality of continuous fibers embedded in a polymeric matrix wherein the polymeric matrix includes an epoxy. The first polymeric composite structure may include a plurality of continuous fibers embedded in a polymeric matrix wherein the polymeric matrix includes a thermoplastic epoxy.
The second polymeric composite structure may include a plurality of glass fibers embedded in a polymeric matrix in a concentration of from about 20% to about 80%, or even from about 40% to about 60% by weight of the second polymeric composite structure. The second polymeric composite structure may include a plurality of fibers embedded in a polymeric matrix wherein the polymeric matrix includes an epoxy, a Nylon, a polyester (e.g., polybutylene terephthalate (PBT), or combinations thereof. The second polymeric composite structure may include a plurality of fibers embedded in a polymeric matrix wherein the polymeric matrix includes a thermoplastic epoxy. The step of fabricating the second polymeric composite structure may include a step of extruding the second polymeric composite, injection molding the second polymeric, composite, pultruding the second polymeric composite, thermoforming the second polymeric composite, compression molding the second polymeric composite, or any combination thereof.
The step of securing the first polymeric composite and the second polymeric composite may include a step of adhering the first polymeric composite with the second polymeric composite, mechanically connecting the first polymeric composite with the second polymeric composite, a step of welding the first polymeric composite with the second polymeric composite, or a combination thereof. The step of securing the first polymeric composite and the second polymeric composite may include a step of inserting a coupling device between the first polymeric composite and the second polymeric composite, and a step of adhering the first polymeric composite with the second polymeric composite via the coupling, mechanically connecting the first polymeric composite with the second polymeric composite via the coupling, welding the first polymeric composite with the second polymeric composite via the coupling, or any combination thereof. The shape of the first polymeric composite and the second polymeric composite may be complementary so that they are in generally mating relationship with each other. The first polymeric composite and the second polymeric composite may be similarly sized and/or shaped. The first polymeric composite and the second polymeric composite are of different size and/or shape. One or more of the first polymeric composite and the second polymeric composite may comprise fibers arranged in a mat.
It will be appreciated that, even though the embodiments of
The teachings herein are illustrated in connection with a carrier for a structural reinforcement, in which the carrier is generally elongated (e.g., it may be at least about 25 mm long, at least about 50 mm long or even at least about 100 mm long). However, the teachings are not intended to be so limiting. The teachings also contemplate their usage for forming carriers for baffling and/or sealing. The carriers may thus have lengths that are shorter than about 25 mm (e.g.. about 15 mm or shorter). The carriers may be longer than they are wide. The carriers may be wider than they are long.
As can be appreciated from the teachings herein, various benefits and/or advantages may be realized. For example, parts may be prepared that have a carrier that is made of a material free of a thermosetting plastic. Parts may be prepared that have at least a portion of the activatable material located over and in contact with a fibrous insert of the present teachings.
As used herein, unless otherwise stated, the teachings envision that any member of a genus (list) may be excluded from the genus; and/or any member of a Markush grouping may be excluded from the grouping.
Unless otherwise stated, any numerical values recited herein include all values from the lower value to the upper value in increments of one unit provided that there is a separation of at least 2 units between any lower value and any higher value. As an example, if it is stated that the amount of a component, a property, or a value of a process variable such as, for example, temperature, pressure, time and the like is, for example, from 1 to 90, preferably from 20 to 80, more preferably from 30 to 70, it is intended that intermediate range values such as (for example, 15 to 85, 22 to 68, 43 to 51, 30 to 32 etc.) are within the teachings of this specification. Likewise, individual intermediate values are also within the present teachings. For values which are less than one, one unit is considered to be 0.0001, 0.001, 0.01, or 0.1 as appropriate. These are only examples of what is specifically intended and all possible combinations of numerical values between the lowest value and the highest value enumerated are to be considered to be expressly stated in this application in a similar manner. As can be seen, the teaching of amounts expressed as “parts by weight” herein also contemplates the same ranges expressed in terms of percent by weight. Thus, an expression in the of a range in terms of “at least ‘x’ parts by weight of the resulting composition” also contemplates a teaching of ranges of same recited amount of “x” percent by weight of the resulting composition.”
Unless otherwise stated, all ranges include both endpoints and all numbers between the endpoints. The use of “about” or “approximately” in connection with a range applies to both ends of the range. Thus, “about 20 to 30” is intended to cover “about 20 to about 30”, inclusive of at least the specified endpoints.
The disclosures of all articles and references, including patent applications and publications, are incorporated by reference for all purposes. The term “consisting essentially of to describe a combination shall include the elements, ingredients, components or steps identified, and such other elements ingredients, components or steps that do not materially affect the basic and novel characteristics of the combination. The use of the terms “comprising” or “including” to describe combinations of elements, ingredients, components or steps herein also contemplates embodiments that consist of, or consist essentially of the elements, ingredients, components or steps.
Plural elements, ingredients, components or steps can be provided by a single integrated element, ingredient, component or step. Alternatively, a single integrated element, ingredient, component or step might be divided into separate plural elements, ingredients, components or steps. The disclosure of “a” or “one” to describe an element, ingredient, component or step is not intended to foreclose additional elements, ingredients, components or steps.
It is understood that the above description is intended to be illustrative and not restrictive. Many embodiments as we as many applications besides the examples provided will be apparent to those of skill in the art upon reading the above description. The scope of the invention should, therefore, be determined not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications are incorporated by reference for all purposes. The omission in the following claims of any aspect of subject matter that is disclosed herein is not a disclaimer of such subject matter, nor should it be regarded that the inventors did not consider such subject matter to be part of the disclosed inventive subject mater.
Claims
1. A pultruded structure comprising:
- an elongated tubular structure having a first end and a second end;
- at least one attachment device adapted for attaching the tubular structure to a vehicle;
- one or more strips of an activatable polymeric material on an outer surface, the activatable material adapted for damping of vibration, for resisting flutter, or for bonding to an adjoining structure;
- wherein the elongated tubular structure has a longitudinal axis and also has at least one reinforcement portion that includes a continuous glass fiber reinforcement embedded in a polyurethane matrix and has a plurality of glass fibers aligned generally parallel with the longitudinal axis.
2-5. (canceled)
6. The structure of claim 1, wherein the continuous glass fibers are preloaded in the at least one reinforcement portion.
7. The structure of claim 1, wherein the elongated tubular structure has a constant profile along the longitudinal axis.
8. The structure of claim 1, wherein from about 40 to about 80% by weight of the beam is fibers.
9-11. (canceled)
12. A method of making the structure of claim 1, wherein the elongated tubular structure is pultruded.
13. A method of making a composite article, comprising the steps of:
- i. pultruding a first polymeric composite structure having a plurality of glass fibers embedded in a polyurethane matrix;
- ii. fabricating a second polymeric composite structure having a plurality of fibers embedded in a polymeric matrix; and
- iii. securing the second polymeric composite structure with the first polymeric composite structure to define a composite article that includes each of the first polymeric composite structure and the second polymeric composite structure.
14. The method of claim 13, wherein the first polymeric composite structure includes a plurality of continuous glass fibers embedded in a polymeric matrix in a concentration of about 40% to about 80% by weight of the polyurethane composite structure.
15-16. (canceled)
17. The method of claim 13, wherein the second polymeric composite structure includes a plurality of glass fibers embedded in a polymeric matrix in a concentration of about 20% to about 80% by weight of the second polymeric composite structure.
18. The method of claim 13, wherein the second polymeric composite structure includes a plurality of fibers embedded in a polymeric matrix and wherein the polymeric matrix includes an epoxy, Nylon, a polyester, a polyether, or combinations thereof.
19. (canceled)
20. The method of claim 13, wherein the step of fabricating the second polymeric composite structure includes a step of extruding the second polymeric composite, injection molding the second polymeric composite, pultruding the second polymeric composite, thermoforming the second polymeric composite, compression molding the second polymeric composite, or any combination thereof.
21. The method of claim 13, wherein the step of securing the first polymeric composite and the second polymeric composite includes a step of adhering the first polymeric composite with the second polymeric composite, mechanically connecting the first polymeric composite with the second polymeric composite, a step of welding the first polymeric composite with the second polymeric composite or a combination thereof.
22. The method of claim 20, wherein the step of securing the first polymeric composite and the second polymeric composite includes a step of inserting a coupling device between the first polymeric composite and the second polymeric composite, and a step of adhering the first polymeric composite with the second polymeric composite via the coupling, mechanically connecting the first polymeric composite with the second polymeric composite via the coupling, welding the first polymeric composite with the second polymeric composite via the coupling, or any combination thereof.
23. The method of claim 13, wherein the shape of the first polymeric composite and the shape of the second polymeric composite are complementary so that they are in generally mating relationship with each other.
24. The method of claim 21, wherein the first polymeric composite and the second polymeric composite are similarly sized and/or shaped.
25. The method of claim 21, wherein the first polymeric composite and the second polymeric composite are differently sized and/or shaped.
26. The method of claim 13, wherein one or more of the first polymeric composite and the second polymeric composite comprise fibers formed in a mat.
27. A method of making a pultruded article, comprising the steps of:
- a) pulling a plurality of continuous fibers through a die for defining a continuous profile that has at least two portions that are not coplanar and have differing thickness relative to each other;
- b) contacting the plurality of continuous fibers with one or more polymeric materials;
- c) applying a sufficient amount of energy to form a pultruded article having a polyurethane-based polymeric matrix in contact with the continuous fibers and embedding the continuous fibers therein.
28. The method of claim 27, wherein the die is about 0.2 to about 1 meters in length.
29. The method of claim 28, wherein the rate of the pultruding is at least about 0.5 meters per minute.
30. The method of claim 28, wherein the die includes an opening therein into which the polymeric materials are introduced so that the step of contacting occurs within the die.
31-74. (canceled)
Type: Application
Filed: Mar 10, 2016
Publication Date: Feb 8, 2018
Inventors: Craig Chmielewski (Shelby Township, MI), Henry E. Richardson (Washington, MI), Jeffrey T. Shantz (Metamora, MI), Nick Holstine (Royal Oak, MI), Milko Dimovski (Clinton Township, MI), Alex Mangiapane (Macomb Township, MI), Liwen Li (Troy, MI), Joseph Thomas (Lapeer, MI)
Application Number: 15/555,999
