Abstract: The invention concerns a process for preparation of light weight objects comprising calendering, extrusion, blow or injection moulding a resin of polypropylene, polystyrene, HD polyethylene or copolymers thereof and, admixed therein, thermally expandable microspheres including a thermoplastic polymer shell encapsulating a propellant, at a temperature sufficient to result in expansion of the microspheres, wherein said polymer shell is made of a homo- or co-polymer from ethylenically unsaturated monomers comprising more than 80 wt % of nitrile containing monomers. The invention further concerns light weight objects obtainable by the process.

Abstract: The invention provides systems, methods, and articles useful in the production of foams, and, in particular microcellular foams. The systems include a restriction element that reduces the backflow of polymer melt in an extruder while polymeric material is injected into a mold or ejected from a die. The restriction element is positioned upstream of a blowing agent injection port to maintain the solution of polymer and blowing agent in the extruder above a minimum pressure throughout an injection or ejection cycle, and preferably above the critical pressure required for the maintenance of a single-phase solution of polymer and blowing agent. The systems can be used in injection molding, blow molding, or in any other processing techniques that include injection or ejection cycles. In some embodiments, the systems utilize reciprocating screws for injection or ejection.

Abstract: The cabinetry of the present invention facilitates lower manufacturing costs, lighter products that are easier to maneuver and less costly to transport, and simpler product assembly by reducing the number parts to be assembled, while maintaining the structural integrity of the cabinetry. The PTV cabinetry of the present invention utilizes molded plastic foam parts formed from expanded polystyrene or phenolic foam. The foam parts are preferably functionally designed to replace the equivalent parts presently being made by wood fabrication or other molded plastic techniques. In a preferred embodiment, a PTV cabinet may be assembled from thee matching molded foam parts. The foam parts in accordance with the present invention may be uniquely located with respect to one another via locating features molded into the foam parts. Once assembled, an external cabinet or cosmetic fascia part may be placed over the foam parts.

Abstract: CO2 is used as the blowing agent, and a first and second control agents are injected into the melt, the first control agent being designed to dissolve and cool the melt and consisting of ethanol, while the second control agent is only designed to cool the melt and consists of H2O2, the injected amount of ethanol being just sufficient for achieving the highest possible dissolution of CO2 in the melt and the injected amount of H2O2 being such that the foaming produced by ethanol is minimized. The apparatus includes arrangements for conditioning and feeding the blowing agent and control agents into the melt. The blocks and boards exhibit dimensional stability and good self-extinction features.

Abstract: The invention provides micro- and nano-porous materials made from crosslinked polymers crystallized from supercritical fluids. The resulting products show an open cell porous network, and can be used for a variety of applications in medical fields, textiles, separation science and others. The invention also provides methods for obtaining such products.

Abstract: A novel class of transparent polymeric foams from high Tg polymers comprising submicron cells and a process for their production is described. The polymers are preferably high glass transition materials and the process comprises saturating a consolidated polymer shape with an inert gas at a temperature above the glass transition temperature of the polymer and under a pressure of at least 9000 psi for a period adequate to dissolve the gas in the polymer shape and then controllably cooling the polymer shape to produce the submicron cell structure.

Abstract: A novel class of transparent polymeric foams comprising submicron cells and a process for their production is described. The polymers are preferably high glass transition materials and the process comprises saturating a consolidated polymer shape with an inert gas at a temperature above the glass transition temperature of the polymer and under a pressure of at least 9000 psi for a period adequate to dissolve the gas in the polymer shape and then controllably cooling the polymer shape to produce the submicron cell structure.

Abstract: Disclosed herein is a production apparatus of expansion-molded articles, comprising a mold equipped with a foamed particle feeder having a foamed-particle feed opening and a compressed-air ejection nozzle opening toward the mold, by which foamed particles contained in a hopper is filled into the mold through the foamed-particle feed opening by ejecting compressed air from the compressed-air ejection nozzle and then heated to expand them, and the foamed particles thus expanded are then cooled, thereby producing an expansion-molded article, wherein the apparatus is equipped with a compressed-air discharge orifice opening toward the foamed particle filling side of the apparatus in the course of a foamed-particle supply line connecting the hopper to the foamed-particle feed opening. An auxiliary member for transfer of foamed particles used in the production apparatus, and a production method of expansion-molded articles using this apparatus are also disclosed.

Abstract: The present invention is a process for producing a thermoplastic foam sheet comprising contacting a molten monovinylidene aromatic or olefinic polymer with a physical blowing agent to form a polymer/blowing agent mixture, and foaming the mixture into a region of lower pressure within a sheet extrusion line, wherein the extrudate is pulled and compressed to form a thermoplastic foam sheet having a uniform thickness.

Abstract: A module for a modular conveyor belt, is described. The module is of a micocellular polymeric foam produced by an injection molding process. The foam polymeric material exhibits excellent mechanical properties required for modular conveyor belts capable of withstanding long service lives. Also, the reduced weight in comparison to conventionally molded modules helps decrease wear on the conveyor belt support structures including the drive sprockets.

Abstract: A thermoplastic polyester resin is fed into a twin extruder, wherein a resin is heated for melting, thereby removing moisture in the resin by evacuating and sucking from a vent port thereof, injecting a foaming agent into the resin to which is pushed out as a foaming sheet and, after that, forming the foaming sheet which is divided into a forming body and a trimming loss, whereby the trimming loss is crushed to obtain crushed materials which are provided so as to put the materials into the twin extruder as collection materials and recycle them.

Abstract: In the extrusion of feed-stuff pellets and relevant consumer products, the extruded products are subject to expansion as a result of the boiling of their water content when the products, after being exposed to high extrusion pressure and a correspondingly high temperature, are discharged to the atmosphere through the extrusion nozzles. Such an expansion is directly aimed at, but it is desirable to be able to control it, which is difficult by adjustment of the ordinary process parameters. With the invention it has been found that the expansion which arises can be controlled in a highly constant manner, i.e. by carrying out the extrusion into a closed chamber in which an over-pressure of a few bar is established in relation to the atmospheric pressure, and which can be regulated. The extrusion products can be continuously discharged from this chamber, or they can be discharged intermittently in portions.

Abstract: A rubber glove is produced by sequentially performing the step of immersing a glove mold in a coagulating synthetic rubber latex containing synthetic rubber in latex form, thermally expansible microcapsules, and a rubber coagulant to form a coagulant-containing synthetic rubber film on the surface of the glove mold; the step of immersing the glove mold in rubber-incorporating latex to form a gelled rubber layer; the step of heating a rubber laminate composed of the synthetic rubber film and the gelled rubber layer to vulcanize the rubber laminate; and the step of turning the vulcanized rubber laminate inside out, and removing it from the glove mold. This method produces a rubber glove, which is excellent in anti-blocking properties and grip under dry or wet conditions, by a simple procedure and for a low cost.

Abstract: A method for manufacturing products with a blown foamy structure, starting from a mass comprising at least natural polymers such as starch and fibers, in particular natural fibers, wherein the mass (M, S) is passed under pressure into or through a mould (23, 63) and the mass (M, S) is heated in the mould (23, 63) in a manner such as to give rise to gelatinization and cross-linking of the natural polymers, with the fibers extending through the product, while the mass prior to the introduction into the mould has temperature which is below the gelatinization temperature and in the mould is brought at least to the baking temperature.

Abstract: A coating composition for fabrics includes wetted microspheres containing a phase change material dispersed throughout a polymer binder, a surfactant, a dispersant, an antifoam agent and a thickener. Preferred phase change materials include paraffinic hydrocarbons. The microspheres may be microencapsulated. To prepare the coating composition, microspheres containing phase change material are wetted and dispersed in a dispersion in a water solution containing a surfactant, a dispersant, an antifoam agent and a polymer mixture. The coating is then applied to a fabric. In an alternative embodiment, an extensible fabric is coated with an extensible binder containing microencapsulated phase change material to form an extensible, coated fabric. The coated fabric is optionally flocked. The coated fabrics are manufactured using transfer techniques.

Abstract: Microcellular rigid foams with a matrix consisting of cross-linked duromers, especially of polytriazine resins, and with an apparent density of 20 to 95 percent of the density of the compact matrix material. The rigid foams are highly stable and highly temperature resistant and are suitable for use, e.g., as material for aircraft lining.

Abstract: A heat-resistant polymer foam is disclosed which has excellent heat resistance, a fine cellular structure, and a low apparent density. The heat-resistant polymer foam comprises a heat-resistant polymer having a glass transition point of 120° C. or higher, e.g., a polyimide or polyether imide, and has an average cell diameter of from 0.01 &mgr;m to less than 10 &mgr;m. This heat-resistant polymer foam can be produced by, for example, impregnating a heat-resistant polymer under pressure with an non-reactive gas such as carbon dioxide, which is in, e.g., a supercritical state, reducing the pressure, and then heating the polymer at a temperature exceeding 120° C. to foam the polymer.

Abstract: A process prepares expandable propylene polymer beads by mixing propylene polymer melt with a volatile organic blowing agent and with a nucleating agent in an extruder, whereupon the extrusion and pelletization of the extrudate takes place in a water bath under conditions of temperature and pressure at which practically no foaming of the pellets takes place.

Abstract: A thermosetting foam, preferably a polyurethane foam is prepare by mixing all the components in one or more extruders and directing the chemical streams to a mixing head where the catalyst is added. Thus, the reaction can be controlled in a facile manner, whereby clogging of the extrusion head is avoided.

Abstract: A process is described for the production of mouldings based on biological material, wherein potato skins, optionally in the presence of a plasticiser such as glycerol or urea and lecithin and of a water-resistant biodegradable polymer such as polylactic acid, is subjected to a thermomechanical treatrment such as extrusion and then shaped. The mouldings have good mechanical properties and a good biodegradability.

Abstract: A fibrillated foamed article and process for producing the same is described. The fibrillated articles are useful as tape backings, filters, thermal and acoustical insulation and as a diffuse reflector for use in optical applications such as computer displays and as reinforcement fibers for polymers or cast building materials such as concrete.

Abstract: Process for the preparation of expanded polyvinylarene particles in which polyvinylarene particles pre-expanded to an apparent density do ranging between 600 and 200 kg/m3 are impregnated by an inorganic gas, and the impregnated particles thus obtained are expanded to an apparent density of at least three times lower than do.

Abstract: A high performance structural foam is used for stiffening parts such as plastic parts. The foam could be formulated for in-mold use at elevated temperatures or at ambient temperatures for use with previously molded parts. Various ingredients are used to control the properties of the foam.

Abstract: A foam extrusion assembly having a melt region which receives and melts a plurality of material pellets, an agent addition assembly which adds a foaming agent to the melted material pellets, and a mixing assembly which substantially mixes the melted material pellets and the foaming agent with one another. The mixing assembly includes a generally elongate barrel through which the melted material pellets and the foaming agent are urged generally from an inlet to an outlet of the barrel.

Abstract: A method for making a resilient material includes providing a particulate polymer, discrete pieces of foam, a foaming agent and a plasticizer. The polymer, foam pieces and plasticizer are mixed and disposed in a mold. The mold is heated to cause melting of the polymer without melting of the foam. After coating of the melted polymer, a heterogeneous resilient cushion is formed with gelated polymer surrounding the discrete foam pieces.

Abstract: A process for the production of expanded polyester, in particular PET, is performed by extrusion of polyester starting material have an intrinsic vircosity of at least 0.8 dl/g and an added expanded agent. To this end a twin screw extruder (14) is utilized provided with two interpenetrating screws (26) having a ratio between their axial separation and diameter lying between 0.6 and 0.8 and co-rotating at a speed of between 15 and 40 rpm. Preferably the ratio between the axial separation and diameter of the screws (26) lies between 0.69 and 0.78 and the ratio between the length and diameter of the screws (26) lies between 20 and 26.

Abstract: Traveling molds are used in conjunction with an extruder to form foamed products from starch and/or starch/polymer blends.

Abstract: A method for extruding foam of a thermoplastic elastomer, which is a blend of olefin rubber and polyolefin resin, includes the steps of mixing the thermoplastic with water, introducing the mix to an extruder, melting and compressing the thermoplastic elastomer and water and extruding the resultant mix as foam. In more detail, a first quantity of thermoplastic elastomer in pellet form is mixed with a second quantity of water. The mixed water and thermoplastic elastomer is introduced to an extruder. The thermoplastic elastomer is allowed to soak for a predetermined period of time after mixing. The thermoplastic elastomer is melted and mixed with the water to a uniform mix of thermoplastic elastomer and water. The mix is extruded through a die, wherein the water expands in a vapor form to create foam cells with the cells having walls of the thermoplastic elastomer.

Abstract: The present invention provides a process for producing a foamed resin article, the process comprising: a step (the first step) of impregnating any one crystalline thermoplastic resin or resin composition containing, as an elementary ingredient, a crystalline thermoplastic resin selected from a certain group, under an elevated pressure which is not lower than the critical pressure of a substance with which the selected crystalline thermoplastic resin or resin composition is to be impregnated, with a fluid of the substance, and a step (the second step) of releasing the resin or resin composition impregnated with the substance from the foregoing pressurized condition in a period of less than 10 seconds.

Abstract: Stable foam caulk, sealant and insulation compositions are disclosed. The compositions comprise solid, waxy non-ionic lipophilic surfactants having low HLB values. These surfactants, upon foamed dispensing of the composition, provide stable support for bubbles formed from drying of a latex emulsion of a film forming polymer and a volatile liquid hydrocarbon propellant. In addition to use in caulking, sealant or insulation methods, the composition can be used to form artificial terrains and other hardenable structural surfaces as backgrounds or support means for hobbies, crafts, and the like.

Abstract: An improved coat hanger extrusion die wherein the aperture of the die land widens along the extrusion axis of said die to the die exit opening, thereby forming an expansion zone, and a method for extruding foamed polypropylene sheet having an improved surface appearance.

Abstract: A foaming and forming method for soft and hard types poly products that includes blending soft or hard type poly material (expanding resin) with selected proportion of additives of carbonic calcium powder, 2-heptanone, soda powder, water, starch power and phosphoric acid-3 to form an evenly blended product solution, injecting the blended product solution into a silicon or steel mold for rapidly generating required air bubbles (beehive shapes) to expand the product solution a number of times, hardening the product solution to form a semi-finished product to be released from the mold immediately, and performing colored painting and embellishment for the semi-finished product to form a light weight and easy to transport poly product.

Abstract: Process for production of three-dimensional objects by stereolithography in which a laser hardens particular areas of constantly succeeding layers of resin fluid. Prior to or during laser light action, the particles, which define physical or mechanical qualities of the object-to-be-produced, will be added into, and/or alternatively, will be produced within the resin fluid, leading to a resin-fluid-particle-mixture. The particles are integrated into the resin and/or compound with resin and/or other particles by means of laser light action or ultrasonic mixing.

Abstract: Azeotropic compositions made up of (a) from about 26 to about 72% by weight perfluorohexane and (b) one compound selected from (1) about 36 to about 74% by weight 2-methyl butane or (2) about 28 to about 53% by weight n-pentane in which the sum of the weight percent (a) and weight percent (b) is 100 percent may be used as blowing agents in the production of polyurethane/polyurea foams.

Abstract: An acoustical insulation foam having, either with or without elastification, an Asker C hardness of less than about 65, a density of about 5 to about 150 kg/m3, a cell size of about 0.05 to about 15 mm, an open cell content of 0 to about 100 volume percent, a thickness of about 1 to about 200 mm, and a width of about 100 to about 3000 mm; comprising; (A) one or more alkenyl aromatic polymers, (B) one or more substantially random interpolymers and (C) optionally, one or more nucleating agents and (D) optionally, one or more other additives; and (E) one or more blowing agents.

Abstract: Azeotropic compositions made up of (a) from about 4 to about 50% by weight 1,3-dioxolane and (b) one compound selected from (1) about 75 to about 96% by weight cyclopentane, (2) about 60 to about 79% by weight 2-methyl pentane, (3) about 59 to about 77% by weight 3-methyl pentane, and (4) about 50 to about 69% by weight n-hexane in which the sum of the weight percent of (a) plus weight percent of (b) is approximately 100 percent are used as blowing agents in the production of polyurethane/polyurea foams.

Abstract: Low-density, high service temperature polymer foam is extruded by heating a crystalline polymer resin above its crystalline melt point to melt the resin, selecting a blowing agent combination, combining the blowing agent combination with the resin to create a mixture, cooling the mixture to a temperature approaching a freezing temperature for the mixture, and extruding the foam through a die. The blowing agent combination is made up of 50 to less than 100 mole percent of a first blowing agent having a boiling temperature at STP of greater than 310° K, and more than 0 to 50 mole percent of a second blowing agent having a boiling temperature at STP of less than 310° K. The blowing agent combination has an equilibrium solubility vapor pressure in the polymer of less than 45 atm at the foaming temperature and greater than or equal to 1 atm at the glass transition temperature.

Abstract: This invention provides a method for stably adding a predetermined amount of supercritical carbon dioxide at a fixed delivery rate into a forming machine and also a process for producing an expanded thermoplastic resin product by making use of the addition method. Carbon dioxide is charged from a liquefied carbon dioxide cylinder (1) into a predetermined amount deliverable pump (2) while allowing the carbon dioxide to remain in a liquefied state. When the carbon dioxide is pressurized and delivered by the predetermined amount deliverable pump (2), a delivery pressure of the carbon dioxide is controlled at an optional pressure within a range of from a critical pressure (7.4 MPa) of carbon dioxide to 40 MPa to deliver the carbon dioxide without any fluctuation of the amount of the delivery by setting up the pressure of a pressure control valve (3). The carbon dioxide is heated to a critical temperature (31° C.) of carbon dioxide or higher to convert it into supercritical carbon dioxide.

Abstract: The invention provides systems, methods, and articles useful in the production of foams, and, in particular microcellular foams. The systems include a restriction element that reduces the backflow of polymer melt in an extruder while polymeric material is injected into a mold or ejected from a die. The restriction element is positioned upstream of a blowing agent injection port to maintain the solution of polymer and blowing agent in the extruder above a minimum pressure throughout an injection or ejection cycle, and preferably above the critical pressure required for the maintenance of a single-phase solution of polymer and blowing agent. The systems can be used in injection molding, blow molding, or in any other processing techniques that include injection or ejection cycles. In some embodiments, the systems utilize reciprocating screws for injection or ejection.

Abstract: A method for producing a foamed granulate, wherein a thermoplastic synthetic material is placed in an extruder, the synthetic material is melted, a pressurized expanding agent is fed through one or several injection nozzles, the molten material enriched with the expanding medium is foamed as it exits through a perforated plate arranged at the outlet of the extruder and is granulated by a cutting device arranged behind the perforated plate. Also disclosed is a device for implementing the method and the foamed granulate.

Abstract: An extrusion foaming method for obtaining a styrene resin foam by introducing a blowing agent into the resin under pressure by which a foam having excellent heat insulating property and compressive strength can be produced with excellent stability using a blowing agent which is as environmentally safe as possible, characterized in that a foam is obtained by using a blowing agent comprising mainly less than 40% by weight and 5% by weight or more of an ether, and more than 60% by weight and not more than 95% by weight of a saturated hydrocarbon having 3 to 5 carbon atoms, based on the entire amount of the blowing agent, or as required, by using a blowing agent wherein a part of the saturated hydrocarbon in the foregoing blowing agent is replaced by a fluorinated hydrocarbon with concern for the environment, and preferably in that the ratio Z/X of cells constituting the foam wherein X is the average cell size in the direction of extrusion and Z is the average cell size in the direction of thickness is adjusted t

Abstract: A blowing agent composition includes a blowing agent consisting of liquified carbon dioxide and 1,1-difluoroethane, or a mixture consisting of liquid carbon dioxide and at least one other liquid or pressure-liquified component selected from the group consisting of ethers with a total of 2 to 4 carbon atoms; ketones with 3 to 5 carbon atoms; alcohols with 1 to 5 carbon atoms; aliphatic hydrocarbons selected from the group consisting of propane, butane, pentane, hexane, heptane; cyclic hydrocarbons with 3 to 12 carbon atoms; fluorohydrocarbons selected from the group consisting of trifluoromethane, 1,1,1-trifluoroethane, 1,1,2-trifluoroethane, 1,1,2,2-tetrafluoroethane, 1,1,1,2-tetrafluoroethane, 1,1,1,3,3-pentafluoropropane and 1,1,1,3,3-pentafluorobutane; phosphate esters and phosphonate esters containing three C1-C4-alkyl groups optionally substituted by one or more halogen atoms. The composition comprises 5 to 50% by weight of liquid carbon dioxide.

Abstract: Method and composition for making an expanded polyethylene material by forming a foamable melt of polyethylene, a nucleating agent, a material which retards migration of alkanes, and a blowing agent which comprises 10 to 100 mole percent ethane. In one disclosed embodiment, the melt is passed through an annular extrusion die to form an elongated tube of extruded material which is then expanded, slit lengthwise and laid flat to form a sheet of the expanded material.

Abstract: The present invention provides a process for producing uncrosslinked polypropylene-based resin foam sheets which is characterized by using an extrusion foaming apparatus having a gear pump which is interposed between the extruder and the die and which is linked by means of adapters, wherein the pressure (Pg) at the inlet of the gear pump is within the range specified by the following formula (Formula 1) and the extruder is controlled so that the value of Pg is constant. Formula 1 Pc≦Pg(atm)≦Pc+90 Pc=(&khgr;−1)/H &khgr;: theoretical expansion ratio when the foaming agent added is 100% held H: coefficient of solubility of the foaming gas in the resin at the resin temperature in the gear pump inlet (cm3(STP)/cm3·atm) and the like.

Abstract: A thermally conductive, pitch based foam composite having a particulate content. The particulate alters the mechanical characteristics of the foam without severely degrading the foam thermal conductivity. The composite is formed by mixing the particulate with pitch prior to foaming.

Abstract: Process for preparing a flexible polyurethane foam by reacting a polyisocyanate and two different polyols under foam forming conditions so as to prepare a rigid foam and by crushing the rigid foam so obtained in a direction perpendicular to the direction of rise of the foam. Flexible foams are obtained which do not show a major glass transition temperature between −100° C. and +25° C. and which have an anisotropy of 1.80 to 4.00.

Abstract: The cylinder head (8) of an injection molding machine has a transverse bore (20), in which is threadedly engaged a gas introduction device (21) connected to a gas bottle (22), having a pressure regulator (23). The device has a body (24) which carries a valve poppet (25) in a complementarily shaped bore (26) opening to the passage through the cylinder head. A spring (27) normally closes the poppet valve. A control valve (28), under control of the system (7) is provided upstream of the poppet valve. Gas is introduced into the injection chamber of the machine after suck back and before screw rotate for feeding plastics material to the injection chamber. On injection, the material is injected with the gas added to it.

Abstract: Stable foam caulk, sealant and insulation compositions are disclosed. The compositions comprise solid, waxy non-ionic lipophilic surfactants having low HLB values. These surfactants, upon foamed dispensing of the composition, provide stable support for bubbles formed from drying of a latex emulsion of a film forming polymer and a volatile liquid hydrocarbon propellant. In addition to use in caulking, sealant or insulation methods, the composition can be used to form artificial terrains and other hardenable structural surfaces as backgrounds or support means for hobbies, crafts, and the like.

Abstract: A method for manufacturing a plastic object may include the steps of: (a) providing an injection moulding device with a mould that includes two mould parts which in a closed position define a mould cavity; (b) providing foaming means for causing foaming in the mould cavity of plastic injected into the mould cavity; (c) providing blocking means for temporarily rendering the foaming means effectively inactive; (d) energizing the blocking means; (e) choosing as plastic a mixture of two plastics, wherein the first plastic is a non-type A plastic and the second plastic is a type A plastic that constitutes a maximum of roughly 30 percent by mass of the mixture, wherein the type A plastic is a plastic with high melt strength compatible with the first plastic, for instance HMS PP which is high-melt-strength polypropylene; (f) causing a formed object to cool to a chosen temperature, opening the mould cavity and removing the cooled object.

Abstract: A supermicrocellular foamed material and a method for producing such material, the material to be foamed such as a polymerplastic material, having a supercritical fluid, such as carbon dioxide in its supercritical state, introduced into the material to form a foamed fluid/material system having a plurality of cells distributed substantially throughout the material. Cell densities lying in a range from about 109 to about 1015 per cubic centimeter of the material can be achieved with the average cell sizes being at least less than 2.0 microns and preferably in a range from about 0.1 micron to about 1.0 micron.