Abstract: A thin wall PTFE tube is formed from an extruded green tube. The PTFE tube includes an inner tubular surface and an opposed outer tubular surface defining a tubular wall of a first thickness. The tubular wall is compressed to uniformly reduce the wall-thickness and circumferentially orient the tube. The PTFE tube is positioned over a first elongate roller with the inner tubular surface being in contact therewith. A second roller is positioned against the outer tubular surface of the PTFE tube. The pair of rollers are counter rotated so as to circumferentially compress the tubular wall between the rollers. This results in the uniform reduction in the tubular wall from the first thickness to a lesser second thickness and a circumferential orientation otherwise not occurring in an extruded PTFE paste extrusion.

Abstract: An intravascular catheter including a reinforcement layer having a plurality of interwoven metal wire members and polymer members. The polymer members are thermally processed to permeate the metal wire members to form a polymeric layer having an orientation which is interwoven with the metal wire members.

Abstract: A sintered ferrite body is obtained by baking a raw ferrite material including about 0.1% to about 30% by weight of a glass having, as a single material, and having a specific resistance &rgr; (&OHgr;) of about 10 or more in the log &rgr; unit, and a softening point of about 400° C. to about 700° C., in order to overcome the problem that relatively low specific resistance of a ferrite material causes insulation deterioration as well as migration of an internal electrode in a laminated ferrite component when constructing the laminated ferrite component from a sintered ferrite body.

Abstract: A decurl apparatus includes a heating device to heat an image recording carrier web at a constant temperature, which exceeds the glass transition temperature of a support for a constant time period; and a cooling device for subsequent cooling of the image recording carrier web to a temperature equal to or lower than the glass transition temperature, while the image recording carrier web maintains a predetermined shape. The heating device includes an induction-heated heating roller and holding rollers arranged at arbitrary angular positions with respect to the outer circumference of the heating roller. As a result, the image recording carrier web is reliably decurled by a simple construction without being influenced by a transfer velocity or the like.

Abstract: A mat of polymeric fibers is treated to alter a filtration surface by the application of heat and pressure. The filtration surface is heated to a temperature sufficient to soften the fibers and pressure is applied to compact the softened fibers in order to reduce the average pore size on or at the filtration surface.

Abstract: The invention relates to methods of forming shaped articles from suspensions which include ceramic or metallic powder, or from solutions or suspensions which include one or more pharmaceutical substances or other components. The method comprises the steps of: (a) combining solvent, polymer, cross-linking agent precursor and optional further components and placing into a mould of desired shape; (b) increasing temperature of mould contents to activate cross-linking agent; (c) allowing mould contents to solidify to sufficient extent to remove mould; (d) removing shaped article from the mould.

Abstract: The present invention involves a method of processing polyacrylonitrile into a predetermined form. The first step in this method includes preparing a solution of a room temperature solvent that will dissolve polyacrylonitrile at room temperature and, a room temperature non-solvent that will not dissolve polyacrylonitrile at room temperature. The solution is prepared with sufficient non-solvent to render the room temperature solvent inoperable such that it will not dissolve polyacrylonitrile at room temperature and such that it will be operable at temperatures above 65° C. to dissolve polyacrylonitrile therein. The second step in the present invention method involves combining polyacrylonitrile with the solution to form a mixture, in an amount of at least 20%, by weight, of polyacrylonitrile, based on the total weight of the mixture. Preferred is about 20% to about 50% by weight of the polyacrylonitrile.

Abstract: A method of producing a polyphosphate, orthophosphate, phosphonate or the like chemical treatment cake is disclosed. Conventional commercially available treatment material is obtained in powder form and mixed with water to initiate an exothermic reaction. The material is then poured into a mold and placed inside an insulated hermetic cabinet and allowed to quiescently cool in the passive environment of the cabinet. The cake is harder, more uniform and relatively free of inclusions compared to cakes formed by other methods.

Abstract: A process for modifying a uniformity of a tire comprising a radial carcass ply of rubberized organic fiber cords is modifications of radial force variation (RFV) and conicity force (COF), which is carried out by dividing RFV- or COF-rejected tire into two portions and applying different thermal hysteresis to these portions under specified conditions.

Abstract: The present invention provides a method for heat treating a polymer PTC composition to increase the peak resistivity of the composition making it especially well suited for high voltage applications. A polymer PTC composition having a melting point temperature Tmp is provided. The temperature of the polymer PTC composition is increased at a rate, r1, to a temperature greater than Tmp. The temperature of polymer PTC composition is held at the temperature greater than Tmp for a predetermined period of time. Then the temperature of the polymer PTC composition is decreased to a temperature less than Tmp at a rate, r2, wherein r2 is greater than r1.

Abstract: A method of treating a flexible multi-layer member exhibiting a glass transition temperature and including a surface layer, the method composed of: moving the member through a member path including: a contact zone defined by contact of the member with an arcuate surface including a curved contact zone region; a pre-contact member path before the contact zone; and a post-contact member path after the contact zone; heating sequentially each portion of the surface layer such that each of the heated surface layer portions has a temperature above the glass transition temperature while in the curved contact zone region; and cooling sequentially each of the heated surface layer portions while in the contact zone such that the temperature of each of the heated surface layer portions falls to below the glass transition temperature prior to each of the heated surface layer portions exiting the curved contact zone region, thereby defining a cooling region, wherein the heating is accomplished in a heating region encompas

Abstract: The invention is an elongate intracorporeal member having a polymer jacket secured to a high strength shaft with the polymer jacket having an outer layer of polymeric material and an inner layer formed of polymeric adhesive. In one embodiment, a balloon catheter has a proximal high strength tubular section with a polymer jacket having an polymeric outer layer and an adhesive polymer inner layer. In another embodiment, a guidewire has an elongate core with polymer jacket disposed about at least a portion of the elongate core, wherein the polymer jacket comprises a polymeric outer layer an inner layer of polymeric adhesive disposed between and bonding the outer layer to the elongate core.

Abstract: The invention comprises a process for making a membrane electrode assembly comprising a polymer electrolyte membrane having two opposite faces, on each face of which is applied a catalyst layer and a gas distribution layer. The two gas distribution layers in the membrane electrode assembly are formed by hydrophobized carbon substrates which, using appropriate inks containing at least one catalyst, dissolved ionomer and solvent, are each coated with a catalyst layer and are then laid on opposite faces of the polymer electrolyte membrane with the catalyst layers still in the moist state. Afterwards, a firm bond between electrolyte membrane, catalyst layers and carbon substrates is produced by treating the membrane electrode assembly at elevated temperature under pressure.

Abstract: We have determined that strength characteristics of elastic strand improve when the strand is heated. Thus, the present invention is directed to improving strength characteristics of an elastic strand by heating the strand. The strand may be heated by thermal conduction and/or convection, by irradiative methods using, for example, infrared or microwave radiation, or some combination of these. If the elastic strand is made at a location different from the location where the strand is used as a raw material, the strand may be heated at either location, or both locations. Furthermore, the strand may be heated in-line, i.e. as part of the process that makes the strand or the process that uses the strand as a raw material, or off-line, i.e. in a step separate from either of the aforementioned processes. Finally, in addition to heat treating the strand, the strand's exposure to water or water vapor may be regulated to reduce or eliminate strength degradation.

Abstract: A forming track forms flexible plastic tubing which carries fuel from a fuel tank to an engine into a desired shape. The forming track includes a curved channel to receive a round tubing and a pair of opposing flanges to secure the tubing in the forming track. The tubing slightly deforms between the pair of opposing flanges as the plastic tubing is positioned in the channel. After the tubing is inserted, the opposing flanges secure the tubing in the forming track. While positioned in the forming track, the tubing is set by heating and rapid cooling, thermosetting the tube into the shape of the forming track.

Abstract: This invention relates to processes for the assembly of three-dimensional structures having periodicities on the scale of optical wavelengths, and at both smaller and larger dimensions, as well as compositions and applications therefore. Invention embodiments involve the self assembly of three-dimensionally periodic arrays of spherical particles, the processing of these arrays so that both infiltration and extraction processes can occur, one or more infiltration steps for these periodic arrays, and, in some instances, extraction steps. The product articles are three-dimensionally periodic on a scale where conventional processing methods cannot be used.

Abstract: The present invention involves a carbon fiber-filled sheet molding compound and method of manufacturing the same. The invention comprises providing chopped automotive carbon fibers, a predetermined resin paste, a first carrier film, and a second carrier film. The method further involves coating substantially completely one side of one of the first and second carrier films with the predetermined resin paste to define a coated side, depositing the chopped automotive carbon fibers onto the coated side, and covering the deposited carbon fibers with the second carrier film to define a compactible carbon-filled laminate. The method further includes compacting the carbon-filled laminate to admix the resin paste with the carbon fibers between the films, whereby to form the automotive carbon fiber-filled sheet molding compound.

Abstract: Treatment for the dimensional stabilization of containers in PET or COPET obtained by injection-blow molding consisting in subjecting to beat treatment during the blowing phase, preforms obtained from PET or COPET upgraded in the solid state in the presence of small quantities (0.01-0.2% by weight) of a dianhydride of an aromatic tettacarboxylic acid, preferably pyromellitic dianhydride.

Abstract: A method of charging fibrous webs with nonaqueous polar liquids. A web 20 that contains nonconductive fibers is wetted with a nonaqueous polar liquid 14. The web 20 is then substantially dried 22 to provide a fibrous electret web. The fibrous electret web can be used as a filter in a filtration face mask 40 that is adapted to cover the nose and mouth of the wearer. The present method has the advantage over known charging methods in that the nonaqueous liquid requires less energy for drying than is required for aqueous liquids. Additionally, many filter webs can be directly wetted with nonaqueous liquids, which cannot be easily wetted with aqueous liquids.

Abstract: Textile materials having high colorfastness, and methods for their production are described. The process involves heatsetting a textile material, then applying a polysiloxane/catalyst combination to the heatset material. The textile material is then dried at low temperature, thereby resulting in a material having good colorfastness and shade. The process can be used to process fibers, yarns or fabrics, and is particularly useful in the processing of microdenier fibers.

Abstract: A process and a device for shaping and processing pipes. The device contains a carriage assembly and a plurality of bending units. The process includes the steps of moving a plurality of bending units freely along the pipes and performing a plurality of simultaneous bending operations using the adjustable bending units on the pipes. This process can also include the steps of engaging two end sections of the pipes using one of the plurality of bending units and applying at least one additional bending unit to the pipe corresponding to a number of further bending operations planned. With the device, there can also be a plurality of tracks to guide the carriage assembly. In addition the bending units can also comprise robots for shaping the pipes. These pipes can be heated before, during or after they are bent.

Abstract: A method for preheating a permeable, thermoformable material having first and second sides includes supplying heated fluid to a fluid distribution system; regulating flow of the fluid such that fluid having a first temperature flows at a first velocity, and fluid having a second temperature less than the first temperature flows at a second velocity greater than the first velocity; introducing the fluid onto the first side of the material; and developing a suction on the second side of the material sufficient to draw the fluid through the material thereby convectively heating the material; wherein the flow of the fluid is regulated so as to transfer substantially uniform energy flux to the material.

Abstract: To provide a method for producing a molded crystalline resin article which enables a higher crystallization degree and to mass-produce the molded crystalline resin articles. The method comprises molding a molded resin article from a thermoplastic resin containing a crystalline resin followed by performing a heating process to obtain a molded crystalline resin article having a surface layer whose crystallization index is 0.9 or higher when determined by IR spectrometry. It is preferable that the temperature of the heating process is within the range of 20° C. lower than the crystallization temperature of the molded resin article to 30° C. higher than the crystalline temperature, and that the crystalline resin is a polypropylene resin.

Abstract: A method of forming a carpeted plastic part includes positioning a carpet between first and second mold halves, wherein the carpet has a back surface. A non-reinforced plastic strip is positioned adjacent a portion of the back surface of the carpet. A hollow parison of reinforced plastic material is formed between the first and second mold halves. The first and second mold halves are then closed together to form a carpeted plastic part having a thinned-down region of the reinforced plastic material adjacent the plastic strip such that the plastic strip is sandwiched between the thinned-down region and the carpet to form a flexible living hinge.

Abstract: Disclosed is a method for the preparation of a high-quality sintered body of a rare earth oxide or a composite oxide of a rare earth oxide and an adjuvant oxide such as aluminum oxide. The method comprises shaping a rare earth oxide powder characterized by specified particle diameter distribution values of D50 and D90 and a specified specific surface area or a powder blend of the rare earth oxide and adjuvant oxide into a powder compact and subjecting the powder compact to a sintering heat treatment at a specified sintering temperature by increasing and decreasing the temperature up to and from the sintering temperature each at a rate not exceeding a specified upper limit.

Abstract: A rubber for a hot press cushioning pad having a value of loss tangent (tan &dgr;) in accordance with dynamic viscoelasticity measurement of at most 0.04, wherein the temperature condition is set at a hot press temperature ranging from 150° C. to 300° C., and the frequency condition is set to a time period of one press cycle ranging from 1 to 2×104 seconds.

Abstract: An improved method of producing a fluid filled elastomeric bladder for occupant weight sensing involves annealing the bladder material prior to its installation in a vehicle seat so as to quickly relieve initial stress due to stretching of the bladder material which occurs during fluid injection. In a preferred implementation, the initial stress is relieved by immersing the fluid-filled bladders in heated water for a time period on the order of 60 seconds or more. Alternatively, the bladder material may be heated with steam or radiant heat, by injecting heated fluid into the bladder, or by injecting heated air into an empty bladder before fluid injection. In each case the initial stress is quickly relieved, substantially eliminating a potential source of error in the sensed weight.

Abstract: A process for increasing the flame resistance of polyethylene-containing, single- or multilayer hollowware, in particular plastic fuel tanks, by heat treating the hollowware at 60-135° C.

Abstract: An exterior automotive quality paint coat is laminated to the surface of a plastic car body member of panel. A dry paint transfer film is first laminated to a relatively thin semi-rigid thermoformable resinous backing sheet. The backing sheet side of the resulting laminate is then laminated to a relatively thick thermoformable substrate sheet comprising the same or a compatible polymeric material. The two sheets are joined by extruding the thick substrate sheet and using the heat of extrusion to then laminate the thin backing sheet to the thicker extruded substrate sheet. The resulting thick sheet laminate is then thermoformed, preferably by first heating the laminate to a forming temperature, followed by vacuum forming the laminate to a three-dimensional shape of the finished automotive part, such as a facia, ready to put on a vehicle.

Abstract: A method is provided for fabricating an implantable prosthesis for repairing a defect in a muscle and tissue wall, the prosthesis having a first surface which is convex and a second surface which is concave. The method includes steps of providing a first template having a predetermined concave shape; providing a second template having a predetermined convex shape; placing a piece of implantable flexible mesh between the first and second templates; heating the mesh to a predetermined temperature for a predetermined length of time so that the mesh retains the predetermined shape; and removing the mesh from between the first and second templates. In another aspect, a package is provided for storing a resilient, preformed implantable prosthesis having a first surface with a concave shape and a second surface with a convex shape.

Abstract: A method of producing reformed crosslinked polymer articles provides reformed crosslinked articles free of visible and objectionable folds, seams and interfaces on reformed surfaces thereof. In a preferred embodiment, a product is produced by a method including the steps of extruding a silane-grafted polyethylene tube, heating an end of the tube, reforming the end of the tube to produce a radially enlarged sealing surface thereon, cooling the reformed tube, and curing the reformed tube to produce an increase in the degree of crosslinking of the polyethylene material.

Abstract: A method for improving elastic modulus of a biodegradable resin composition in a simple and rapid manner was disclosed. According to such method, a molded product made of poly-lactic acid is subjected to an aging at a temperature higher by 15° C. or more than the glass transition point of such poly-lactic acid and under a humidified atmosphere with a relative humidity (RH) of 60% or above. This successfully raises the elastic modulus from 107 Pa to 109 Pa within a short time. Such improvement in the elastic modulus allows production of a molded product not causative of deformation in an aging test typically conducted at 80° C. and 80% RH for 100 hours.

Abstract: A method of modifying a physical property of a nanotube comprises subjecting a nanotube having a defined lattice structure orientation to stress conditions sufficient to disrupt the lattice structure and form a dipole of dislocation cores therein, and wherein the dipole of dislocation cores split and propagate in the nanotube in a manner such that the dipole of dislocation cores are separated by at least one domain of modified structure, and wherein the physical property of the nanotube are altered.

Abstract: The present invention relates to a method for production of a metal oxide thin film and a method for production of an arrayed metal oxide functional device, comprising the steps of: preparing a sol containing a material and a solvent; gelating the sol to give a gel member; processing the gel member under a pressure of not less than 0.2 MPa at 100 to 400° C. in a water-vapor-containing atmosphere; and conducting a heat treatment on the water-vapor-processed gel member at 200 to 400° C.

Abstract: A multi-layer preform, includes: (a) a plastic inner liner, comprised of a cylindrical walled body, which may or may not include a tapered annular shoulder portion, and a cylindrical walled neck portion extending upwardly from the body, and (b) a molded outer layer. Prior to the outer layer being molded over the plastic inner liner, at least a portion of the liner is crystallized by a heat treatment process. The molded outer layer may include a means to receive a closure device. When the preform is at an acceptable temperature range for orientation, the multi-layer preform can be blow-molded to form a multi-layer container having improved properties.

Abstract: A mold for molding a core for use in casting hollow parts includes, a lower mold portion and an upper mold portion defining therein a cavity corresponding to the outer surface of the core. The lower mold portion includes a cutout disposed along a parting line defined between the lower mold portion and the upper mold portion and opening onto the cavity. After introduction of a ceramic slurry mixture into the mold the upper mold portion is removable, to expose a first side of the core and a protective flash formed in the cutout. Desirably, a heat shield is positioned over the protective flash and the exposed portion of the parting line of the lower mold portion so that the lower mold portion is not exposed directly to a flame during a preliminary firing to impart sufficient strength to the ceramic core so that the ceramic core may be handled.

Abstract: The invention relates to a process for melt extruding a film layer of a thermoplastic olefin which comprises extruding the film having physical characteristics under process conditions selected by reference to the Draw ratio Dr and the Aspect ratio A such that draw resonance is avoided in which in addition the process conditions are defined by reference to the Deborah number such that the molten polymer is extruded at a Draw ratio of at least 30 in a high elasticity region at a &lgr;c value of characteristic time as defined herein of from 0.001 to 0.6 s, a Deborah number as defined herein in excess of 0.005 and an A value as defined herein lower than 0.8. Narrower ranges of these parameters may be defined for application of the invention to different polymer types.

Abstract: An exterior automotive quality paint coat is laminated to the surface of a plastic car body member of panel. A dry paint transfer film is first laminated to a relatively thin semi-rigid thermoformable resinous backing sheet. The backing sheet side of the resulting laminate is then laminated to a relatively thick thermoformable substrate sheet of the same or a compatible polymeric material. The two sheets are joined by extruding the thick substrate sheet and using the heat of extrusion to then laminate the thin backing sheet to the thicker extruded substrate sheet. The resulting thick sheet laminate is then thermoformed, preferably by first heating the laminate to a forming temperature, followed by vacuum forming the laminate to a three-dimensional shape of the finished automotive part, such as a fascia, ready to put on a vehicle.

Abstract: A method of modifying a physical property of a nanotube includes subjecting a nanotube having a defined lattice structure orientation to stress conditions sufficient to disrupt the lattice structure and form a dipole of dislocation cores therein, and wherein the dipole of dislocation cores split and propagate in the nanotube in a manner such that the dipole of dislocation cores are separated by at least one domain of modified structure, and wherein the physical properties of the nanotube are altered.

Abstract: A method for fabricating adherent, patterned carbon nanotube films is provided. According to the invention, a substrate is patterned with a carbide-forming material, a carbon-dissolving material, or a low melting point metal. Carbon nanotubes are then deposited onto the patterned substrate, but have relatively poor adhesion to either the substrate material or the patterned material. The substrate is then annealed, typically in vacuum, at a temperature dependent on the particular patterning material, e.g., a temperature at which carbide formation occurs, at which carbon dissolution occurs, or at which the low melting point metal melts. The annealing thereby provides an adherent nanotube film over the patterned areas, while the nanotubes deposited onto the non-patterned areas are easily removed, e.g., by blowing, rubbing, brushing and/or ultrasonication in a solvent such as methanol.

Abstract: A polymer film capable of forming an optically anisotropic melt phase is, after having been laminated on a base material capable of supporting the shape of the film during heat treatment, is heat-treated at a temperature of from the thermal deformation temperature Tdef of the film to a temperature lower by &agr; (&agr;=10 to 35° C.) than the melting point Tm of the film until the fusion peak temperature TA of the film attains a temperature which is higher by &bgr; (&bgr;=5 to 30° C.) than the melting point Tm of the film before the heat treatment and is subsequently heat-treated at a temperature of from a temperature not lower than the melting point Tm of the film to a temperature lower than the fuision peak temperature TA for a length of time over which the TA increases by &ggr; (&ggr;=5 to 20° C.), and thereafter the base material is removed to produce the film.

Abstract: A hydrostatic compression method for producing a fancy log with a decorative and complicated external appearance from a primary wood. In the method, a primary wood having a water content adjusted in the range of 10-80 wt % is brought into a softened state, then the softened wood is compressed with hydrostatic pressure by means of liquid as pressurizing medium. Next, the compressed wood is treated with a fixation means to fix the compressed state. The fixation means can be a shaping jig, a mold, heating in a particular temperature range conducted while constraining the volume relation of compressed wood, cooling down below the softening point of the wood while under pressure, compact-packing together with hard particles into a vessel followed by heating, or a primary wood is chemically treated to form a localized wood-plastics composite before applying hydrostatic compression.

Abstract: Particulate inorganic pore material, e.g., controlled pore glass (CPG) embedded porous synthetic resin membrane is prepared by mixing inorganic pore material and an aqueous resin, preferably polytetrafluoroethylene (PTFE), aqueous dispersion to form a paste-like mass, heating the mass at a temperature between 50 to 70° C., and forming the mass into a sheet by calendering. The sheet is then sintered to produce a rigid porous sheet. The membrane may be functionalized, as by silanization. The membrane is useful for the same purposes as controlled pore glass or functionalized controlled pore glass.

Abstract: The invention relates to a method of treating elastic material that is provided with silica embedments to avoid shrinkage, whereby the finished material that is provided with the silica embedments is subjected for a prescribed period of time to temperatures above 40° C. prior to further processing.

Abstract: The present invention relates to medical vascular catheters adapted to be inserted into a blood vessel from an incision through the skin of a patient for introducing ther devices or fluids for diagnostic or therapeutic purposes, and particularly to an improved distal soft tip or segment attachment with a relatively stiff proximal catheter shaft. A tubular sleeve is bonded through the application of pressure and heat to a distal portion of the catheter shaft and a proximal portion of the distal segment of soft distal tip bridging the attachment junction. In the preferred method, the catheter shaft distal end is aligned with the distal segment or soft tip proximal end and the sleeve is fitted over the attachment junction. A heat shrink tube is fitted over the sleeve and adjoining portions of the catheter shaft and the distal segment or distal soft tip and heat is applied.

Abstract: The invention relates to a process for the treatment of cellulosic moulded bodies which are formed from a solution of cellulose in an aqueous tertiary amine oxide, particularly fibers, whereby the moulded bodies are brought into contact with an aqueous solution of a textile auxiliary agent which bears two reactive groups in the alkaline milieu. The invention is characterised in that as the textile auxiliary agent, a compound of formula whereby X is halogen, R═H or an ionic residue and n=0 or 1, respectively a salt of this compound is used. The invention also relates to the use of compounds of this formula to reduce the tendency to fibrillate and to increase the UV absorption of solvent-spun fibers.

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, by crushing the rigid foam so obtained and by subjecting the flexible foam so obtained to a heat treatment. Flexible foams are obtained which do not show a major glass transition temperature between −100° C. and +25° C.

Abstract: A device useful for localized delivery of a therapeutic material is provided. The device includes a structure including a porous material; and a water-insoluble salt of a therapeutic material dispersed in the porous material. The water-insoluble salt is formed by contacting an aqueous solution of a therapeutic salt with a heavy metal water-soluble salt dispersed throughout a substantial portion of the porous material. The porous material can be made of a polymer other than fibrin with fibrin incorporated into the pores, which can be the only layer of polymeric material on the medical device (e.g., stent). A new method for preparing a porous polymer material on a medical device.

Abstract: A process for the preparation of a cellulosic fibrous aggregate, comprising a softening stage, a dewatering stage and a curing stage, whereby in the softening stage a section of cellulosic fibrous material is exposed to the action of a liquid aqueous softening agent at elevated temperature and at a pressure of at least the equilibrium vapor pressure of the softening agent at the operating temperature, and whereby part of the heat required to raise the temperature of the starting material to the operating temperature of the softening stage, is obtained, by heat-exchange contact, from an aqueous stream, the initial temperature of which is substantially equal to the said operating temperature.

Abstract: The present invention discloses and claims a novel process for the formation of high denier as-spun and heat-treated filaments of a thermotropic liquid crystalline polymer. Preferred embodiments include process for the formation of as-spun and heat treated monofilaments of a few wholly aromatic polyesters and polyesteramides. The process involves (a) heating of a thermotropic liquid crystalline polymer to above its melting transition temperature; (b) passing said molten polymer through an extrusion chamber equipped with an extrusion capillary of an aspect ratio of greater than about 1 and less than about 15 to form a filament; and (c) winding the filament at a draw-down ratio of at least about 4. The filaments so formed are of at least 50 denier per filament (dpf) and feature essentially uniform molecular orientation across the cross-section. In a final optional step, the filaments are heat treated in stages to form filaments exhibiting excellent tensile properties.