Abstract: An apparatus for making spunbonded nonwovens has a spinneret for emitting continuous thermoplastic filaments in a filament-travel direction, a cooling chamber downstream in the direction from the spinneret for cooling the spun filaments with cooling air, two manifolds on opposite sides of the cooling chamber opening transversely of the direction into the cooling chamber, and a respective conduit having a conduit cross-sectional area and connected to each manifold for feeding cooling air thereto. The conduit cross-sectional area increases toward the manifold to a manifold cross-sectional area, and manifold cross-sectional area is at least twice as large as the conduit cross-sectional area. At least one flow straightener is provided upstream from the cooling chamber in each manifold for orienting air flow in an air-flow direction, and at least one perforated planar homogenizing element is provided in each manifold for homogenizing the cooling air flow.

Abstract: Techniques for melt spinning and cooling of multifilament polyamide threads are described. The process involves multiple filament bundles spun alongside one another and cooled down separately by streams of cooling air flowing radially from the outside to the inside. Streams of cooling air are produced from a blowing chamber connected to a pressure source. Exhaust gases that occur during the spinning are removed through exhaust openings before the cooling of the filament bundles. An air pressure is set within the blowing chamber in such a way that the exhaust gases in the vicinity of the filament bundles are blown out through the exhaust openings from the inside outwards. A blowing box is assigned a pressure setting means for setting an air pressure within the blowing chamber, by which an air pressure for blowing out the exhaust gases can be set at the exhaust openings of a connection adapter.

Abstract: The present invention relates to a drawn PET fiber which has good dimensional stability, thereby increases the high speed driving performance of a tire, a PET tire cord, their preparation methods, and a tire including the same. The drawn PET fiber may includes 90 mol % or more of PET and may be a fiber of which a creep rate is 5.5% or less when the drawn PET fiber is fixed under the initial load of 0.01 g/d and is kept for 24 hours under the load of 0.791 g/d and the temperature of 100° C. Furthermore, the PET tire cord may be a cord of which a creep rate is 4.0% or less when the PET tire cord is fixed under the initial load of 0.01 g/d and is kept for 24 hours under the load of 0.791 g/d and the temperature of 100° C.

Abstract: Disclosed is a PET tire cord which has a flat spot index (FSI) defined by the following Calculation Formula 1 of 5.0% or less: Flat Spot Index (FSI)(%)=(L1?L2)/L0×100??Calculation Formula 1 wherein, L0 is an initial length of the tire cord, L1 is a length of the tire cord that is measured after providing a load corresponding to 13% of the strength at break of the cord for 5 minutes at 120° C. and cooling the same to 24° C. while maintaining the load, and L2 is a length of the tire cord that is measured after providing a load corresponding to 13% of the strength at break of the cord for 5 minutes at 120° C. and cooling the same to 24° C. while remaining the load of 0.01 g/d only.

Abstract: The present invention relates to a drawn PET fiber that can provide a cap ply cord and the like showing more improved modulus and good dimensional stability, a PET tire cord, and a tire including the same. The drawn PET fiber may be a fiber including 90 mol % or more of PET, of which the crystallinity is 53% or more, the amorphous orientation factor (AOF) is 0.15 or less, and the birefringence index is 0.14 to 0.16, after heat-treating the same at 230° C. for 1 minute under the initial load of 20 g/1000 d.

Abstract: Methods for making high quality polyimide fibers suitable for continuous industrial production are described. Polyimide fibers are continuously prepared from a polyamic acid solution through sequentially spinning the polyamic acid solution by either a wet or a dry-wet process, coagulating, drying or drying after washing, thermally treating and stretching the resulting polyamic acid fibers to obtain polyimide fibers, and winding polyimide fibers as prepared into rolls.

Abstract: A graphene ribbon fiber manufacturing process, where a coagulation medium flows in the same direction as the graphene ribbon fibers. The process for spinning graphene ribbon fibers starts with unzipping carbon nanotubes to form graphene ribbons, purifying and drying the graphene ribbons and subsequent dissolving of the graphene ribbons in a suitable solvent, preferably a super acid to form a spin-dope. The spin-dope is spun such that the accrued fibers are guided into a coagulation medium, also known as anti-solvent, where the spun or accrued fibers are coagulated. The coagulated graphene ribbon fibers are stripped, neutralized and washed and wound on bobbins.

Abstract: A bulk of polyester polymer particles comprising polyester polymer comprising greater than 75% virgin polyester polymer, the particles having: A) an It.V. of at least 0.72 dl/g, and B) 10 ppm or less of residual acetaldehyde; and C) at least two melting peaks, wherein one of said at least two melting peaks is a low peak melting point within a range of 140° C. to 220° C. and having a melting endotherm area of at least the absolute value of 1 J/g. The particles may also have a degree of crystallinity within a range of 20% and a maximum degree of crystallinity Tcmax defined by the equation: Tcmax=50%?CA?OH where CA is the total mole % of all carboxylic acid residues other than terephthalic acid residues, based on 100 mole % of carboxylic acid residues, and OH is the total mole % of all hydroxyl functional compound residues other than ethylene glycol residues, based on 100 mole % of hydroxyl functional compounds residues.

Abstract: A method of synthesizing mechanically resilient titanium carbide (TiC) nanofibrous felts comprising continuous nanofibers or nano-ribbons with TiC crystallites embedded in carbon matrix, comprising: (a) electrospinning a spin dope for making precursor nanofibers with diameters less than 0.5 J.Lm; (b) overlaying the nanofibers to produce a nanofibrous mat (felt); and then (c) heating the nano-felts first at a low temperature, and then at a high temperature for making electrospun continuous nanofibers or nano-ribbons with TiC crystallites embedded in carbon matrix; and (d) chlorinating the above electrospun nano-felts at an elevated temperature to remove titanium for producing carbide derived carbon (CDC) nano-fibrous felt with high specific surface areas.

Abstract: The present disclosure provides polyimide fibers with kidney-shaped cross-section and their preparation methods thereof, falling within the technical field of polyimide fiber. Polyimide fibers with kidney-shaped cross-sections are prepared by a continuous, integrated approach, starting from a polyamic acid solution prepared by reacting an aromatic dianhydride with an aromatic diamine. PAA nascent fibers with kidney-shaped cross-sections are obtained by adopting a spinneret having circular orifices under wet spinning process. The kidney-shaped cross-sections are obtained by varying the processing condition, including spinning speed, coagulation bath composition, coagulation temperature, and depth of coagulation bath. After washing and drying, polyamic acid nascent fibers are converted to polyimide fibers with kidney-shaped cross-sections under thermal curing. The integrated preparation methods are suitable for mass industrial production.

Abstract: A method of manufacturing a polyacrylonitrile fiber includes a spinning process in which a spinning dope including polyacrylonitrile is spun; a first drawing process; a drying process; and a second hot drawing process in this order.

Abstract: A production method for a carbon fiber precursor fiber bundle and a production apparatus of the carbon fiber precursor fiber bundle. A carbon fiber precursor fiber bundle that has a degree of intermingle of 1 m?1 or less between small tows, consists of substantially straight fibers without imparted crimp, a tow of which straight fibers has a moisture content of less than 10% by mass when housed in a container, and has a widthwise dividing capability to maintain a form of a single aggregate of tows when housed in a container, taken out from the container and guided into a firing step, and to divide into a plurality of small tows in the firing step by the tension generated in the firing step.

Abstract: A method of preparing meta-aramid fibers includes the operations of polymerization, neutralization and spinning using m-phenylenediamine and isophthaloyl chloride as raw materials, wherein the neutralizing agent is added in an amount that is sufficient only for neutralizing a part of hydrogen chloride, so that the resultant spin dope of polyisophthaloyl metaphenylene diamine contains salts produced by the neutralization reaction and a part of unneutralized hydrogen chloride. The method of the invention has a short production line with reduced amount of the neutralizing agent, therefore both the costs of raw materials and the production energy consumption are saved. The fibers prepared according to the method of the invention have reduced gray scale to improve the electrical insulation properties of the fibers.

Abstract: A technique with which a nanofibrous resin spun by electrospinning can be introduced into inner parts of fibers. The process for fiber composite material production is a process which comprises spinning a nanofibrous resin toward split fibers continuously conveyed along a given conveyance route and thereby combining the split fibers with the resin to produce a fiber composite material. The process involves a resin spinning step in which the nanofibrous resin spun with an electrospinning device is flown toward the split fibers. In the resin spinning step, the direction in which the nanofibrous resin proceeds is made to be the same as the conveying direction of the split fibers by blowing an air stream from a blower on the nanofibrous resin.

Abstract: A colored high strength polyethylene fiber, preparation method and use thereof are provided, which are in the high molecular material field. The surface of said high strength polyethylene fiber is chromatic, grey or black. The strength of said high strength polyethylene fiber is 15-50 g/d, its modulus is 400-2000 g/d. The product of the present invention is colored, so it can be well applied to civil and military field. The preparation method of present invention has some advantages that technological process is simple, production efficiency is high, cost of production is low, performance of made fiber is excellent, and use-cost is reduced, compared with the prior art.

Abstract: Disclosed are water-dispersible fibers derived from sulfopolyesters having a Tg of at least 25° C. The fibers may contain a single sulfopolyester or a blend of a sulfopolyester with a water-dispersible or water-nondispersible polymer. Also disclosed are multicomponent fibers comprising a water dispersible sulfopolyester having a Tg of at least 57° C. and a water non-dispersible polymer. The multicomponent fibers may be used to produce microdenier fibers. Fibrous articles may be produced from the water-dispersible fibers, multicomponent fibers, and microdenier fibers. The fibrous articles include water-dispersible and microdenier nonwoven webs, fabrics, and multilayered articles such as wipes, gauze, tissue, diapers, panty liners, sanitary napkins, bandages, and surgical dressings. Also disclosed is a process for water-dispersible fibers, nonwoven fabrics, and microdenier webs.

Abstract: A method of continuous curing and post-curing of a plurality of extruded strands is provided. A plurality of extruded strands is wrapped through a plurality of spindle units rotatably connected to a rigid frame structure. A plurality of dual spindles are provided in a plurality of upper and lower spindle units, wherein each dual spindle comprises a free spinning roller and a driven roller. A chamber that comprises a dual function chamber configured for heating and cooling is supported on the rigid frame structure. The plurality of extruded strands is continuously transferred between the upper spindle units and the lower spindle units such that the plurality of extruded strands runs in a vertical fashion that continuously alternates between the lower spindle units and the upper spindle units. Each of the plurality of strands is transferred independently of each other and continuously passed through the chamber for continuous curing and post-curing.

Abstract: The present invention concerns a process and apparatus for spinning polymer filaments comprising extruding a polymer solution to form one or more filaments into an air gap above a coagulation liquid, where the filaments are subject to strain; forming a downward stream of liquid and filaments by contacting the polymer solution with a coagulation liquid; passing the filaments and liquid through a quench tube; contacting the liquid with a surface such that the downward force of gravity on the liquid does not increase the strain of the filaments in the air gap; and separating the liquid from the filaments.

Abstract: The present invention provides a method of preparing a flame retardant polyester fiber that makes it possible to prepare a flame retardant polyester fiber having excellent shape stability while preventing a lumping phenomenon and reducing powder generation and discoloration during the preparing process of the flame retardant polyester fiber, and a flame retardant polyester fiber prepared therefrom.

Abstract: Conjugate fibers are prepared in which at least one segment is a mixture of a high-D PLA resin and a high-L PLA resin. These segments have crystallites having a crystalline melting temperature of at least 200° C. At least one other segment is a high-D PLA resin or a high-L PLA resin. The conjugate fibers may be, for example, bicomponent, multi-component, islands-in-the-sea or sheath-and-core types. Specialty fibers of various types can be made through further downstream processing of these conjugate fibers.

Abstract: A process for preparing ultra-high molecular weight poly(alpha-olefin) (UHMWPO) multi-filament yarns having improved tensile properties at higher productivity. The process includes drawing a solution yarn, then drawing a gel yarn and then drawing a dry yarn continuously in sequence to form a partially oriented yarn, winding up the partially oriented yarn, unrolling the yarn, drawing the partially oriented yarn to form a highly oriented yarn, cooling the highly oriented yarn under tension and winding up the highly oriented yarn.

Abstract: The present invention relates to a continuous, multicellular, hollow carbon fiber wherein the fiber structure includes a substantially hollow fiber and multiple internal walls defining multiple integral internal hollow fibers such that the fiber structure comprises a honeycomb-like cross section.

Abstract: An apparatus for continuous curing of a plurality of extruded strands can include a rigid frame structure formed by interconnecting a plurality of rigid frame members. A rigid top plate member and a rigid bottom plate member are attached to the rigid frame structure. A plurality of upper spindle units is rotatably attached to the rigid top plate member and a plurality of lower spindle units is rotatably attached to the rigid bottom plate member. A pair of drive motors is attached to the rigid frame structure. A gear assembly attached to the rigid frame structure is operably engaged to the pair of drive motors and a chamber is supported on the rigid frame structure for curing the plurality of extruded strands. The pair of drive motors drives the gear assembly to continuously pass the plurality of extruded strands through the chamber for continuous curing and post-curing.

Abstract: Disclosed are water-dispersible fibers derived from sulfopolyesters having a Tg of at least 25° C. The fibers may contain a single sulfopolyester or a blend of a sulfopolyester with a water-dispersible or water-nondispersible polymer. Also disclosed are multicomponent fibers comprising a water dispersible sulfopolyester having a Tg of at least 57° C. and a water non-dispersible polymer. The multicomponent fibers may be used to produce microdenier fibers. Fibrous articles may be produced from the water-dispersible fibers, multicomponent fibers, and microdenier fibers. The fibrous articles include water-dispersible and microdenier nonwoven webs, fabrics, and multilayered articles such as wipes, gauze, tissue, diapers, panty liners, sanitary napkins, bandages, and surgical dressings. Also disclosed is a process for water-dispersible fibers, nonwoven fabrics, and microdenier webs.

Abstract: Exemplary embodiments provide core-sheath nanofibers produced by coaxial electrospinning, fuser members comprising core-sheath nanofibers, and methods for forming core-sheath nanofibers that can include a core solution comprising a high performance polymer and sheath solutions comprising a solvent-soluble fluoropolymer or solvent-insoluble fluororesins and a sacrificial polymeric binder.

Abstract: PLA stereocomplex fibers are made by separately melting a high-D PLA starting resin and a high-L starting resin, mixing the melts and spinning the molten mixture. Subsequent heat treatment introduces high-melting “stereocomplex” crystallinity into the fibers. The process can form fibers having a high content of “stereocomplex” crystallites that have a high melting temperature. As a result, the fibers have excellent thermal resistance. The process is also easily adaptable to commercial melt spinning operations.

Abstract: The present invention provides a processing method of the natural cellulose fiber with feature for enhancing the capability of antifungi, antibacteria and deodorization. The procedure is that firstly modify and reduce the properties of the natural chitosan of high polymer material to nanometer scale; secondly dunk the chitosan into the syrup-like mixture of wood pulp and NMMO solvent to yield quasi-dope; thirdly dehydrate the quasi-dope of paste mixture to form the mud-like dope; fourthly spin the dope by dryjet wet spinning method; fifthly regenerate the filament in coagulation bath, water rinse and dry; finally water rinse, dry, apply the lubricant to finish. The water soluble chitosan, which has been treated by property modification and reduced to nanometer scale, can effectively and completely solve in the cellulose of low DP to offer wider extent of selection in the DP and better flexibility of adding percentage in content of modified chitosan.

Abstract: A process for the preparation of polymer yarns from ultra high molecular weight homopolymers or copolymers, wherein the process includes the following steps: (a) preparing a suspension of a homopolymer or copolymer and a spinning or gelling solvent of a non polar nature at a weight of homopolymer or copolymer to solvent ratio from 2/98 to 30/70, wherein said ultra high molecular weight homopolymer or copolymer is reactor bimodal or multimodal; (b) feeding said homopolymer or copolymer suspension to an extruder; (c) extruding said suspension under gel forming conditions, at a temperature in excess of 150° C., and under inert conditions; (d) spinning the gel obtained from the extrusion so as to obtain non-stretched filaments with diameters of at least 1 mm, at a temperature in excess of 150° C.

Abstract: Blending of thermoplastic polyester with fiber-forming polyamide in the production of melt-colored melt-spun fibers results in improved color strength and aesthetics, and dimensional stability.

Abstract: A process for the preparation of polymer yarns from ultra high molecular weight homopolymers or copolymers which includes the steps of preparing a suspension of a homopolymer or copolymer and a spinning or gelling solvent, extruding the suspension with the formation of a gel, spinning the gel to obtain non-stretched filaments or yarns, cooling the non-stretched filaments or yarns, feeding the non-stretched filaments or yarns, to an extractor together with the feed of an organic extraction solvent, extracting the non-polar long chain solvent impregnated in the yarns, drying the non-stretched filament bundles or yarns, and stretching said dry yarns at a temperature in excess of 80° C.

Abstract: An improved process for the preparation of a cellulose solution for spinning of fibers, filaments or films therefrom comprising the steps of: a) activating cellulose in a mixture containing said cellulose, tertiary amine oxide solvent and water for a period sufficient to allow a swelling of the cellulose by introduction therein of water present in said mixtures, the temperature of said activation step and concentration of solvent being such that the solvent is not converted into its monohydrate state during the step of activation; b) the cellulose mixture being subjected to the steps of dissolution of cellulose in the solvent by heating for removal of water so as to convert the solvent into at least its monohydrate form so as to cause a dissolution.

Abstract: The present invention relates to a process for producing a polyphenylene sulfide multifilament yarn, a polyphenylene sulfide multifilament yarn and the use of a polyphenylene sulfide multifilament yarn. The process for producing a polyphenylene sulfide multifilament yarn is characterized in that only after time period between 0.1 sec and 0.3 sec after leaving the spinneret the filaments of the spun yarn are subjected to an active cooling stage. The Polyphenylene sulfide multifilament yarn having a filament linear density of 5 dtex to 30 dtex, an overall linear density of 500 dtex to 2500 dtex, a breaking tenacity in the range of 50 cN/tex to 80 cN/tex and an elongation at break of 8% to 16% for a yarn with a breaking tenacity in the range of 60 cN/tex to 80 cN/tex and an elongation at break of 16% to 30% for a yarn with a breaking tenacity in the range of 50 cN/tex to 60 cN/tex.

Abstract: Methods and apparatus for meltblowing utilize an auxiliary manifold to dispense a fluid between an orifice of a die that is expelling polymeric fibers and an exit of a duct that is dispensing a secondary flow of gas onto the fibers. The fluid dispensed from the auxiliary manifold reduces a recirculation zone of the secondary flow between the exit and the orifice that, absent the fluid from the manifold, results in errant fibers that are blown back into the face of the die by the recirculating secondary flow.

Abstract: A process for preparing ultra-high molecular weight poly(alpha-olefin) (UHMWPO) multi-filament yarns having improved tensile properties at higher productivity. The process includes drawing a solution yarn, then drawing a gel yarn and then drawing a dry yarn continuously in sequence to form a partially oriented yarn, winding up the partially oriented yarn, unrolling the yarn, drawing the partially oriented yarn to form a highly oriented yarn, cooling the highly oriented yarn under tension and winding up the highly oriented yarn.

Abstract: A method for spinning a multifilament yarn from a thermoplastic material, where the filament bundle is cooled below the spinneret in a first cooling zone, first of all by means of at least one transverse blowing operation with a gaseous cooling medium and by means of an extraction means for the gaseous cooling medium which lies opposite said transverse blowing means, and subsequently the filament bundle is cooled further in a second cooling zone below the first cooling zone by automatic suction of gaseous cooling medium which is situated in the vicinity of the filament bundle.

Abstract: A method for producing a continuous filament made up of nanofibers is disclosed. A ribbon-shaped nanofiber web is prepared by electrospinning a polymer spinning solution onto a collector 7 applied with a high voltage, the collector 7 consisting of (I) an endless belt type nonconductive plate 7a with grooves having a predetermined width (u) and depth (h) formed at regular intervals along a lengthwise direction and a conductive plate 7b inserted into the grooves of the nonconductive plate, and then the nanofiber web is isolated (separated) from the collector 7, focused, drawn and wound. A continuous filament (yarn) made up of nanofibers can be produced by a simple and continuous process by providing a method for continuously producing a filament (yarn) by an electrospinning technique without a spinning process. The focusability and the drawability can be greatly improved by orienting nanofibers well in the fiber axis direction.

Abstract: This invention provides a method of producing chitosan non-woven fabrics and an apparatus thereof. At first, a chitosan acidic solution is extruded to form a chitosan fibrous stream. Then, a solidifying agent is ejected to form a solidifying agent stream. The solidifying agent stream and the chitosan fibrous stream are combined to form a pre-solidified chitosan fiber. Then, high-pressure air is ejected on the pre-solidified chitosan fiber to stretch the pre-solidified chitosan fiber. Finally, the chitosan fibers are collected to form chitosan non-woven fabrics.

Abstract: The present invention concerns a process for making a polyareneazole multifilament yarn comprising: a) extruding a solution comprising polyareneazole polymer and polyphosphoric acid through a plurality of orifices to produce filaments; b) forming a multifilament yarn from said filaments; c) hydrolyzing at least some of the polyphosphoric acid in the yarn by heating the yarn to a temperature above about 120° C. for up to about two minutes; d) washing at least some of the hydrolyzed polyphosphoric acid from the yarn; e) drying the washed yarn; f) optionally, heating the yarn above about 300° C., and g) collecting the yarn at a speed of at least about 50 meters per minute.

Abstract: A process for producing polyacrylonitrile-base precursor fibers for production of carbon fibers, which comprises spinning a spinning dope containing 10 to 25 wt % of a polyacrylonitrile-base polymer having an intrinsic viscosity of 2.0 to 10.0 by extruding the spinning dope from a spinneret by a wet spinning or a dry wet spinning method, drying and heat-treating fibers obtained by the spinning, and then steam drawing the resulting fibers, wherein the linear extrusion rate of the polyacrylonitrile-base polymer from the spinneret is 2 to 15 m/min. Carbon fibers which are produced by stabilizing-carbonizing treatment of the polyacrylonitrile-base precursor fibers and which have a strand tensile modulus of 320 to 380 GPa and a conduction electron density of 3.0×1019 to 7.0×1019 spins/g as determined by electron spin resonance.

Abstract: A method is provided for spinning a multifilament thread from a thermoplastic material, including the steps of extruding the melted material through a spinneret with a plurality of spinneret holes into a filament bundle with a plurality of filaments, winding the filaments as thread after solidifying, and cooling the filament bundle beneath the spinneret, whereby in a first cooling zone the gaseous cooling medium is directed in such a way that it flows through the filament bundle transversely, the cooling medium leaving the filament bundle practically completely on the side opposite the inflow side, and in a second cooling zone beneath the first cooling zone, the filament bundle being cooled further essentially through self-suction of the gaseous cooling medium surrounding the filament bundle.

Abstract: Methods for preparation of high strength yarns having superior yarn-to-yarn uniformity of denier, tenacity and tensile modulus and uniform unidirectional fibrous sheets. Ballistic composites prepared from these yarns and fibrous sheets have improved uniformity of ballistic resistance. The drawn yarns, fibrous sheets and articles made therefrom are more uniform than the prior art and are useful in applications requiring impact absorption and ballistic resistance, such as body armor, helmets, breast plates, helicopter seats, spall shields; composite sports equipment such as kayaks, canoes, bicycles and boats; and in fishing line, sails, ropes, sutures and fabrics.

Abstract: The present invention is a process for producing a fiber, comprising: melt-extruding polyhydroxyalkanoic acid; solidifying the polyhydroxyalkanoic acid by quenching it to its glass transition temperature +15° C. or less, to form an amorphous fiber; cold-drawing the amorphous fiber at its glass transition temperature +20° C. or less; and subjecting the fiber to heat treatment under tension. The present invention can provide: a process for producing a fiber with high strength, and the fiber produced through the process; and a process for producing a fiber with high strength and high modulus of elasticity and the fiber with high strength and high modulus of elasticity produced through the process, regardless of molecular weights of PHAs varying depending on origins such as a wild type PHAs-producing microorganism product, a genetically modified product, and a chemical product.

Abstract: A filter element in the form of a nonwoven self-supporting filtration web having rows of folded or corrugated spaced-apart pleats, the web containing continuous thermoplastic fibers a majority of which are aligned at 90°±20° with respect to the row direction. The filter element can be made by forming rows of pleats in such a nonwoven web and cutting the web to a desired size and shape. The filter elements can provide improved mechanical and filtration properties and can exhibit reduced susceptibility to pleat deformation and the loss of space between pleats.

Abstract: A process for preparing superior carbon fiber including a step of rapid imbibation of densification activator from an aqueous bath; and product prepared therefrom.

Abstract: A fiber and a process for obtaining same from a high-modulus polyethylene, extrudable in state-of-the-art equipment and in the absence of previous solubilization in any kind of organic solvent is described, the process comprising providing such a polyethylene, introducing it in a state-of-the-art extruder, extruding it according to a temperature pattern, obtaining an extrudate that is directed to a cooling bath to have its temperature reduced, then directing the extrudate to a first stretcher where it is stretched or drawn into a fiber of improved tenacity, at a first velocity v1, then heating the fiber at nearly 90° C. and then directing said fiber to a second stretcher to be drawn at a final velocity v2, wherein v1<v2, at a draw ratio of 2/1 until 65/1. The tenacity of the polyethylene fiber obtained by the said process attains at least 4 gf/den, which makes it useful to naval and offshore applications.

Abstract: Gel-spun multi-filament polyethylene yarns possessing a high degree of molecular and crystalline order, and to the drawing methods by which they are produced. The drawn yarns are useful in impact absorption and ballistic resistance for body armor, helmets, breast plates, helicopter seats, spall shields, and other applications; composite sports equipment such as kayaks, canoes, bicycles and boats; and in fishing line, sails. ropes, sutures and fabrics.

Abstract: This invention relates to a method of preparing cellulose solution which is homogeneous at relatively low temperature, in which a small amount of cellulose powder or polyvinylalcohol is dissolved in the liquid-state, concentrated N-methylmorpholine-N-oxide (hereinafter, referred to as ‘NMMO’) so as to lower the solidifying temperature of NMMO, and then, the resulting solution and cellulose powder are fed into an extruder so as to be mixed, swollen and melted in the extruder.

Abstract: The present invention relates to polybenzazaole (PBZ) fibers and processes for the preparation of such fibers. The invention further relates to yarns, fabrics, and articles incorporating fibers of this invention, and processes for making such yarns, fabrics, and articles.

Abstract: A spun polyester fiber, a drawn polyester yarn, and methods for making them. Polyethylene terephthalate yarn is prepared by extruding a molten melt-spinnable polyethylene terephthalate having an intrinsic viscosity of at least about 0.8 through a shaped extrusion orifice having a plurality of openings to form a molten spun yarn; solidifying gradually said molten spun yarn by passing said molten spun yarn through a solidification zone which comprises (i) a retarded cooling zone and (ii) a cooling zone adjacent said retarded cooling zone where, in said cooling zone, said yarn is rapidly cooled and solidified in a gaseous atmosphere; withdrawing at sufficient speed said solidified yarn from said solidification zone to form a crystalline partially oriented yarn; and hot drawing said crystalline partially oriented yarn at a total draw ratio between about 1.5/1 and about 2.5/1 to produce a drawn yarn having an effective crosslink density (N) between about 10×1021 and about 20×1021 crosslinks per cubic centimeter.

Abstract: A method is provided for simultaneous spin-drawing of continuous yarns consisting of one or more filaments, comprising the steps in which a melt of a thermoplastic material is fed to a spinning device, the melt is extruded through a spinneret by means of extrusion openings with the formation of continuous yarns, the continuous yarns are cooled by feeding them through a first and a second cooling zone, wherein the continuous yarns are cooled essentially by a stream of air on passing through the first cooling zone and essentially by a fluid, consisting wholly or partly of a component that is liquid at room temperature, on passing through the second cooling zone, and the continuous yarns are then dried, subsequently drawn and wound up by means of winding devices, the method being distinguished in that the continuous yarns are fed through the first and second cooling zones at a speed of up to 500 m/min and that the residence time of the continuous yarns within the first cooling zone is at least 0.1 sec.