Abstract: A process for producing aromatic polyester fibers having a high strength and resistances to fibrillation, buckling, abrasion and fatigue. The process comprises spinning aromatic polyesters capable of forming anisotropic melts and heat treating the as-spun fibers, the heat treatment being characterized by a combination of a first heat treatment in an inert atmosphere and a successive heat treatment in an active atmosphere.

Abstract: The method for producing dimensionally stable, low-shrinkage, chemically modified industrial polyester yarns by melt spinning at speeds of 1000 to 4000 m/min. utilizes a copolymer containing at least 85 percent by weight polyethylene terephthalate units and comonomers. During polyester production to lower the thermal shrinkage one or more conformationally fixed linear difunctional comonomers are added to the polymer melt. These difunctional comonomers have the general formula, X'--R--X, where R is an unsaturated linear alkyl group having from three to ten carbon atoms or a cycloalkyl or aromatic group with 6 or more carbon atoms, and X and X' are, independently, OR' or CPPR", and R'=H or an alkyl group and, independently, R" is also H or an alkyl group.

Abstract: In the production of irregular non-woven material sheets of synthetic filaments, the warp from spinnerets is drawn off by means of a draw-off device and then deposited on a substrate. To avoid tangling of the individual filaments, they are guided along a nozzle wall formed by slot nozzles stacked on top of each other and forming a draw-off device. The slot nozzles as well as the air compressor are operated polytropically. The deposit of the warp on the substrate is accomplished by a flip-flop cross winding.

Abstract: A process for the preparation of thermoplastic fibers which comprises:(a) spinning a solution of an alternating copolymer of an olefinically unsaturated compound and carbon monoxide, having a number average molecular weight of at least 5000, to fibers through a spinning aperture, said solution having a polymer content in the range of from 0.1-50% m(b) submitting the thus obtained fibers to a solvent-removal treatment to remove substantially all the solvent, and(c) stretching the thus obtained substantially solvent-free fibers in an environment having a temperature between the glass-transition temperature of said polymer and (T+20).degree. C., when T is the crystalline melting point of the polymer.

Abstract: An improved process for flash-spinning polyethylene plexifilamentary film-fibril strands is provided. The strand is flash-spun from a non-chlorofluorocarbon mixture of polyethylene, an organic solvent and water.

Abstract: An improved process for flash-spinning plexifilamentary film-fibril strands from fiber-forming polyolefins is provided. A polyolefin is mixed to form a solution of 18 to 33 percent polyolefin by weight of the solution, 42 to 73 perceny methylene chloride by weight of the solution and 9 to 25 percent carbon dioxide by weight of the solution. The mixture is then flash-spun into substantially dry plexifilamentary strands.

Abstract: A process for producing a polyhalogenated microporous film having a very narrow pore size distribution and good temperature and chemical resistance. The process involves blending a polyhalogenated copolymer with a polyethyloxazoline utilizing a solvent which is a nonsolvent for the polyhalogenated copolymer but a solvent for polyethyloxazoline, forming a film from the blend, drying the film, heating the film to a temperature at or above the melting point of the polyhalogenated copolymer and under conditions such that the microparticulate particles at their points of mutual contact will neck together to form a relatively continuous matrix and extracting the polyethyloxazoline from the film utilizing a solvent for the binder particle to form a microporous film.

Abstract: The present invention pertains to a process for the production of an article comprising a polymer itself comprising poly(phenylene sulfide), which process comprises:A. contacting poly(phenylene sulfide) with at least one organic compound, consisting essentially of carbon and hydrogen, and optionally oxygen, nitrogen, sulfur, halogen, or mixtures thereof, having a molecular weight of between about 110 and 450 daltons and having at least one six membered aromatic ring structure, which compound is stable at a temperature of between 160.degree. and 400.degree. C. at ambient pressure, at a temperature of between about 160.degree. and 400.degree. C. at ambient pressure for a time effective to dissolve greater than 10 percent by weight of the poly(phenylene sulfide) present, with the proviso that when oxygen is present, the organic compound is not diphenyl oxide or substituted diphenyl oxide;B. forming the solution of poly(phenylene sulfide) and solvent of Step (A) into a desired article configuration;C.

Abstract: Pourable particles of normally soft and tacky plastic materials are formed by extruding the molten plastic material into contact with a cooling fluid containing a non-sticky material that is compatible with the plastic material, cutting the plastic material into particles, separating these particles from the cooling fluid, and contacting these particles with a second compatible non-sticky material.

Abstract: A multifilament type plastic optical fiber having a substantially rectangular cross-section and an islands-in-the-sea structure in which 100 to 10,000 islands are arranged in the sea, wherein the respective islands have a substantially circular cross-section and a core-sheath structure, the islands are arranged in a zigzag-stacked structure, the core occupaney ratio in the multifilament type optical fiber cores section is at least 50% and the brightness index value I which is defined by the following (1), is at least 4.5.times.10.sup.-2 : ##EQU1## wherein S stands for the core occupancy ratio in the multifilament type optical fiber, .alpha. stands for the transmission loss (dB/m) per meter of the multifilament type optical fiber, NA stands for the numeral apertures, and L stands for the length (m) of the used optical fiber.

Abstract: An improved process is provided for flash-spinning plexifilamentary film-fibril strands of polyethylene. A portion of the conventionally used trichlorofluoromethane ("F-11") is replaced with at least one isomer of dichlorotrifluoroethane to reduce the ozone depletion hazard.

Abstract: A process for producing zero pilling polyester filaments, staple, yarn and fabrics is disclosed. The process steps include: providing a polyester polymer containing a structure opener and a monomer containing a sulfonate group; forming the polymer into fibers; hydrolyzing those fabrics; and arresting the hydrolysis by the addition of a metal ion source.

Abstract: In the preparation of a film by melt-extrusion process of thermoplastic polyimide, static charge is applied to a molten film, primary cooling is carried out by adhering the film to a cooling roller having a surface temperature in the range of from the glass transition temperature of said polyimide -50.degree. C. to the glass transition temperature -15.degree. C., the film is successively cooled to 60.degree. C. and less without bringing the film into contact with rollers, and is taken up under tension to give a polyimide film.

Abstract: Process for making aromatic polyamide fibers of high hydrolytic stability is disclosed. The polyamide is a copolymer including chloroterephthalamide or a blend of homopolymers including one with chloroterephthalamide; and the fibers are dried under tension or heat treated.

Abstract: A method is proposed for the preparation of pitch-based carbon fibers having excellent mechanical properties or , in particular, a surprisingly high knot strength much higher than that of PAN-based carbon fibers. The method comprises the steps of melt-spinning of starting pitch material, infusibilization of the pitch fibers by oxidation and carbonization of the infusibilized pitch fibers in an inert atmosphere. The improvement of the inventive method consists in the infusibilization treatment of pitch fibers under controlled conditions so as to effect preferential oxidation of the surface layer to such an extent that the value m=(O.sub.1s /C.sub.1s)/(O/C) is at least 2, in which O.sub.1S /C.sub.1S is the molar ratio of the oxygen content to the carbon content in the surface layer as determined by the ESCA method and O/C is the molar ratio or the oxygen content to the carbon content for the infusibilized pitch fiber as a whole.

Abstract: A method of separating filaments from a clump thereof in a liquid flow from each other by sub-dividing the flow across its lateral extent to pass through an array of a plurality of filament separating channels having a cross-section at least large enough to accommodate the cross-section of the clumps such that flow along the channels imparts a shearing force to filaments at the edge of the flow in the channel to separate these axially from each other and from filaments at the center of the clump.

Abstract: A process for producing microcellular foamed articles wherein a low pressure compressible, inert gas such as nitrogen is used as a foaming agent.

Abstract: A melt-spinning process for spinning polymeric filaments at a spinning speed controlled by a positive mechanical withdrawal means that increases the speed of the filaments to above 7,000 meters/minute whereby a drawing and necking down of the filaments occur below the spinning pack, directing a gas into a zone extending from the spinning pack to a location between the spinning pack and the withdrawal means, maintaining the zone under superatmospheric pressure of less than 0.03 kg/cm2 and increasing the velocity of the gas as it leaves the zone to a level greater than the velocity of the filaments to reduce the extent of necking down of the filaments.

Abstract: A method for the production of a hydrophilic porous membrane of polyvinylidene fluoride excelling in perviousness to water and other various properties and enjoying high commercial value, having uniform hydrohilicity imparted to the surface of pores therein, which porous membrane is characterized by the fact that the reflection spectrum thereof in the visible zone is substantially unchanged from that which existed before the treatment for impartation of hydrophilcity. The method for the production of the hydrophilic porous membrane is characterized by chemically treating the porous membrane is a strong alkali solution containing an oxidizing agent.

Abstract: This invention relates to a process for combining a low melting binder fiber with a continuous filament base yarn to form a composite yarn having good bulk and a high level of interlace. More particularly, the process involves bulking a continuous filament yarn, combining it with the low-melting binder fiber, interlacing the combined yarn, and then fixing the interlace.