Abstract: Poly(p-phenyleneterephthalamide) yarn of improved fatigue resistance is prepared by spinning the polymer in sulfuric acid through an air gap into an aqueous coagulating bath to produce a coagulated yarn, maintaining the coagulating bath at a temperature of at least 20.degree. C., washing and neutralizing the yarn while it is under a tension of from 0.2 to 0.4 grams per denier, and drying the yarn at a temperature below 200.degree. C. while it is maintained under a tension of 0.05 to 0.2 grams per denier.

Abstract: A process for preparing a carbon fiber having an elliptical cross section, characterized by the steps of extruding spinnable pitch from a nozzle with an orifice rectangular or otherwise shaped in cross section and having a width/height ratio of more than 1, fully relaxing the molecules orientated by the nozzle on discharge from the nozzle, effecting continuous winding-up to obtain a pitch fiber elliptical in cross section, rendering the fiber infusible and carbonizing the same.

Abstract: A polyamide fiber excellent in strength, which comprises at least one of polycapramide, polyhexamethylene adipamide and polytetramethylene adipamide in an amount of not less than 60% by weight on the basis of the polyamide fiber and which is characterized by having a relative viscosity of not less than 2.3 and less than 3.5 (measured on a 96% by weight sulfuric acid solution having a polyamide concentration of 10 mg/ml at 20.degree. C.), an index of birefringence (.DELTA.n) (measured after 24 hours under the conditions of 30.degree. C. and 80% relative humidity) of not less than 55.times.10.sup.-3 and a tenacity of not less than 12.0 g/d. The method of preparing the noted polyamide fibers includes spinning of the polyamide to produce filaments, cooling the filaments, taking up the filaments to make an index of birefringence of 13.times.10.sup.-3 or less and drawing the filaments so taken up.

Abstract: A process for preparing pitch-type carbon fibers by melt-spinning a pitch-type material, rendering the material infusible and carbonizing it, characterized by the steps of passing molten pitch, before reaching the final nozzle, through a capillary portion of circular, otherwise shaped, or slit type to thereby apply a shearing stress at least 1/2 as high as the level of shearing stress to be exerted during the passage through the final nozzle orifice, maintaining the molten pitch in a state substantially free of shearing stress and then passing the pitch through the nozzle orifice for spinning.

Abstract: A nonwoven web is prepared by the method of forming a nonwoven web from a composition composed of at least one thermoplastic polymer and at least one defined siloxane-containing additive, which method involves the steps of (A) forming fibers by extruding a molten thermoplastic composition through a die; (B) drawing the fibers; (C) collecting the fibers on a moving foraminous surface as a web of entangled fibers; and (D) heating the web at a temperature of from about 27.degree. to about 95.degree. C. for a period of time sufficient to cause additional additive to move to the surfaces of the fibers. The method of the present invention is particularly useful for the preparation of nonwoven webs, the fibers of which have at least one surface characteristic which is different from the surface characteristics of the polymer component of the thermoplastsic composition.

Abstract: A method of preparing carbon filaments which comprises exposing a suitable thermostable substrate which is covered with reduced monocrystalline metal particles with a diameter of at least 5 nanometers to a carbon containing gas mixture at temperatures of about 250.degree. up to about 700.degree. C. to 800.degree. C., for a period of time sufficient to form filaments of the desired length, and thereafter removing the substrate and/or the metal particles. The filaments are characterized by a crystalline graphitic structure and a morphology defined by a fishbone-like arrangement of the graphite layers along the axis of the filaments. A high carbide content is a prerequisite for the nucleation of the filamentous carbon with a fishbone like structure.

Abstract: A method of producing continuous multifilament yarns of polyethylene terephthalate comprising the steps of extruding the polymer in the molten state, cooling the filaments by blowing, and application of dressing, interlacing and winding. The polymer viscosity is in the range of 0.52 to 0.82. The filaments, on exiting the die, meet a conduit which protects them against air streams. Winding is carried out at rates in the range of 3,500 to 5,500 meters/minute. The fiber yielded by the method has a modulus in the 300 to 500 cN/tex range, tenacity in the range of 30 to 40 cN/tex, ultimate elongation varying from 50% to 80%, and shrinkage in water of between 3% and 8%.

Abstract: Raw starch is slurried in an aqueous solution containing up to and above saturation levels of an ammonium sulfate, ammonium monobasic or dibasic phosphate, sodium sulfate or mixtures thereof. The slurry is then cooked at temperatures above about 150.degree. C. The resulting starch cook is then extruded using conventional methods into a coagulating salt bath thereby producing a starch fiber. When the starch is cooked in the presence of a salt prior to spinning in the coagulation bath, dilution of the salt in the coagulation bath is minimized, thus reducing the evaporation load.

Abstract: An improvement in a high speed process to produce high performance multi-end polyester yarn comprises extruding molten polyester from a spinnerette to form filaments, then cooling, lubricating and advancing the filaments to a forwarding roll system at the speed of from about 1000-4000 meters per minute so that a partially oriented yarn is produced, then feeding the filaments from the forwarding roll system to a first draw roll system to partially draw the yarn, then feeding the paritally drawn yarn to a second draw roll system having a draw point localizing device then feeding the filaments from the draw roll system to a conditioning roll system and finally taking up the filaments. The improvement is the use of matte finish on godet rolls having an arithmetic mean roll surface roughness value of from between about 35 microinches and about 120 microinches to feed and withdraw yarn to and from a draw point localizing device in the second draw roll system.

Abstract: In a method for manufacturing a sealing ring with a sealing lip, the material forming the sealing lip is fabricated in plastically deformable condition into the shape of a column-like hollow body. Prior to solidification, the column-like hollow body is twisted between axially spaced cross-sectional planes. This forms return elements with hydrodynamic action. Subsequently, the hollow body is solidfied and its diameter is enlarged axially outside the region of the sealing lip and it is then secured in a sealing ring housing.

Abstract: Filaments are produced from polymers having an inherent viscosity of at least 0.7 measured in concentrated sulfuric acid and containing in the polmer chain at least 50 percent of the repeating units. ##STR1## by melting the polymer and heating the melt to a temperature of from about 20.degree. C. to about 80.degree. C. above the melting point of the polymer, passing the melt through a filter pack having a filtering area of at least about 8 in.sup.2 and a total volume of at least about 1.2 in.sup.3 per pound of polymer extruded per hour, and containing inert, irregularly shaped particles having a mesh size of about 25 to 140 to provide a pressure drop at least about 800 psig., and extruding the melt through spinning openings of desired shape to form filaments. The process is capable of producing fibers and yarns having a dpf of about 15 to 100, a tenacity of about 1 to 2 grams per denier, an elongation at break of about 50 to 160 percent and a modulus of about 20 to 30 grams per denier.

Abstract: To produce non-woven materials, endless filaments in the form of a warp are drawn off a filament draw-off nozzle to which are joined a filament offlet, a filament guide tube and a spreading extruder. An amount of compressed air under high pressure is admitted to the filament draw-off nozzle. By means of the invention the amount of compressed air at the filament draw-off nozzle is reduced and at the same time an additional amount of compressed air under relatively low pressure is admitted between the filament guide tube and the spreading extruder by means of a propelling nozzle. In spite of an additional amount of compressed air at the propelling nozzle the reduction at the filament draw-off nozzle is so large that for the isothermal compression output as a whole a considerable savings in energy of almost 30% can be achieved, and this while maintaining the important filament draw-off force necessary for the drawing of the filaments inside the filament offlet.

Abstract: A process is provided for preparing high strength polymetaphenylene isophthalamide fibers by the steps which include extruding a dope solution of a metaphenylene isophthalamide polymer in an organic solvent through a spinneret and into a coagulating liquid form in undrawn polymer filament; adjusting the content of the organic solvent; carrying out a first wet drawing in at least one aqueous wet drawing bath; making a second adjustment of the content of the organic solvent; carrying out a second wet drawing at a specified draw ratio in at least one aqueous wet drawing bath; drying the second wet drawn filament; and dry drawing the dried filament.

Abstract: A process for producing a shaped article of polyamide which comprises (1) melt-shaping an intimate mixture of 100 parts by weight of a polyamide having hexamethylene terephthalamide as main recurring units and 20 to 500 parts by weight of an aromatic hydroxy compound, and then (2) removing the aromatic hydroxy compound from the resulting shaped article by extraction.

Abstract: A method of applying end stop members by injection molding to a slide fastener having rows of coupling elements on opposed stringer tape edges, a predetermined length of each of these tape edges being held upright or substantially vertical to the plane of the tape web and embraced by end stops molded in place with that predetermined length of tape edges maintaining alignment with its neighboring contiguous tape edge outside the molded end stop.

Abstract: Thread bundles which are transported from top to bottom, can be wetted with liquids by means of a device consisting of a system releasing the liquid, conduits and a storage container as well as suitable transporting means for the liquid, whereby the system releasing the liquid has at least two slotted nozzles positioned one above the other and opposite each other, having a horizontal slot and whereby rods are attached at the slot ends which, seen from above, form an angle with the slot of from 100 to 170.degree., preferably from 115 to 160.degree..

Abstract: Preparation of a novel polyester fiber, such as a poly(ethylene terephthalate) fiber, having at least one continuous groove wherein the surface of the groove is rougher than the surface outside the groove is accomplished through a drafting process involving surface hydrolysis. The fibers have improved cover, softness, and wetting characteristics.

Abstract: A method of molding oriented structural yarn/polymer matrix composite structural articles in which a preform of oriented yarn layers saturated with a resin is placed in a shape-defining mold, which is put in an enclosure, and subjected to heat and pressure to cure the resin, after which a cooling medium may be introduced. To enable the use of lightweight multi-part molds, and a mixture of pressure is distributed evenly, an internal liner is collapsed about the mold prior to curing. The process is extremely productive, and allows for accuracy and reproducibility through the use of real time temperature monitoring and closed loop feedback control.

Abstract: A process for the preparation of high-performance grade carbon fibers, which comprises attaching a fine powder of at least one member selected from oxides and carbides of silicon, aluminum, titanium, and boron to a precursor fiber bundle of as spun pitch fibers, subjecting the fiber bundle to an infusibilization treatment, and subjecting the fiber bundle to a carbonization treatment.

Abstract: Composition (M) having a base of a cellulose ester having formate groups, this composition being an anisotropic solution containing:(a) the cellulose ester;(b) formic acid;(c) at least one phosphoric acid.A process for obtaining this composition by dissolving the cellulose and a process for obtaining articles by transformation of this composition, and, for example, regenerating the cellulose of these articles. A cellulose fiber is provided in which a degree of substitution of the cellulose by formate groups is either at least equal to 2% or is zero or less than 2%.