Abstract: Asymmetric acrylic hollow fibers for use in separatory processes as a selective membrane. The fibers are highly permeable and exhibit a high degree of selectivity in discriminating mixtures into their various components. The fibers are formed by extruding an acrylic polymer solution through an annular orifice while simultaneously injecting a coagulating fluid into the bore of the fiber extrudate as it is formed. The extrusion may be directly into a coagulating bath maintained at a temperature of from 60.degree. to 80.degree. C. or alternatively the freshly extruded fiber may be first passed through an air space (evaporation zone) and thence into the coagulating bath. Following coagulation, the fibers are water washed to remove residual solvent.

Abstract: A porous polytetrafluoroethylene tubing, useful as artificial internal organs or industrial filtering materials for, for example reverse osmosis, ultrafilteration, etc., having a microporous fibrous structure in which the fibrous structure is composed of fibers and nodes connected with each other and the microporous fibrous structure differs between the outer surface portions of the tubing and the inner surface portions of the tubing, and a process for producing the porous resin tubing comprising heating a tubing made of an unsintered polytetrafluoroethylene under conditions in which the tube is stretched at least in the longitudinal direction of the tubing and such that the outer surface of the tubing is heated above about 327.degree. C and the inner surface of the tubing is heated to a temperature below the temperature of the outer surface.

Abstract: A composite article comprising at least two load-bearing members one within the other and having mutually contacting surfaces adapted to generate a restraining force resisting relative axial movement of the members, wherein the members are constructed such that a local reduction in said restraining force takes place as the local tensile stress in the article increases.

Abstract: Compositions are provided which employ a fibrous, cellular, absorbent organic material in place of asbestos fiber as a reinforcing and thickening additive; a wide variety of compositions including cements, sealants and paints can be made; a particularly preferred fibrous material is a foamed urea-formaldehyde crushed to a fibrous mass.

Abstract: Additives can be permanently incorporated into melt spun fibers by cold drawing the fibers under conditions that generate a network of interconnecting microvoids within the fiber. The microvoids are formed in the presence of specified liquid or vapor media which fill the microvoid network. The temperature of the medium is below the effective glass transition temperature of the fibers containing said medium. The additive is either present in said medium or is applied to drawn fibers containing said medium.

Abstract: There are disclosed porous polypropylene hollow filaments which have a surrounding wall portion of less than 60 .mu., preferably 40 .mu. in thickness which contains many fine holes communicating with each other, distribution curve of radius of said fine holes having at least one maximum points within the range of 200-1200 A. The method for producing said porous polypropylene hollow filaments is also disclosed.

Abstract: A method of manufacturing of a novel very fine seamless heat resistant synthetic resin tube having a wall thickness of not more than 0.3 mm, by applying a specific heat resistant synthetic resin varnish as defined in the specification on a metal wire and curing said resin varnish to form the synthetic resin layer on the metal wire, drawing the heat resistant synthetic resin coated wire above the yield point of the metal wire and separating the resulting synthetic resin tube from the metal wire.The method of the present invention may produce a composite heat resistant synthetic resin tube in which a plurality of the above-described tubes are made to adhere tightly parallel with each other in the longitudinal direction or a double layer resin tube, one layer of which is a thermally adhesive synthetic resin and the other layer of which is the heat resistant resin.

Abstract: A process for the combination of pneumacel fiber and synthetic elastomeric foam is provided that yields highly desirable, composite cushioning structures. A compressed, resin-bonded pneumacel batt is pre-expanded and combined with a precursor of an elastomeric foam under conditions leading to minor but definite penetration of the batt by the foam to give durably unitary cushioning with the best features of both materials.

Abstract: A suede-like or deer skin-like raised woven or knitted fabric having at least one raised surface is produced by providing a woven or knitted fabric using a yarn consisting of synthetic hollow composite fibers each composed of two or more fiber-forming polyester constituents and two or more fiber-forming polyamide constituents and having a hollow space surrounded by the polyamide and polyester constituents which are arranged alternately with each other and adhered to each other side-by-side so as to form a tube-shaped body, and raising a surface of the fabric while allowing the hollow composite fibers located in at least the raised surface portion of the fabric to be divided into numerous very fine fibrils consisting of said polyester and polyamide constituents.

Abstract: Hollow synthetic fibers useful in reverse osmosis, ultrafiltration, gas separation and the like, having high hydraulic permeability to the solvent and capable of operation at pressures from 600 psi and up, are prepared by forming a solution of a fiber-forming polymer in a suitable solvent, adding to the solution a second polymer soluble in the solvent but with limited compatibility with the first polymer when their total concentration increases on coagulation, extruding the resulting solution through an orifice equipped for coaxial extrusion so that coagulating fluid within tube flow results, precipitating with a liquid which is miscible with the solvent for the fiber-forming material, is a non-solvent for the first polymer and a solvent for the second, contacting the extruded solution with the precipitating liquid either coaxially through the extrusion device or by passing the extrudate through the precipitating liquid, and finally washing the resulting hollow fiber free of residual solvents and non-solvents

Abstract: Acid resistant glass fibers are prepared by treating the surface of a siliceous glass fiber with an aqueous acid solution to increase the silica content thereof. The aqueous acid solution is removed from the surface of the glass fibers and the fibers are heated to dehydrate or partially dehydrate the surface. The glass fibers as produced have a dual composition; the outer surface of the fiber is rich in silica in relation to the core of the fiber. The fibers so formed are highly resistant to acid attack.

Abstract: Novel glass fiber strands of relatively short lengths are disclosed in which the strands are formed of a consolidated bundle of glass filaments. The filaments making up the consolidated strand have external diameters of 0.0003 to 0.003 inch (0.0016 to 0.076 millimeters) and 10 to 65 percent of their volume is hollow. The filaments are further sealed at each of their ends in the short lengths of consolidated strand.

Abstract: Novel injection molding fiberglass reinforced thermoplastic concentrate granules are prepared by a process wherein continuous multifilament glass strands are impregnated with from 10 to 30 percent by weight of thermoplastic resin and, while the strand is maintained under controlled temperature conditions, the impregnated strand is cut to lengths of at least 1/8 of an inch.

Abstract: A dry-wet process for forming interiorally asymmetric hollow fiber cellulose acetate membranes is disclosed.

Abstract: A golf shaft and its method of fabrication. The shaft comprises a tapered, scrolled, oblong blank of thin laminated sheet material having alternating laminae of woven glass fabric and resin impregnated unidirectional graphite fibers. The fibers are arranged in a predetermined specific angle of orientation with respect to the longitudinal axis of the shaft.

Abstract: Multi-cavity filaments having improved resilience and anti-soiling properties have continuous cavities along their length with each cavity having a vertex angle formed by two sides or legs of the cavity of between about 65.degree. and 140.degree.. The vertex angle of each cavity points substantially toward the center axis of the filament. The cavities are spaced from each other and from the periphery of the filament in a manner producing a filament having good physical and aesthetic properties.

Abstract: Normally hydrophobic, polyethylene hollow fibers having contiguous microporosity are prepared by extruding a heated solution of a polyethylene and an ester from a hollow fiber spinnerette, simultaneously cooling and drawing the forming fibers to a ratio of up to 40 to 1, drawing the gelled fibers to an overall ratio of from about 1.5/1 to 800/1 and then removing the ester. The maximum pore radius ranges up to about 50A, and the fibers have gas permeabilities approaching 10.sup.-.sup.2 cc (STP) per cm.sup.2 per second per cm. Hg. transmembrane pressure differential. A significant increase in permeability over polyethylene hollow fibers made according to the teachings of the prior art is achieved.

Abstract: A beam and strut girder for use in vehicles and in other constructions which comprises a girder construction consisting of a fiber reinforced plastic material.

Abstract: A foam coated fiber core, the outer pores thereof being filled with substance of a solid, liquid of pressurized gaseous character in which the foamy coating acts as a carrier therefor, and in which the filler enhances the utility of the structure for many uses, such as uses of the fiber per se or as a carrier or dispenser of the added substance being carried therein.

Abstract: A flexible honeycomb structure formable into a non-planar contour comprising a cellular web of thin sheet material is disclosed. The cells in the web each have a cross section comprising three substantially congruent segments equally angularly disposed about a common center. Each such segment includes a non-linear portion intermediate to its ends, and is preferably in the shape of four contiguous sides of a hexagonal configuration for easy nesting of the cells. The present invention also provides alternate methods for forming the flexible honeycomb structure.

Abstract: The article used and the method of forming a support structure, such as an orthopedic cast, comprising interlacing one or more flexible, pliable filaments having a photopolymerizable material enclosed entirely within the interior of the filaments so as to form a pliable fabric article which can be readily conformed to the surface with which it is in contact and exposing the fabric article to a source of wave energy, such as ultra-violet light, which effects polymerization of the material within the filament and transforming the fabric into a rigid structure entirely by means of the mechanical interlock formed between the filaments; thereby forming a rigid support structure without the application of a malodorous, sticky or powdered stiffening or bonding agent to the outer surface of the filaments or fabric.

Abstract: Open structured, net-like composite filaments are disclosed and include two or more longitudinally extending wavy or undulating filaments which intersect one another at a plurality of points. The wavy or undulating filaments are joined to one another at least at a portion, preferably a majority or all, of their intersecting points to maintain the configuration of the individual filaments and to sustain the open structure of the composite filaments.

Abstract: A naturally crimped polyacrylonitrile fiber having an asymmetrical cross section, the cross section having at least two large oblong lobes, the angle between at least two of these lobes being less than 90.degree., the fiber having an outer structure which has a relatively high density and has a variable thickness, this outer structure enclosing an inner structure which is porous and less dense than the outer structure.The process for producing crimped polyacrylonitrile fibers comprises spinning a solution of a polyacrylonitrile polymer into a cold bath at a temperature of less than 30.degree.C.

Abstract: A method of forming hose construction utilizing an aromatic polyester thermoplastic core and reinforcing means mechanically bonded about the core with the core portion in which the reinforcing means is embedded being substantially free of stress. A sheath may be provided about the reinforcing means and may be autogenously bonded to "Hytrel", an aromatic polyester thermoplastic body of material coating the reinforcing means.

Abstract: Method for melt spinning from inelastic materials extruded lengths of predetermined cross-sections from predetermined arrangements in spinnerets of non-round orifices having one axis or no axis of symmetry in the plane of the spinneret face, and to such arrangements of two or more such spinning orifices in spinnerets for practice of the method by which non-axisymmetric emergence behavior, i.e., "kneeing," of inelastic fluid streams from spinnerets is utilized. Each non-round orifice in the arrangement has a significant kneeing potential of greater than (.+-.) 0.1, and preferably greater than (.+-.) 0.

Abstract: A method is provided for fabricating asymmetric acrylic hollow fibers for use in separatory processes as a selective membrane. The fibers are highly permeable and exhibit a high degree of selectivity in discriminating mixtures into their various components. The fibers are formed by extruding an acrylic polymer solution through an annular orifice while simultaneously injecting a coagulating fluid into the bore of the fiber extrudate as it is formed. The extrusion may be directly into a coagulating bath maintained at a temperature of from 60.degree. to 80.degree.C. or alternatively the freshly extruded fiber may be first passed through an air space (evaporation zone) and thence into the coagulating bath. Following coagulation, the fibers are water washed to remove residual solvent.

Abstract: This invention provides a tetrafluoroethylene polymer in a porous form which has an amorphous content exceeding about 5% and which has a micro-structure characterized by nodes interconnected by fibrils. The material has high porosity and high strength. It can be used to produce all kinds of shaped articles such as films, tubes, rods, and continuous filaments. Laminations can be employed and impregnation and bonding can readily be used to produce a large variety of articles. Compressed articles of very high strength can also be produced from these porous forms.

Abstract: Hollow semiconductor bodies having an outer surface composed of a doped semiconductor material and an inner surface composed of a pure semiconductor material are formed by sequential deposition from a gaseous thermally decomposable semiconductor compound onto a heated carrier member. The multi-layer hollow semiconductor bodies are directly heatable during diffusion of dopants into semiconductor elements.

Abstract: Filaments having a substantially increased inner surface, in particular porous filaments of filaments having a cracked, notched or nicked surface of thermoplsatic material are produced by subjecting filaments of thermoplastic material, preferably containing a pore-forming agent, to a heating medium at a temperature at least 100.degree., preferably 150.degree.C.

Abstract: A process for producing a hollow carbon or ion-exchange filament which comprises treating a filament consisting of a fiber-forming polymer of predominantly an uncured novolak resin composition with a curing reagent in the presence of a curing catalyst to effect the cure of the filament extending from the peripheral portion to the axial portion thereof to a depth of 20-90% of the cross-sectional area of the filament, removing the uncured core portion of the filament by extraction with a solvent, and then subjecting the resulting hollow novolak resin filament to a carbonization treatment or introducing an ion-exchangeable group into the resulting hollow novolak resin filament; and products produced by this process.

Abstract: Synthetic filaments having a dull appearance and a feel similar to that of natural fibers, as well as a process for making same, are disclosed. The filaments have an integral skin-core structure, with the core formed of oriented dense polymer and the skin formed of the same polymer, in a fibrous and vesicular form. The filaments are produced by spinning the filaments and quenching the filaments while in the molten state in an inert cooling medium having a temperature of less than 100.degree.C. The inert cooling medium is a swelling agent for the polymer at temperatures above the polymer solidification point and a non-swelling agent for the polymer at temperatures less than 100.degree.C, the degree of swelling progressively decreasing with the decrease of the polymer filament temperature from the polymer solidification temperature to the temperature of the cooling medium.

Abstract: Hollow membrane fibers are formed from a mixture of N-alkoxyalkyl polyamide, polyvinyl alcohol, di(lower alkyl) sulfoxide and water. The fibers are useful for separating chemicals, e.g., aliphatically-unsaturated hydrocarbons, from mixtures containing them.

Abstract: Generally linear foamable strandular particles which are asymmetrical about a plane generally containing the longitudinal axis provide a desired curled dunnage material when heated to cause foaming. A wide variety of methods may be used to introduce the desired asymmetry.

Abstract: Pen nibs are made by extruding rods from fused thermoplastic material, with a cavity in the rod of star-shaped cross-sectional configuration. The extruded rod is then cooled and mechanically drawn to reduce its diameter about 50%, which closes the inner ends of the arms of the star and brings them together at the center of the rod, while leaving the outer ends of the arms relatively large. The resulting product is then sharpened at both ends for use as a pen nib.