Abstract: The present invention relates to an acrylic fiber having excellent water absorbency. The fiber has a porous core and a relatively dense skin structure. It is a blended polymer which comprises an acrylic polymer copolymerized with a synthetic polymer which is miscible but substantially incompatible therewith, and is soluble in a solvent for the acrylic polymer but is insoluble in water.

Abstract: A compound composite structure is a combination of plastics and other materials forming a structure usable in the fabrication of manufactured products or components. A compound composite structure is composed of a thermoplastic resin material bonded to, by mixture with, a composite reinforcing structure. The composite reinforcing structure consists of fibers imbedded in a thermoplastic resin material. The composite reinforcing structure may be formed by passing extruded plastic resin material through a die which imbeds fibers. The compound composite structure may be formed by mounting a preformed composite reinforcing structure in a molding die and by injecting thermoplastic resin material into the molding die.

Abstract: An article which has utility as a surface covering for materials such as resilient flooring, furniture, walls, ceilings, counter tops and the like is produced by aligning and embedding a plurality of hollow fibers or metallic fibers on or near the surface of a translucent medium. The article is typically in the form of a film, sheet, or board.

Abstract: A new and useful hydrophilic polyester fiber and process of making same are disclosed; the fiber has a stable pore system exhibiting a moisture pickup (regain) of at least about 2 percent by weight at 40.degree. C. and a relative humidity of 92%. Our experiments indicate that the proportion of moisture regain is attributable to capillary condensation in an amount of at least 25%. The hydrophilic properties are the result of a certain pore system within the fiber which enables capilliary condensation to occur significantly. The invention describes one way to accomplish this, namely by the addition of a predetermined amount of a suitable oxalato-complex to a suitable polyester mass. Most preferably, about 10% by weight K.sub.3 Al(C.sub.2 O.sub.4).sub.3 is added to the polyester mass.

Abstract: Thin walled tubing formed of a melt spinnable synthetic polymer having a flow-through cross-section amounting to 30 to 95% of the total tubular cross-section and a breaking elongation of less than 100% prepared by melt spinning a synthetic polymer so as to form a tube and then drawing off the tube thus formed at a velocity which is greater than 3500 m/min. Preferably the process is carried out under utilization of the phenomena of natural fiber bending whereby the distance between the spinning means and the take-off means can be decreased.

Abstract: A filament of synthetic polymers which, in its cross section over the entire length of the thread, comprises at least three layers, of which at least two layers are electrically conductive and at least one layer located between the conductive layers consists of an electrically insulating synthetic polymer.

Abstract: Textile-quality multifilament yarns that are highly sorptive for organic vapors, mists and solutes are described. Each filament comprises a microporous polymeric sheath filled with a core of sorptive material. In a multifilament spinneret having a hollow needle in each orifice, a slurry containing the sorptive material is supplied to each needle, and a blend of a polymeric material and a pore-forming material is supplied to the orifice externally of the needle. The spun composite fibers are drawn and subsequently extracted to porosify the sheath and to activate the sorptive property of the cores.

Abstract: A monolobal acrylonitrile polymer fiber is disclosed in which a continuous hollow extends throughout the fiber length, which hollow is surrounded completely by a solid polymer composition substantially devoid of sheathcore structure, density gradient, and void structure, said fiber being less than about 50 deniers per filament and having desirable textile properties.

Abstract: The present invention provides a process for preparing microporous hollow fibers by solvent stretching a non-porous hollow precursor fiber having a controlled degree of molecular orientation as measured by birefringence. Control of the precursor fiber orientation, yields a microporous hollow fiber having an improved balance of mechanical strength and permeability.

Abstract: The present invention relates to FRP members, the apparatus and process for making same. The FRP members are reinforced with helical strands of reinforcing material disposed in expanded helices of opposite hand, the helices of each hand being contained in discrete layers. The lead angle of each helix may be constant or varied along the length of the member independently of whether the member is cylindrical or tapered in order to provide the desired structural characteristics. The process comprises impregnating the reinforcing strands with resin and wrapping those strands onto a mandrel by apparatus in which relative rotational as well as relative translatory movement between the mandrel and a winding head may be effected to wrap the strands onto the mandrel. At least one relative movement may be selectively varied to effect the desired lead angle to the helically disposed reinforcing strands along the length of the mandrel.

Abstract: A device for arresting the growth of a rip in reinforced flexible sheet material, for example elastomeric sheet material reinforced with woven nylon fabric, comprises a flexible sheath member having a flexible core member extending throughout its length and chemically bonded thereto. The sheath member includes tensile load path discontinuities at intervals along the length of the core member and at least in regions of the sheath member remote from the core member. The tensile load path discontinuities prevent tensile loads being transmitted along the length of those regions of the sheath member which are not bonded to the core member, such loads being diffused into the core member because of the bond between the sheath member and the core member. A number of these devices may be attached to an air cushion vehicle flexible skirt assembly manufactured from sheet rubber reinforced with woven nylon fabric so as to arrest the growth of rips which may propagate during operation of the vehicle.

Abstract: Permselective membranes are provided consisting of lactam-polyol-polyacyl lactam block terpolymers having from 35 to 75% by weight polylactam blocks and 25 to 65% by weight polyalkylene ether blocks. The membranes are particularly suitable as blood dialysis membranes having improved permeability to solutes in the medium range of molecular weights while maintaining acceptable ultrafiltration rates and permeability to low molecular weight solutes. The membranes are provided both as planar films and hollow fibers, have high hydrolytic stability under hot wet sterilization conditions and good mechanical properties under hemodialysis conditions.

Abstract: A moldable article useful for making a form-stable article is described. The moldable article comprises a formable material that is a moldable polymeric or prepolymeric substance that can be cured to a form stable state and a curing agent, in close proximity to the curable substance but isolated therefrom, in frangible hollow fibers. In use, the frangible hollow fibers are ruptured to release the curing agent and the moldable article, in a first configuration, can be shaped to a second configuration in which it is maintained until the formable material is cured sufficiently for it to be form-stable in the second configuration. The moldable article can be used to make molds, casts, support for a portion of the human or animal anatomy, or other articles with diverse utilities.

Abstract: Dry-spun hydrophilic core-jacket filaments and fibres of polycarbonates having a porosity and a water retention capacity of at least 10%, a mercury density of less than 1.0 g/cc, a strength of at least 1.5 cN/dtex and a second order transition temperature of at least 125.degree. C. and a method for producing said filament and fibres by a dry-spinning process, wherein, immediately on leaving the spinnerette but before solidifying, the filaments are brought into contact with steam.

Abstract: A low cost, high tolerance molded coil is disclosed together with a method of constructing the same. A wound coil is provided with connection leads. A mold having a mold cavity therein for the formation of an integral outer core and for supporting the coil is provided. The mold also produces integral securing portions for securing the coil to the outer core. The wound coil is placed in the mold cavity and a pre-molded and pre-shrunk plastic inner core is positioned inside of the coil substantially along the coil's longitudinal center line. A heated molding plastic is injected into the mold cavity so as to form the integral outer core for supporting the coil and securing portions of the coil. The molded coil is cooled and removed from the mold without withdrawing the inner core from the molded coil, which thereafter remains in the finished product. By use of the pre-molded and pre-shrunk plastic inner core, shrinkage and other deformations of the outer core is prevented.

Abstract: Polyimide fibers which have a porous, microcellular structure. Methods of making such fibers from a precursor under conditions which cause the precursor to foam and undergo imidization.

Abstract: A process for producing a synthetic rush-like structure which comprises causing an acrylonitrile polymer composition in a substantially melted state (Polymer A or B or C) to flow down towards a spinning orifice; adjusting the pressure of the system in which the melt just before the orifice is present to within a specific range; extruding the melt to form a foamed product; and subjecting the foamed extrudate to heat treatment, thereby obtaining a synthetic rush-like structure resembling the natural rush plant in outer skin structure and internal structure and having excellent sensory and practical properties.

Abstract: A bitumen composition modified with an organo silane in which a bitumen such as asphalt is reacted with an organo silane containing ethylenic unsaturation or an organo silane containing at least one hydrogen atom bonded to the silicon atom whereby the organo silanes react with ethylenic unsaturation of the bitumen to chemically bond the organo silane to the bitumen. Also included are bitumens which have been chemically modified by reaction with steam, air, ammonia or aliphatic amines which have been reacted with a silane containing a functional group reactive with the bitumen. Bitumen compositions of the invention are preferably used in the treatment of glass fibers for use as reinforcement in asphalt systems.

Abstract: The invention relates to a process for the production of hygroscopic filaments or fibers by dry-spinning a polymer solution wherein immediately they issue from the spinning jet or at the latest at a time when their solidification is still not complete, the filaments are brought into contact with water-vapour or with the vapour of another liquid which coagulates filaments.

Abstract: A microporous filler for dental composite resin restorations has been developed which gives greatly improved finishability, system non-toxicity and x-ray opacification. These fillers are prepared from frits obtained by the low temperature calcination of gelled inorganic "polymers" followed by a pulsed high-heat treatment.

Abstract: In blood dialyzers in which hollow fibers are potted in plastic tube sheets and the tube sheets are then cut to form a manifold surface providing access to the interior of the hollow fibers, blood clotting at the manifold surface is greatly reduced by treating the surface to increase the radii of the microscopic sharp edges of the fiber ends which are produced by the cutting process. The smoothing of the fiber ends can be accomplished by momentary heating, flame polishing, etching, or coating of the manifold surface with a varnish.

Abstract: A vascular prosthesis comprising a tubing of porous polytetrafluoroethylene, the polytetrafluoroethylene tubing having a fibrous structure of nodes and fibers connecting the nodes together and having a structure in which the fibrous structure at the inside surface of the tubing is finer than the fibrous structure at the outside surface of the tubing.

Abstract: Cellular linear filaments are disclosed and include a substantially continuous, integral plastic hollow member having internal generally transverse partitions which divide the hollow member into cells. The wall of the hollow member can be continuous or can contain orifices, slits, windows and the like. The cells can be open or closed and uniformly or randomly spaced along the tubular member. The cells are defined by transverse partitions which can be integrally formed with the hollow member or they can be seals in the hollow member. Woven, non-woven and tufted materials including yarns made up in part or in total of the cellular linear element are also disclosed. The cellular linear element can be cut into discrete lengths to form pile-like elements which can be attached upright to a base to form a multi-element device.

Abstract: The invention relates to a process for the production of hydrophilic filaments and fibers which comprises wet- or dry-spinning a fibre-forming synthetic polymer from a spinning solvent containing from 5 to 50% of a substance which has a higher melting or boiling point than the spinning solvent which is miscible with the spinning solvent and with a liquid suitable for use as a washing liquid and which is a non-solvent for the polymer to be spun and from 0,1 to 20% by weight of at least one substance which decomposes into a gas under heating.

Abstract: The wearing comfort of textiles produced from synthetic fibers which are normally hydrophobic, e.g., polyacrylonitrile, is improved by modifications in the spinning process whereby hygroscopic fibers having a sheath/core structure and a microporous core are obtained, which fibers are capable of absorbing considerably more water than conventionally dry spun fibers of the same synthetic polymer not having a sheath/core structure. Several suitable dry spinning processes for producing the improved fibers are disclosed.

Abstract: Essentially inorganic monolithic hollow fibers having a radially anisotropic internal void volume wall structure. Process for the production of such fibers. Apparatus and processes using such fibers.

Abstract: A tubular composite structure for transmitting forces comprises a metal tubular core, preferably of aluminum, having a layer of structural metal adhesive on the exterior surface of the core. On top of the structural adhesive layer are alternating laminae of resin impregnated unidirectional reinforcing fibers, particularly carbon or graphite fibers, and of woven fiberglass, beginning with a layer of woven fiberglass followed by a lamina of resin impregnated continuous unidirectional reinforcing fibers and continuing in alternating fashion but ending with a final layer of resin impregnated continuous unidirectional reinforcing fibers, each successive layer of resin impregnated continuous unidirectional fibers having the fibers oriented at an angle of between about 5.degree. to 12.degree. with respect to the longitudinal axis of the metal tube and in opposite orientation with respect to the next preceding layer. The fibers in the woven fiberglass layer are oriented at 0.degree. and 90.degree.

Abstract: This invention is directed to a novel fiberglass pole construction and the method for forming such. The pole is of composite construction and includes inner, outer and intermediate layers resin bonded together into an integral hollow elongated tapered form exhibiting lightweight and high strength characteristics. The intermediate layer includes individual sublayers in turn formed from a plurality of strips of non-woven, unidirectional glass fiber fabric. The strips of each sublayer are circumferentially staggered about the periphery of the pole and are disposed lengthwise therealong so that the orientation of the glass fibers forming such strips is parallel to the longitudinal axis of the pole. Several such sublayers are built up until the necessary strength characteristics have been imparted to the pole. An outer layer of generally spirally wrapped ribbon essentially completes the structure.

Abstract: A fixing roller which is constructed by bonding in layers a heat resistant adhesive layer, a heat and oil resistant layer, a heat and oil resistant adhesive layer and an offset preventing layer to a core, wherein the offset preventing layer is formed before the solvent of the heat and oil resistant adhesive layer has been completely evaporated, and at least one component material of the heat and oil resistant adhesive layer is of a kind similar to the component materials of both the heat and oil resistant elastic layer and the offset preventing layer so that the peeling off of the offset preventing layer is obviated.

Abstract: A novel tubular composite structure for transmitting substantial forces comprising a metal tubular core having a layer of structural metal adhesive on the exterior thereof. On top of the structural adhesive layer are alternating laminae of resin impregnated unidirectional reinforcing fibers and of woven fiberglass, beginning with a layer of woven fiberglass followed by a lamina of resin impregnated unidirectional reinforcing fibers and continuing in alternating fashion but ending with a final layer of resin impregnated continuous unidirectional reinforcing fibers. All fibers are disposed at a predetermined angle of orientation with respect to the longitudinal axis of the tube. The number of layers disposed along the length of the tubular core varies such that the core thickness along the length of the tubular shaft has its greatest thickness at the mid section of the shaft.

Abstract: A crimped, high-strength regenerated cellulose yarn of filaments having a broken skin-core cross-sectional structure of which the skin comprises at least about 20 up to about 40% of the cross-sectional area, the peripheral skin surface is substantially smooth and the core section is "blown-out;" and a method of preparing the yarn from a specified viscose and spinning bath wherein the formed yarn is highly stretched and then crimped in the relaxed state in a plasticizing medium.

Abstract: A carbon graphite fiber reinforced shaft incorporating longitudinal plies and radial plies. In transverse aspect, the radial plies incorporate two interleaved helices with three turns around the shaft. The fibers in the two helices are oppositely oriented at an angle to the longitudinal axis of the shaft. The fibers in one radial ply have a modulus that is substantially 50% greater than the modulus of the opposed interleaved radial ply.

Abstract: A finishing welt, comprised of a reinforcing polyethylene rod surrounded by a fabric scrim and an outer encasing layer of polyvinyl chloride, is formed in an extrusion-embossment method and apparatus.The method includes feeding a composite preform, consisting of the polyethylene rod and the scrim, first through an essentially key-hole shaped passageway in a core pin of an extruder crosshead and then into a chamber within the crosshead where plastic material under pressure flows onto the preform. Immediately thereafter, the preform is conveyed through an essentially key-hole shaped orifice, where the welt is formed by extrusion. Next, the opposed sides of the welt are sequentially embossed as the welt is conveyed over external peripheral embossing surfaces of two spaced rollers.The resultant welt is essentially key-hole shaped in cross-section, with the scrim surrounding the rod within the enlarged head portion of the welt and extending into the smaller depending flange portion.

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: 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: 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: Polymeric sheets having on one or both sides a fabric texture and a network of elongated channels in the interior of the structural framework of the sheet. In one embodiment, the sheets comprise a plurality of interbonded continuous polymeric ribs extending in a direction parallel to the plane of the sheet. The ribs impart a fabric texture to both sides of the sheet and define between them recessed portions on each surface of the sheet. The elongated channels extend throughout the ribs. The open area between the ribs can vary from zero to 60%. In another embodiment, the sheets have an ultra-thin, pinhole-free silicone rubber membrane on one side and a fabric texture on the other side. The sheets are useful as burn coverings where they serve as synthetic temporary replacements for damaged or missing skin.

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: A process for the production of a multifilament textured yarn by melt-spinning different polymers (for example a polyamide and a polyester) or copolymers (for example copolymers of nylon-6 and nylon-6,6) to form a highly preoriented multifilament yarn at substantially the same draw-off rate for all the constituent filaments of the yarn, followed by stretching under substantially the same stretching conditions for all the constituent filaments of the yarn, the stretching ratio lying above the elastic limit of at least one of the spun polymers and the preorientation of the freshly spun filaments being sufficient to provide a maximum stretching ratio available in the stretching stage of not more than 1:2.5, i.e. not more than 2.5 times the unstretched or spun length of filaments. Yarns are produced which may have the appearance of texturized continuous multifilament yarns or crimped staple fiber yarns.

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: Substantially single-phase compositions which are substantially partial or complete hydrates of an acrylonitrile polymer containing at least 40% acrylonitrile units can be shaped into filaments and films. The nitrile groups of the polymer are hydrated to a selected extent depending on the particular polymer used. Hydration occurs only within a certain elevated temperature range and under at least autogenous pressure. Also disclosed are films and filaments having novel structural features which are spun from the substantially single-phase compositions comprising polymers or copolymers of 80% or more acrylonitrile. The filaments are characterized by a sheath which has a density gradient in which the density increases toward the surface and, after drawing, by a unique luster source ratio related to reflective interfaces. Many of the filaments have surface striations and an optically microvoided core. The filaments contribute good hand and good water absorption properties to fabrics made therefrom.

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: 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.