Abstract: A method for forming a substantially continuous filament of a thermoplastic work material and for imparting a swirling motion thereto comprises a body member which has a work material supply passage and a gas supply passage formed therein. An outlet nozzle section connects to the body member and has a substantially conically tapered shape. The nozzle section has a nozzle extrusion passage formed therein in communication with the work material supply passage. A housing member operably connects to the body member to delimit a substantially annular gas transfer zone in fluid communication with the gas supply passage and to delimit a substantially annular gas outlet passage around the nozzle section. The housing member includes an exit section having inner wall surfaces which substantially parallel the conically tapered shape of the nozzle section. The inner wall surfaces are in a selected spaced relation from the nozzle section to define the gas outlet passage.

Abstract: A method for splitting the flow of a spin solution in a standard flash spinning process to increase sheet uniformity at increased flow rates. In one embodiment, the apparatus comprises a coarse mesh screen that is positioned within the pressure let-down zone of the spinneret assembly. The screen divides the solution flow into numerous individual sheet uniformity compared to sheets formed without the screen and at the same flow rate. The method produces nonwoven sheets having less ropiness and improved uniformity at relatively high solution flow rates.

Abstract: A method comprising melting a mixture of at least one thermoplastic polyolefin and at least one additive having the general formula, ##STR1## and extruding the resulting melt through a die at a shear rate of from about 50 to about 30,000 sec.sup.-1 and a throughput of no more than about 5.4 kg/cm/hour, in which:(A) R.sub.1 -R.sub.7 are independently selected monovalent C.sub.1 -C.sub.3 alkyl groups;(B) R.sub.8 is hydrogen or a monovalent C.sub.1 -C.sub.3 alkyl group;(C) m represents an integer of from 0 to about 5(D) n represents an integer of from 3 to about 8;(E) the additive has a molecular weight of from about 350 to about 700;(F) the additive has a polydispersity of from about 1.0 to about 1.3; and(G) the additive is present in an amount of from about 0.5 to about 1.

Abstract: A carbon/carbon composites is produced by impregnating a tow of carbon filaments with a carbonaceous pitch, placing the impregnated tow in an open container, then subjecting it to a heat treatment under hot isostatic pressing.

Abstract: Colored, high strength, high modulus p-aramid fibers are prepared by including an organic pigment which is soluble in but not degraded by concentrated sulfuric acid in a p-aramid spinning dope wherein the solvent is concentrated sulfuric acid and spinning the pigment containing dope through an air gap into a coagulation bath and washing and drying the resulting fibers. The dissolved pigment is precipitated by the coagulation bath as particles with a diameter of less than 0.50 microns.

Abstract: An improved packaging material wherein a block, sheet or molded packaging material formed of molded expanded polystyrene is compressed under controlled conditions to increase the density of the packaging material and thereby increasing the deflection qualities and resiliency of the material.

Abstract: A process for the preparation of a polyimide molded form comprising the steps of swelling a primary-molded form consisting essentially of polyimide having recurring units of the formula (I) ##STR1## by using an aprotic polar solvent and subsequently stretching the swelled form.

Abstract: A process for preparing an injection-molded article having a three-dimensional pattern on a surface thereof includes placing a master film of a thermoplastic resin having a three-dimensional master pattern formed on a region thereof into a mold such that the master pattern is exposed to the mold cavity. An injection-moldable resin is then injected into the mold cavity so as to cause a surface region of the resin to conform to the three-dimensional master pattern on the master film, and to thereby transfer the master pattern onto said surface region of the resin. The master film is then removed from the surface region of the injection molded resin to thereby expose said three-dimensional pattern formed thereupon. Preferably the master film is formed of a thermoplastic resin having a melting point greater than the injection molding temperature. Other lower melting point thermoplastic films can be used by metallizing the film's surface so that it withstands the injection molding temperature.

Abstract: An injection molding method uses motors to effect measuring and kneading of a material to be molded and injection driving. The amount of movement of a rotary shaft or rectilinearly moving means connected to a screw is detected by a sensor, and the driving of the volume measuring motor and the injection motor is effected by the output of the sensor.

Abstract: Fine polyethylene terephthalate fiber having a monofilament denier of not more than about 4 deniers is spun at a high spinning speed of not less than 7,000 m/min, the polyethylene terephthalate filaments extruded from a spinneret having a plurality of spinning holes being passed through a heating zone provided beneath the spinneret and then being bundled by a bundling guide positioned beneath the point of completion of filament fining, which point exists within or below the heating zone. The obtained fiber has a highly improved dyeability.

Abstract: Process for producing producer-colored nylon fibers which are stain-resistant to acid dyes are made by adding pigment to nylon copolymers containing 0.25-4.0 percent by weight of an aromatic sulfonate or an alkali metal salt thereof.

Abstract: Polyolefin/polyester composite fibers having a low apparent Young's modulus and a filter element using the composite fibers are produced by subjecting a polyolefin as sheath component and a polyester as core component to composite spinning, stretching the resulting unstretched filaments to twice or more the original length at a temperature higher than the secondary transition point of the polyester by 20.degree. C. or higher and lower than the melting point of the polyolefin and annealing the stretched filaments at the above-mentioned temperature for 30 seconds or more, and having an apparent Young's modulus of 210 Kg/cm.sup.2 or less, and by winding up the above composite fibers on a core while heating the composite fibers to the melt-adhesion temperature of the sheath component, adjusting the void content to a desired one, followed by cooling and taking out the core.

Abstract: A pre-oriented molded article of ultrahigh-molecular-weight polyethylene is composed of ultrahigh-molecular-weight polyethylene having an intrinsic viscosity of at least 5 dl/g, has a degree of orientation of at least 0.8, and has such a creep property that a stretched product of the molded article having a degree of orientation of about 0.97 shows an elongation of not more than 2% in an atmosphere at 80.degree. C. at 1000 seconds. The pre-oriented molded article is produced by (1) extruding a high-concentration molding solution composed of 15 to 80 parts by weight of ultrahigh-molecular-weight polyethylene and 85 to 20 parts by weight of a solvent capable of dissolving said polyethylene from a molding die at a temperature at which the molding solution remains a solution, (2) taking up the extrudate at a draft ratio of at least 3, and cooling the extrudate during or after take-up to crystallize the polyethylene in the extrudate and to form a pre-oriented molded article.

Abstract: Fibers formed of a blend of metal oxide, such as titanium or zirconium oxide, with etheric phosphazene are formed by preparing solutions of etheric phosphazene and inorganic alkoxides, such as titanium isopropoxide. The solutions are then formed into fibers and cured at room temperature or with moderate heating. Fibers produced can be extensible, tough, hard, flexible, or brittle. They are multicomponent blends of the titaninum or zirconium oxide and phosphazene. The composite may be doped with low lattice energy salts to form conductive fibers.

Abstract: A process for producing a nylon 6,6 and polypropylene fiber wherein deposits of polypropylene on the yarn guide surface are substantially eliminated by adding nylon 6.

Abstract: A process for forming mixtures of short fibers of varying lengths, diameters and aspect ratios composed of an anisotropic polymer.

Abstract: A process for fabricating a composite in the form of a network of microfibrils which includes interpenetrating the microfibrils with a matrix material to form a composite which includes two continuous interpenetrating phases, a matrix-material phase and a microfibrillar-reinforcing-network phase.

Abstract: An improved process for manufacturing highly uniform industrial yarn which exhibits high tenacity, high modulus and very low shrinkage which comprises melt spinning polyethylene terephthalate into spun filaments and subsequently drawing the spun filaments in a heated zone to a draw ratio of at least about 1.05:1; wherein the spun filaments have a birefringence of at least about 0.075 and a crystallinity of at least about 10%; wherein the spun filaments are in the heated zone for a residence time of at least 0.3 seconds; and wherein the yarn in the heated zone is at a temperature which is between the glass transition temperature and the melting temperature of the polyethylene terephthalate.

Abstract: A method for the manufacture of a hollow fiber membrane by mixing polypropylene, an organic filler capable of uniformly dispersing in the polypropylene in a fused state and easily dissolving in an extractant being used, and a crystal seed forming agent. The resulting mixture, in a molten state, is discharged in the shape of a hollow fiber through an annular spinning nozzle and into contact with a liquid made of said organic filler or a compound similar thereto. This results in cooling and solidifying the hollow fiber, which is then forwarded into contact with an extractant incapable of dissolving polypropylene, to remove the organic filler and form the membrane.

Abstract: A method is disclosed for controlling the interfacial level of solvent vapor and overhead gas in a vessel. The solvent vapor level is controlled by means of a displacement body which is suspended from a load cell. The displacement body is partially immersed in the solvent vapor with the remainder being immersed in the overhead gas covering the solvent vapor. The displacement body's apparent weight is measured by the load cell and used to control the rate of solvent vapor removal from the spin-cell thereby maintaining the solvent vapor/overhead gas interface in the spin-cell at a desired level.