Abstract: The invention relates to a process for preparing wet- or dry-spun filaments and fibers of polymers which consist to more than 50% by weight of acrylonitrile units and which are continually treated with an aqueous solution containing copper(I) ions during the fiber production process but before a first heat treatment above 100.degree. C. and the copper content in the fibrous material is fixed by heating to above 60.degree. C., preferably to above 100.degree. C. The filaments and fibers thus obtained can be dyed with acid dyestuffs, have bactericidal properties, and can be subjected to accelerated pre-oxidation.

Abstract: Dry-spun synthetic fibers and filaments having an individual as-spun denier of 3 dtex are obtained by dry spinning a viscosity-stable spinning solution with a draft of at least 20.

Abstract: Porous acrylic synthetic fibers having water absorption property and having substantially no microvoids but having mainly macrovoids are produced by spinning an organic solvent solution containing 15.about.35% by weight of a polymer consisting of 2.about.30 parts by weight of cellulose acetate and 70.about.98 parts by weight of an acrylic polymer into a coagulation bath at a temperature of no higher than 30.degree. C., primarily drawing the spun fibers at a draw ratio of 2.5.about.8.0 times to form water swelled fibers wherein macrovoids are distributed, drying the water swelled fibers at a temperature of 100.degree..about.180.degree. C. to a water content of no greater than 1.0% by weight and secondarily drawing the dried fibers under wet heat to elongate the macrovoid structure.This invention includes acrylic composite fibers having water absorption property wherein at least one of components A and B consisting of 2.about.50% by weight of cellulose acetate and 50.about.

Abstract: An improved process for the thermal stabilization of an acrylic fibrous material or film is provided. A tetrasubstituted phosphonium salt which is capable of promoting the thermal stabilization is incorporated in a solution of the acrylic polymer prior to extruding the same to form a fibrous material or film, and the acrylic fibrous material or film having the tetrasubstituted phosphonium salt incorporated therein is heated in an oxygen-containing atmosphere until a thermally stabilized fibrous material or film is formed which is black in appearance, non-burning when subjected to an ordinary match flame and which is capable of undergoing carbonization. The presence of the tetrasubstituted phosphonium salt has been found to cause the thermal stabilization reaction to proceed at an accelerated rate.

Abstract: Flame resistant moulded halogen-containing polymer articles which contain antimony oxide are advantageously obtained by adding a soluble antimony compound which gives rise to an antimony oxide to the solution of halogen-containing polymer in an organic solvent, producing the moulded polymer article from the polymer solution and converting the antimony compound to antimony oxide in this article before or during the after-treatment.

Abstract: The present invention provides a process for producing acrylic fibers having excellent surface smoothness and a color development ratio not less than 105%, without generating numerous wrinkles peculiar to wet spinning. The process comprises wet-spinning an acrylonitrile polymer spinning solution of from 50.degree. to 70.degree. C. having a viscosity of from 40 to 200 poises at 30.degree. C., (a) with a spinning draft of from 0.05 to 0.2 in the case wherein the spinnerette orifice capillary length is 0.5 mm or less, and (b) with a spinning draft of from 0.13 to 2.0 in the case where the spinnerette orifice capillary length exceeds 0.5 mm; coagulating and water-washing the resulting fibers substantially without stretching; and thereafter wet-heat-stretching the fibers not less than 4 times in length at a temperature not lower than 80.degree. C.

Abstract: Acrylic fibers consisting of not more than 90 weight % of an acrylonitrile polymer and less than 10 weight % of a water-absorbing resin having a particular cross-linking density, particle diameter and degree of water-swellability, which are excellent in practical properties such as strength, elongation, color fastness, spinnability and water-absorption.

Abstract: Shapeforming acrylonitrile polymer film by providing acrylonitrile polymer aquagel film, conforming said aquagel film into the desired shape and while in said shape, heat-removing at least substantially all of the water from said aquagel film.

Abstract: A system for producing a biaxially oriented polymer film of predetermined gauge profile. Methods and apparatus are provided for forming a continuous film of the polymer having substantially uniform gauge by controlling the character of the film in its aquagel form prior to transverse stretching.

Abstract: The invention relates to a process for the continuous production of synthetic non-discolored filaments and fibers from a filament forming synthetic polymer being difficultly soluble in an organic polar solvent particularly polyacrylonitrile polymers which process comprises preparing a suspension of said polymer and said solvent at room temperature and subsequently heating the suspension thus formed for at least 3 minutes to at least 130.degree. C., and filtering the clear spinning solution formed without intermediate cooling, homogenizing and spinning it immediately afterwards into filaments.

Abstract: By adjusting the viscosity of the spinning solution, low molecular weight polymers of acrylonitrile can be spun to provide useful fiber having an unexpected higher dye color yield than fiber prepared from the corresponding polymer of higher molecular weight.

Abstract: Acrylonitrile polymer film is treated with non-volatile water-miscible glycol plasticizer to improve toughness and other film properties. In a unique, continuous, steady state process polyacrylonitrile aquagel strip is treated with plasticizer additive in concentrated aqueous solution. Aquagel strip is passed at substantially constant rate through a solution treatment bath. The aquagel strip, which may contain at least about 40 weight % water uniformly dispersed in the polyacrylonitrile, is contacted with the aqueous solution during a predetermined residence time in the bath. After passing the treated aquagel strip from the bath, excess aqueous additive solution is removed. The plasticizer additive can be metered to the aqueous solution at concentration greater than the aqueous additive solution of the bath at a rate substantially proportionate to desired steady state uptake of additive for the aquagel strip.

Abstract: A process for producing hollow acrylonitrilic separation membranes in fibrous form which comprises shaping a membranous product in hollow fibrous form from a solution of acrylonitrile polymer dissolved in formamide-containing dimethylformamide while maintaining the temperature of said polymer solution within a specified range and subjecting said membranous product to a solvent removal treatment under a specific condition, thereby producing an acrylonitrilic separation membrane which is asymmetric, porous in structure, and excellent both in separation ability and in mechanical strength.

Abstract: New polymer solutions, processes for producing such solutions, shaped articles made from these solutions, and process of making such articles, are disclosed. The polymer solutions contain cellulose having a degree of polymerization of at least 200, an acrylonitrile polymer, dimethylsulphoxide and formaldehyde. The weight ratio of cellulose/acrylonitrile polymer is 0.05 to 1, preferably 0.1 to 1, the weight ratio of formaldehyde/cellulose is 0.2 to 2, and the total concentration of polymer in the solution is 12 to 30% by weight, preferably 18 to 26% by weight.The solutions of the present invention are particularly suitable for the production of filaments consisting of fibrils orientated approximately along the axis of the fibre and closely interwoven, with the cellulose macromolecules being partially involved in a crystal lattice characteristic of cellulose II. The filaments possess valuable properties for use in textiles, such as, for instance, in garments.

Abstract: Polymer powder is dispersed in a combination of an organic solvent for the powder and sufficient water to prevent dissolution of the powder in the organic solvent. The system is heated and the powder is dissolved in the solvent-water system. Water is thereafter removed and the system concentrated.

Abstract: A process for improving the comfort of garments made from acrylonitrile polymer filaments by incorporating in the filaments, a polymer obtained by cross-linking a polyether with an isocyanate.

Abstract: A system for producing coated, oriented polymer film. Methods and apparatus are provided for forming a continuous film of the polymer with water uniformly dispersed therein and applying an aqueous coating composition to at least one surface of the film. The film is oriented and dried under constraint to remove water from the substrate film and coating.

Abstract: A method of manufacturing a microporous hollow fiber having a high permeability to water characterized in that a spinning solution of (A) polyacrylonitrile, (B) an acrylonitrile copolymer, or (C) an admixture of (A) and (B) in an organic solvent is extruded from an annular slit, while simultaneously extruding an organic core liquid which is a solvent for (A), (B) and (C) or a swelling agent capable of swelling them from an orifice encircled by the annular slit and introducing the extruded spinning solution with the core liquid into an aqueous coagulating bath to coagulate the spinning solution to form the hollow fiber.

Abstract: The invention relates to flame-retarding filaments and fibers and a process for the manufacture thereof. The filament-forming substance is a mixture of from 20 to 70 weight % of an acrylonitrile copolymer A containing at least 80 weight % of acrylonitrile units and from 0.3 to 20 weight % of other units copolymerizable with acrylonitrile, and from 80 to 30 weight % of an acrylonitrile copolymer B containing from 50 to 75 weight % of acrylonitrile units, from 25 to 45 weight % of vinyl chloride and/or vinylidene chloride units and from 0 to 5 weight % of other units copolymerizable with acrylonitrile.The filaments and fibers have a boil-off shrinkage of at least 20% and a knot strength of at least 10 cN/tex and are obtained by spinning the turbid solutions of the copolymer mixture, which however do not separate into components, in an aprotic solvent, and drawing of the filaments in a moderate ratio.

Abstract: New polymer solutions, processes for producing such solutions, shaped articles made from these solutions, and process of making such articles, are disclosed. The polymer solutions contain cellulose having a degree of polymerization of at least 200, an acrylonitrile polymer, dimethylsulphoxide and formaldehyde. The weight ratio of cellulose/acrylonitrile polymer is 0.05 to 1, preferably 0.1 to 1, the weight ratio of formaldehyde/cellulose is 0.2 to 2, and the total concentration of polymer in the solution is 12 to 30% by weight, preferably 18 to 26% by weight.The solutions of the present invention are particularly suitable for the production of filaments consisting of fibrils orientated approximately along the axis of the fibre and closely interwoven, with the cellulose macromolecules being partially involved in a crystal lattice characteristics of cellulose II. The filaments possess valuable properties for use in textiles, such as, for instance, in garments.

Abstract: Anisotropic hollow fiber membranes comprising polymer of acrylonitrile and styrene are prepared by extruding a solution of a hollow fiber-forming polymer comprising polymer of acrylonitrile and styrene in a liquid carrier through an annular spinnerette to form a hollow fiber precursor, and the hollow fiber precursor is coagulated in a liquid coagulant comprising water to form a hollow fiber membrane. The liquid carrier used in the method comprises N,N-dimethylformamide and preferably contains non-solvent for the polymer of acrylonitrile and styrene. The hollow fiber membranes have a homogeneously-formed thin selective skin on an open cellular support and exhibit high resistance to collapse. The membranes are especially useful for the separation of gases.

Abstract: The invention relates to a process for the production of hydrophilic filaments and fibres from a filament-forming synthetic polymer by a wet- or dry-spinning process which comprises introducing into the spinning solvent from 5 to 50% by weight of a substance with special properties defined herein and from 0.05 to 5% by weight of at least one surface-active compound as well as to hydrophilic filaments and fibres produced by such process.

Abstract: An acrylic fiber having linen- or cotton-like feeling, dry feeling, a high hygroscopicity and a high water retentivity, which is characterized in that said fiber is covered on the outside with creases running along the fiber axis, adjacent creases being 0.1 to 5.mu. apart on the average; has in any of its cross-sections two or more macrovoids, 2.mu. or more in major diameter, which extend in the direction of fiber axis; and said fiber has 30 to 150 microcrimps per 25 mm of fiber length. A method for producing such a fiber is also disclosed.

Abstract: Continuous film production from a high pressure feed stream is achieved in a system which provides methods and means for maintaining pressurized gas in an extrusion zone wherein the extrudate may be cooled to form a solid polymeric film. The product film is withdrawn from the extrusion zone continuously through a standing liquid column in fluid communication with the extrusion zone. The film is passed downwardly into a liquid leg below the extrusion zone and upwardly through the liquid column, which has an upper exit end elevated above the pressurized zone thereby exerting super-atmospheric pressure. The product is recovered from the liquid sealing medium, advantageously water, at ambient pressure. Hot aqueous solutions of polyacrylonitrile may be extruded at elevated pressure onto a cooled casting drum in a gaseous environment wherein flashing of the hot solvent is prevented.

Abstract: A process for producing preoxidized fiber spun yarns is described comprising subjecting an acrylonitrile fiber tow to a preoxidation, applying a surface active agent, stretch cutting without crimping, crimping to form slivers, processing in a gilling step, and spinning; according to this process, short fibers and powders of fibers are formed to a lesser extent, and nebs, slubs and flies, etc. are caused to a lesser extent, and preoxidized fiber spun yarns having high quality are obtained in a high yield.

Abstract: A novel system for producing film by extruding and/or casting at least two layers of resin, such as polyacrylonitrile homopolymer or interpolymers. The system provides for co-extruding a continuous multi-layer film with contiguous or tandem dies from a first supply of homogeneous resin solution and a second supply of non-homogeneous redissolved resin scrap. The film may be cast onto a smooth cooled drum surface to form substantially continuous adjacent layers from two or more resin supplies. By stripping the film from the drum as a continuous film strip and stretching the film an oriented structure is provided. Scrap resin, such as selvage trimmed from the stretched film or mill scrap, is comminuted and redissolved in solvent for recycle to the second supply of the extrusion step. The homogeneous layer prevents film disruption by inhomogeneities present in the contiguous layer containing redissolved scrap, which might cause localized stresses in the film and discontinuities during stretching.

Abstract: Modacrylic fibres from acrylonitrile, vinylidene chloride, and a sulphonated comonomer, having reduced inflammability and high glossiness and dye yield are prepared by wet spinning a polyblend obtained by mixing two binary copolymers, the first from acrylonitrile and the sulphonated comonomer, and the second from acrylonitrile and vinylidene chloride. As the sulphonated comonomer, a significantly homopolymerizable monomer is used, viz. a monomer which homopolymerizes with a conversion of at least 30-40% by weight, in the presence of azobisisobutyronitrile catalyst, under given standard reaction conditions. Preferred sulphonated monomers are acid or salts of the acrylamidoalkanesulphonic series. The spinning dope is a polyblend solution in an organic solvent chosen among dimethylformamide, dimethylacetamide, and dimethylsulphoxide, mixed with water.

Abstract: A method for preparing flame-resisting modacrylic fibers containing pentaent antimony oxide is described wherein the antimony oxide is suspended in a mixture of water and an organic solvent selected from dimethylformamide and dimethylacetamide and the suspension is then mixed with the viscose solution of the modacrylic polymeric material to be spun. The process yield high luster, flame-resisting modacrylic fibre of the "L.O.I. uprated" type.

Abstract: The invention relates to a process for the stabilization of a spinning solution of an acrylonitrile polymer and a solvent which comprises adding from 0.005 to 0.5% based on the quantity of polymer of at least one stabilizer selected from a polyfunctional phosphonic acid, a phosphonocarboxylic acid or a polymer containing phosphonic acid and/or carboxyl groups to the spinning solution as well as to such stabilized spinning solutions.

Abstract: The method for making bicomponent filaments from two spin dopes wherein the dopes are assembled into alternating layers in a feed tube leading to a transition tube connected to a conventional spinnerette, the layers then being fed through the transition tube and the spinnerette to form filaments. The feed tube has a constant cross-sectional area along the length thereof and the transition tube has a parabolic configuration such that the linear flow rate of the assembled dope layers passing through the transition tube decreases at a uniform rate as the cross-sectional area of the stream of assembled layers is increased to the cross-sectional area of the spinnerette, to thereby maintain the distinctness of the interfaces of the layers and thus insure that good bicomponent filaments will be formed.

Abstract: A process for producing polyacrylonitrile membranes for use in reverse osmosis, which comprises dissolving an acrylonitrile polymer in formamide (FA)-containing dimethylformamide (DMF) to prepare an acrylonitrile polymer solution for membrane formation; shaping the solution into a membranous product of a desired form while maintaining the temperature of the solution within a specific range; removing the solvent from the membranous product under a specified solvent removal condition (solidifying condition); subjecting the thus-obtained membrane to a heat treatment, and further to a plasma treatment. The polyacrylonitrile membrane thus obtained is asymmetric and porous in structure, and excellent both in separation ability and in mechanical strength. This membrane is very suitable for use in reverse osmosis.

Abstract: A method is disclosed for embedding sequestering agents in filamentary structures, the method comprising the steps of preparing an emulsion formed by an aqueous or nearly aqueous solution of the sequestering agent and a solution of the filament-forming polymer in an appropriate solvent, and spinning the emulsion in a coagulation bath.

Abstract: Acrylic yarns and fibers having a high shrinkage power, ranging up to 50%, obtained by wet spinning, a stretching of 1.3 to 3 .times. in air, washing, a stretching of 1 to 2.5 .times. into boiling water, drying, steaming at 105.degree.-150.degree. C., over-stretching of 1.2 to 2 .times. at 90.degree.-100.degree. C.

Abstract: Acrylonitrile polymers containing at least 91% by weight acrylonitrile are spun from solutions having a polymer concentration of 38 to 75% by weight. Useful polymers have an intrinsic viscosity of 0.6 to 2.0, most preferably 0.9 to 1.1, 7 to 23 .mu.eq./g. enolizable groups after mild acid treatment, 15 to 70 .mu.eq./g. thioether ends derived from a water insoluble mercaptan and less than 3 .mu.eq./g. oxidizable hydrolysis fragments.

Abstract: Modacrylic fibers having high retraction, reduced inflammability and high glossiness, prepared by wet spinning a solution, in an organic spinning solvent miscible with water, of a mixture of copolymers from acrylonitrile, vinylidene chloride, at least a vinyl ester and at least an unsaturated monomer containing at least a sulphonic group, the acrylonitrile units being from 50% to 85% by weight and the vinyl ester units from 3% to 6% by weight; hot drawing the coagulated fiber in a mixture of water and spinning solvent; drying the fiber in hot air while leaving it free concurrently to contract; and subsequently further hot drawing it in air.

Abstract: Textile fibers having reduced inflammability and high luster, constituted copolymers of acrylonitrile, vinylidene chloride and a significantly homopolymerizable sulphonic comonomer are described. Significantly homopolymerizable comonomers are defined as monomers which homopolymerize with a conversion above 30.degree.-40.degree. under standard conditions set forth in the specification. A preferred class of such comonomers are the derivatives of acrylamidoalkanesulphonic acids, e.g. 2-acrylamido-2-methylpropane-sodium sulphonate. The fibers are spun from spinning dopes containing said copolymers in solution in organic solvent miscible with water and less than 4% of water. Said spinning dopes can be obtained by preparing a binary copolymer of acrylonitrile and the sulphonic monomer, in solution in the solvent, mixing the solution with a solution of acrylonitrile and vinylidene monomers in the same solvent, and subjecting the mixture to copolymerization.

Abstract: Modacrylic fibres from acrylonitrile, vinylidene chloride, and a sulphona comonomer, having reduced inflammability and high glossiness and dye yield are prepared by wet spinnning a polybend obtained by mixing two binary copolymers, the first from acrylonitrile and the sulphonated comonomer, and the second from acrylonitrile and vinylidene chloride. As the sulphonated comonomer, a significantly homopolymerizable monomer is used, viz. a monomer which homopolymerizes with a conversion of at least 30-40% by weight, in the presence of azobisisobutyronitrile catalyst, under given standard reaction conditions. Preferred sulphonated monomers are acid or salts of the acrylamidoalkanesulphonic series. The spinning dope is a polyblend solution in an organic solvent chosen among dimethylformamide, dimethylacetamide, and dimethylsulphoxide, mixed with water.

Abstract: Process for the production of small tubing, e.g., hollow fibers comprising(a) preparing a solution of an organic fiber-forming polymer, containing, in a uniformly dispersed form, a sinterable inorganic material;(b) extruding the inorganic material-containing polymer solution through a hollow fiber spinneret;(c) forming a polymeric precursor hollow fiber, laden with the inorganic material;(d) treating the polymeric precursor hollow fiber to remove the organic polymer; and(e) sintering the resulting inorganic material in hollow fiber form.

Abstract: Acrylic synthetic fibers highly resistant to pilling and having good dyeability can be produced by specifying the composition of the acrylic polymer, the condition of the primary stretching step, the internal water content of the water-swollen gel fibers, the conditions of the steps of the drying-compacting, secondary stretching and relaxing heat treatment.

Abstract: Filamentary vinyl polymer compositions are commonly prepared according to the following procedure:(a) polymerizing a vinyl monomer in a concentrated aqueous inorganic salt solution to produce a vinyl polymer solution;(b) spinning the resulting vinyl polymer solution into a coagulating bath containing an aqueous solution of the same inorganic salt as that employed in the polymerization step, the concentration of inorganic salt in the coagulating bath being maintained at a level which affords precipitation of the vinyl polymer to form a coherent filamentary gel;(c) washing the gel so produced;(d) recovering the concentrated aqueous inorganic salt solution from the washing and coagulation steps; and(e) recycling the recovered concentrated aqueous inorganic salt solution into the polymerizing step. In such a process, undesirable copper ion impurities accumulate in the recovered concentrated aqueous inorganic salt solution.

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: There is disclosed a method of producing hydrogel tubes comprising partially hydrolyzing an acrylonitrile-containing polymer in an inorganic acidic solvent solution at temperature of about -10.degree. to 50.degree. C., extruding said hydrolyzed polymer solution through a circular nozzle into an aqueous coagulating bath, the same or similar coagulating bath simultaneously being fed through a central tube or pin of the nozzle.Preferably, the surface of the tube is made very slippery in wet condition, by treating it with chemical agents causing either a further hydrolysis or other reaction leading to carboxylic, sulfonic or sulfuric groups, or an esterification with polyols such as glycerol, glycols or polyvinyl alcohol, preferably with simultaneous sulfonation or sulfuration.

Abstract: Hollow fibers of acrylonitrile polymers having water-permeability greater than 0.2 ml/cm.sup.2.min.atm and useful as an inexpensive superior ultrafilter, comprising(1) a porous layer or layers existing on the outer or/and inner sides of said hollow fibers, the average sizes of pores contained in said porous layer or layers and existing on each of assumptive cylindrical surfaces concentric with the central axis of said hollow fibers, having such a gradient that the average sizes of pores contained in the porous layer existing on the outer side become smaller toward the outer surface of said hollow fibers while the average sizes of pores contained in the porous layer existing on the inner side become smaller toward the inner surface of said hollow fibers, and(2) a reticulate porous layer adjacent to said porous layer or layers (1) and containing therein at least one succession of voids having diameters of at least 10-50 .mu.

Abstract: The invention relates to a method of manufacturing shaped articles from crystalline or quasi-crystalline acrylonitrile polymers and copolymers, said method consisting in cooling down a solution of said polymer or copolymer in a mixture containing from 50 to 99.5% by weight of a solvent and from 0.5 to 50% by weight of a precipitant to a temperature below the gelation point of the solution until the same gelatinizes, without changing its composition, to the desired shape, whereafter the solvent is removed from the shaped thermoreversible gel thus obtained at temperatures lower than the gelation point of the solution, preferably using a liquid precipitant of polyacrylonitrile miscible with the solvent. It is advantageous to remove the solvent at a temperature which is at least 10.degree. C. lower than the gelation temperature of the polymer solution used. The shaping can be carried out in any convenient way, e.g. using a stationary or rotating mold.

Abstract: A vinylidene chloride copolymer film having excellent bubble stability in an inflation-stretching process and excellent cold resistance is prepared by inflation-stretching a tubular amorphous substance obtained by melt-extruding and quenching a composition comprising vinylidene chloride copolymer, a miscible type elastomer (A component) and a particle dispersion type elastomer (B component) in a range surrounded by the lines (a), (b), (c) and (d) ##EQU1## WHEREIN A WEIGHT PERCENT OF THE B component to total elastomers is plotted on X axis (abscissa) and a weight percent of total content of the A component and the B component to total components is plotted on Y axis (ordinate).

Abstract: The invention relates to a bi-component filament or fibre of a fibre-forming synthetic polymer having a core/sheath structure in at least one component and having a moisture absorption of at least 1.5% at 65% relative atmospheric humidity and at a temperature of 21.degree. C. and a moisture absorption of at least 5% at 90% relative atmospheric humidity and 21.degree. C. and a water-retention-power of at least 10% as well as to a process for the production thereof.

Abstract: An acrylonitrile polymer film is produced by the steps of:Extruding an acrylonitrile polymer solution in a tubular shape into a coagulation liquid bath while a coagulation liquid is introduced into and withdrawn from the inside of the extruded tubular-shaped film;Removing the solvent remaining in the coagulated tubular film, and;Biaxially stretching the tubular film containing 5 to 23% by weight of water based on the dry weight, at a temperature of 100.degree.-170.degree. C. at least twice its original length both in the longitudinal and transverse directions by a tubular stretching procedure.

Abstract: This invention relates to a process for preparing fibrous materials by wet method. Fibrous materials with excellent properties can be obtained by feeding the starting solution to the interface area of two phases of the coagulation bath.

Abstract: The invention relates to a process for the production of crosslinked fibres or filaments by spinning an acrylonitrile copolymer containing at least 20 mVal of carboxyl groups per kg of polymer together with a polyoxazoline in a polar organic solvent and thereafter crosslinking at temperatures of from 120 to 190.degree. C.The invention also relates to crosslinked acrylonitrile fibres and filaments obtainable by this process.

Abstract: A process for preparation of a metal carbide-containing molded product which comprises heating a molded composition comprising at least one powdery metal selected from the group consisting of B, Ti, Si, Zr, Hf, V, Nb, Ta, Mo, W, Cr, Fe and U and having an average particle size of not more than about 50 .mu. and an acrylonitrile polymer at a temperature of about 200.degree. to 400.degree. C and then calcining the resulting product at a temperature of about 900.degree. to 2500.degree. C in an inert atmosphere.