Abstract: The invention relates to a composite polymeric material suitable for biological and medical applications and to the method for preparation thereof. The composite material consists of 1-99 wt. % of hydrophilic polymer or copolymer based on methacrylic or acrylic esters, 1-99 wt. % of fibrillar collagen, and up to 2.5 wt. % of a crosslinking agent, based on both polymeric components. The composite material may further comprise biologically active compounds and other auxiliary materials, as fillers and/or plasticizers. The composite material is prepared by dispersing the fibrillar collagen in a solution or a highly swollen dispersion of the synthetic hydrophilic polymer or copolymer in a lytropic agent and the subsequent removal of the lyotropic agent, thus forming a matrix of the synthetic polymer or copolymer penetrated by fibrillar collagen or vice versa. The composite material may be applied on a solid support or reinforced with glass, plastics, cellulose, or metallic materials.

Abstract: The invention relates to a composite polymeric material suitable for biological and medical applications and to the method for preparation thereof. The composite material consists of 1-99 wt. % of hydrophilic polymer or copolymer based on methacrylic or acrylic esters, 1-99 wt. % of fibrillar collagen, and up to 2.5 wt. % of a crosslinking agent, based on both polymeric components. The composite material may further comprise biologically active compounds and other auxiliary materials, as fillers and/or plasticizers. The composite material is prepared by dispersing the fibrillar collagen in a solution or a highly swollen dispersion of the synthetic hydrophilic polymer or copolymer in a lyotropic agent and the subsequent removal of the lyotropic agent, thus forming a matrix of the synthetic polymer or copolymer penetrated by fibrillar collagen or vice versa. The composite material may be applied on a solid support or reinforced with glass, plastics, cellulose, or metallic materials.

Abstract: A starting monomer mixture containing a minor amount of a cross linking agent is precipitation polymerized in a diluent/precipitant which is an unlimited solvent for the starting monomers but is neither a solvent nor a substantial swelling agent for the resultant polymer. The resultant product falling from the polymerization contains soluble and insoluble hydrophilic polymers and copolymers.

Abstract: A method for the preparation of a hydrophilic acrylonitrile-containing polymer comprising admixing a solution of said polymer in 47% to 75%, preferably 50 to 72% concentrated HNO.sub.3, with solid particles of a substance insoluble in said acid solution and soluble in water, aqueous solutions of said substance being operative to precipitate said polymer from said HNO.sub.3, shaping the mixture of the dissolved polymer with said solid substance to a desired physical shape, coagulating said shaped polymer in an aqueous medium and washing said solid particles out from the coagulated polymer, and articles made therefrom.The added solid substance either may react with nitric acid forming a water-soluble nitrate, or it may remain in the mixture unchanged.

Abstract: The tendon prosthesis of the invention consists of a core formed of from a synthetic, preferably hydrophilic linear polymer oriented substantially in the direction of the main longitudinal axis of the prosthesis, having a tensile strength exceeding 100 kg/cm.sup.2 and an elastic elongation of 8 - 50 percent, preferably 12 - 25 % of the resting length, and a sheath consisting of one or more layers of a hydrophilic, substantially non-oriented, physically or covalently crosslinked polymer with an equal or higher elastic elongation and an approximately equal or higher hydrophilicity than that of said core. The material of the core and particularly that of the sheath are permanently compatible with living tissue.

Abstract: A starting monomer mixture containing a minor amount of a cross linking agent is precipitation polymerized in a diluent/precipitant which is an unlimited solvent for the starting monomers but is neither a solvent or a substantial swelling agent for the resultant polymer. The amount of cross linking agent is maintained during polymerization at a critically low percent by volume relative to the entire polymerization mixture. The resultant product falling from the polymerization contains substantially only soluble hydrophilic polymers and copolymers.