Abstract: A synthetic membrane consisting of a mixture of polysulfone and sulfonated polysulfone and not more than 20 wt. % of other polymers, characterized in that the mixture contains 0.5 to 8 wt. % sulfonated polysulfone, possibly as the salt of sulfonic acid, and a method for manufacturing this synthetic membrane, characterized in that one or more solvents are added to a mixture composed of 0.5 to 8 wt. % sulfonated polysulfone, possibly as the salt of sulfonic acid, polysulfone and not more than 20 wt. % of other polymers, the mixture is dissolved to form a polymer solution, the latter is shaped, and precipitated to form a membrane in a precipitating bath by means of one or more precipitating agents.

Abstract: An asymmetric semipermeable membrane for dialysis and/or ultrafiltration is composed of a copolymer of acrylonitrile and acrylic ester and an ionic or ionizable monomer in the form of a hollow fiber. The copolymer is composed of 90.50 to 95.00 wt. % acrylonitrile, 4.99 to 8.60 wt. % acrylic ester, and 0.01 to 0.90 wt. % of the ionic or ionizable monomer. Also provided is a process for its manufacture.

Abstract: A method for production of polycarbonate-polyether-blockcopolymers is provided. One or more solutions comprising bisphenol A and polyalkyleneglycol and a phosgene solution are added to a cooled initial reaction medium in a cooled reaction chamber in such a way that the phosgene contacts substantially the reaction partners from the one or more cooled solutions after they have spread in the reaction medium. Preferably the phosgene solution and the one or more solutions are added through tubes ending above the liquid level of the reaction medium such that the solutions added contact only within the stirred reaction mixture the reaction partner. The phosgene is employed in an excess of less than about 10 weight percent of the stochiometrically required weight amount relative to bisphenol A and polyalkyleneglycol. The polymer is useful in the production of membranes for dialysis, ultrafiltration and reverse osmosis.