CELLULOSE ACETATE SEMIPERMEABLE DIAPHRAGM IN THE FORM OF HOLLOW FIBRE, METHOD OF MANUFACTURE OF HOLLOW-FIBRE SEMIPERMEABLE CELLULOSE ACETATE DIAPHRAGM, HEMODIALYZER AND APPARATUS FOR TREATMENT OF EXTRACORPOREAL BLOOD Russian patent published in 1998 - IPC

FIELD: manufacture of semipermeable diaphragms for purification of aqueous biological fluids, in particular, for purification of extracorporeal blood by means of hemodialysis. SUBSTANCE: diaphragms have preferably the shape of hollow fibres. They are manufactured of hydrophilic polymeric material, preferably of cellulose acetate. The diaphragms have the following characteristics: ultrafiltration factor ((K_uf)) - within 15 to 55 ml/h mm HG sq.m, mass-transfer coefficient for urea /K_ov(urea)/38•10^-3 cm/min, minimum, and ratio/ K_ov(urea)/ /K_uf-2,5•10^-3, minimum. Hollow fibres of such diaphragms suitable for hemodialyses have a diameter of internal passage within 175 to 210 um and wall thickness within 10 to 35 um. In accordance with the described methods of manufacture of diaphragms, the melt containing 32 to 40 mass percent of cellulose acetate, 5 to 10 mass percent of glycerin, and 50 to 65 mass percent of polyethylene glycol is extruded and hollow fibres are obtained; fibres are cooled down, subjected to cold extraction, washed out with water and replasticized by a solution of glycerin. EFFECT: enhanced efficiency. 21 cl, 5 dwg, 4 tbl