PREPARATION OF HOLLOW YARN COMPOSITE MEMBRANE

摘要

PURPOSE:To prevent a coated polymer material from penetrating into a support, by imparting hydrophilicity ot the surface of a porous hollow yarn support by a surface activator before coating a polymer membrane having separation function. CONSTITUTION:About 0.5-1wt% aqueous anion activator solution is applied to the outer periphery of a porous hollow yarn support 6 having a void ratio of 30-80% and an average pore size of 0.1-0.5mum and dried. To the outer periphery of the surface modified porous hollow yarn support, an org. solvent solution(2-4wt%) of a polymer membrane forming material having separation function is applied and dried to coat a polymer membrane 7 to obtain a composite membrane. The application is performed by immersing the hollow yarn in said solvent solution for about 2-10sec.