PRODUCTION OF GAS SEPARATION MEMBRANE HAVING ASYMMETRIC POLYSULFONE

摘要

PURPOSE:To obtain a gas separation film having an excellent permeation rate of oxygen and a selectivity for oxygen and nitrogen by dissolving soluble aromatic polysulfone having a specified structural unit in a polar solvent to prepare a polymer solution and then removing the solvent from the solution. CONSTITUTION:An soluble aromatic polysulfone expressed substantially by (X-Y)n, wherein X and Y are the structural units expressed by formulae I and II, respectively, is dissolved in a polar solvent such as N,N- dimethylacetoamide, to prepare a polymer solution. In the formulae, R1-R4 represent H, CH3, or C2H5, R5 and R6 are H or an electron attractive group. This solution is brought into contact with such a solidifying liquid that is soluble with the solvent but insoluble with the polysulfone to remove the solvent from the polymer solution. Thus, the obtd. gas separation film composed of asymmetric polysulfone has excellent the permeation rate for oxygen, excellent nitrogen- oxygen selectivity, heat resistance, chemical resistance and mechanical strength.