MICROPOROUS POLYVINYLCHLORIDE MEMBRANE AND PREPARATION METHOD THEREOF

摘要

PURPOSE: A process for manufacturing a microporous polyvinylchloride membrane via solvent induced phase separation(SIPS) is provided to control pore morphology such as pore size and porosity to be suitable for microfiltration, where especially the flux of pure water is improved as nonsolvent concentration increase, and further in the case that the nonsolvent is either n-propyl alcohol or n-butyl alcohol, the flux of pure water is improved as relative humidity increase within relative humidity range 50 to 90%. CONSTITUTION: The process for microporous polyvinylchloride membrane includes: dissolution of polyvinylchloride into tetrahydrofuran(THF) solution; addition of 1-40wt.% of an alcohol selected from n-propyl alcohol or n-butyl alcohol, which is miscible with the tetrahydrofuran(THF) while acting as a nonsolvent to the polyvinylchloride; coating non-woven polyester fabric with a mixed solution obtained in 2nd step; drying at 25deg.C under the atmosphere of relative humidity of 50 to 90%. The microporous polyvinylchloride membrane has overall porosity of 25-80%, pore size distribution within range of 0.01 to 2μm and it has a net flux of 25 to 7000LMH.