Hydrophilic sulfonated polyolefin porous membrane and process for preparing the same

摘要

A sulfonated polyolefin porous membrane containing sulfonic groups in an amount, in terms of exchange capacity, of 0.05 to 1 milliequivalent per gram of the sulfonated polyolefin and having a porosity of 30 to 85% and an average pore diameter of 0.05 to 1 mu has been found to be excellent in water permeability, removal capability, water-permeability retention, mechanical strength and elongation, etc. The porous membrane of the present invention may advantageously be employed as a fine microfilter or the like. The porous membrane of the present invention may be easily prepared by treating with a sulfonating agent a polyolefin porous membrane preferably containing an inorganic filler which is subsequently extracted from the membrane.