THE MANUFACTURING METHOD FOR ULTRAFILTRATION FILM

摘要

The hollow fiber membrane for an ultrafiltration is mfd. by (a) adding an inorganic salt and an alcohol cpd. to the soln. of polysulfone and polar organic solvent to obtain a spinning soln., (b) spinning the spinning soln. from the outer tube of the double tubular nozzle to the outer solidifying liquor-filled bathtub, spinning the inner solidifying agent in the inner tube, and then winding and drawing it to form a porous network-like layer on the inner surface, and (c) contacting the spinning soln. with the outer solidifying agent, and then phase inverting it to form a dense skin layer having micropores, and the fingure structure. The membrane has a good water-permeability and mechanical tenacity.