Study on the reconstruction of crystalline polymer porous membrane pore channels via confined-region swelling effect

Abstract

Herein, a novel strategy to reconstruct the pore channels of crystalline polymer porous membrane is reported. The method is based on the property that molecular chains in amorphous regions of the crystalline polymer are in the high elasticity form, and the swelling of amphiphilic macromolecules used to reconstruct the pore channel in the amorphous region of membrane. The hydrophilic polyvinylidene fluoride (PVDF)/PVDF-graft-poly (ethylene glycol) methyl ether methacrylate (PVDF-g-PEGMA) blended membrane was prepared. Then the reconstruction of membrane pore channel is based on that the PVDF chains in the amorphous regions are in the high elasticity form and the swelling property of PEGMA chains. After the reconstruction of membrane pore channel, the pore size decreased from 164.2 to 73.5 nm and the membrane flux increased from 670 to 1298 L·m−2·h−1. This strategy of membrane pore channel reconstruction can not only improve the membrane hydrophilicity and flux, but also avoid the adverse influence accompanied by conventional methods on the pore size and mechanical strength, which is an innovative and effective method to prepare the antifouling and high-flux porous membrane.