METHOD FOR PREPARATION OF BETA CRYSTALLINE PHASE POLYVINYLIDENE FLUORIDE HOLLOW FIBER MEMBRANE

摘要

Provided is a method for preparation of a fluoride hollow fiber membrane, particularly a method for preparation of a beta crystalline phase polyvinylidene fluoride hollow fiber membrane with high flux and high strength involving a thermally induced phase separation process. The method comprises subjecting a porous membrane prepared via a thermally induced phase separation process to a continuous post-processing process consisting of a combination of stretching and annealing, so as to obtain polyvinylidene fluoride with a content of beta crystalline phase as high as possible. The polyvinylidene fluoride hollow fiber membrane prepared by the method not only possesses much higher strength but also possesses higher water-flux as compared with an unprocessed one.