POLYVINYLIDENE FLUORIDE BASED COMPOSITE HOLLOW FIBER MEMBRANE, AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a polyvinylidene fluoride based composite hollow fiber membrane enlarging an effective film area by forming recession/projection on the outer surface of the film not depending on a size enlargement method for the hollow fiber membrane using a specific shape-different nozzle, and its manufacturing method.;SOLUTION: In the composite hollow fiber membrane for forming an outer layer of a three-dimensional network structure including a macro-void and the inner layer of a spherical structure, a polyvinylidene fluoride based composite hollow fiber membrane has a wave-shape wrinkle on a surface of the hollow fiber membrane. In the manufacturing method for the polyvinylidene fluoride based composite hollow fiber membrane is manufactured via the step of extruding a resin solution A from the intermediate slit of a triple tubular spinning nozzle, a resin solution B from the outer layer slit of the nozzle and a coagulation liquid from a central pipe in a concentric circle form and cooling/solidifying the external coagulation liquid and the step of removing a solvent. In the manufacturing method for the polyvinylidene fluoride based composite hollow fiber membrane, the external coagulation liquid contains 70 wt.% or more of a non-solvent relative to the resin solution B.;COPYRIGHT: (C)2009,JPO&INPIT