METHOD FOR PREPARING HOMOGENEOUS BRAID-REINFORCED PPTA HOLLOW FIBER MEMBRANE

摘要

A method for preparing a homogeneous braid-reinforced (HMR) PPTA hollow fiber membrane combines PPTA hollow tubular braids with PPTA surface separation layer. The method includes following steps of: (1) preparing the PPTA hollow tubular braids, wherein the PPTA hollow tubular braids which are made from PPTA filament yarns are woven by a two-dimensional braided method, the outer diameter of the PPTA tubular braids is 1-2mm; (2) preparing the PPTA casting solution as the surface separation layer, wherein the 1-3wt% PPTA resin, 0-2wt% inorganic particles and 10-20wt% pore-forming agents are mixed into 75-89% inorganic acid solvent, stirred for 1-3 hours at 70°C-90°C to form homogeneous and transparent casting solution; and (3) preparing reinforced PPTA hollow fiber membrane, wherein the casting solution as the surface separation layer is evenly coated on the surfaces of the PPTA hollow tubular braids through spinneret, and they are immersed in a coagulation bath for solidified formation.