Method for preparing compound hollow fibrous membrane

Abstract

The invention discloses a method for preparing a compound hollow fibrous membrane, comprising the following steps: using a solution phase transfer hollow fibre spinning technique to make polrvinyl chloride or copolymer thereof, solvent and pore-forming agent into basal membrane spinning liquid of compound hollow fibrous membrane, making polyvinylidene fluoride or copolymers thereof or mixture of both, solvent and pore-forming agent into compound layer spinning solution, extruding the two spinning fluids through a spinning nozzle of the hollow fibre spinning machine and core liquid in a central pore of spinning head simultaneously, and then entering into outer coagulating bath; and preparing the compound hollow fibrous membrane after the solvents and pore-forming agents in the two prepared spinning fluids enter into condensed liquid phase, and polymer used as the material of a compound layer and a basal membrane is settled into polymer hollow fibrous membrane by phase shift. The invention uses polrvinyl chloride or copolymer thereof as basal membrane materials, and has lower material cost, and higher mechanical strength compared with the prior art; the performances of the basal membrane and compound layer materials are right complementary; besides, polrvinyl chloride or copolymers thereof have various types and are wide for selection.

Description

technical field [0001] The invention relates to a preparation method of a composite hollow fiber membrane, in particular to a preparation method of a high-strength, high-throughput hydrophilic composite hollow fiber porous membrane. Background technique [0002] Chinese invention patent 200610035536.2 discloses a preparation method of a composite hollow fiber membrane, which uses a solution phase transfer hollow fiber spinning process to make polyethersulfone or polysulfone, solvent, and pore-forming agent into a base membrane spinning composite hollow fiber membrane. Silk liquid, polyvinylidene fluoride or its copolymer or a mixture of the two, solvent, and pore-forming agent are made into a composite layer spinning liquid of a composite hollow fiber membrane, and the above two spinning liquids are passed through the hollow fiber spinning machine. The spinneret and the core liquid in the central tube hole of the spinneret are extruded at the same time, and then enter the ou...

AI Technical Summary

Problems solved by technology

The preparation method of this composite hollow fiber membrane uses polyethersulfone or polysulfone as the main raw material of the base membrane spinning solution, which not only has high cost, but also has insufficient strength.