Melt-spinning preparation method of polyvinylidene fluoride hollow fiber filter membrane

Abstract

A melt-spinning preparation method of a polyvinylidene fluoride hollow fiber filter membrane includes steps: S1, subjecting, by weight, 18-35 parts of polyvinylidene fluoride, 10-30 parts of a solvent, 40-60 parts of inorganic particles, 1-3 parts of a coupling agent and 2-6 parts of a hydrophilic polymer to high-speed mixing at the room temperature to obtain uniform mixed powder; extruding the mixed powder at 170-220 DEG C through a double-screw extruder to obtain uniform particles. The method has advantages that an inorganic filler material, the organic solvent, the coupling agent and a macromolecular pore-forming agent are highly mixed and blended through the double-screw extruder to form the uniform particles; then an annular spinneret plate of a single-screw extruder is adopted for making the uniform particles into fibers; the fibers are subjected to stretching, acid soaking and washing to obtain the hollow fiber filter membrane. In addition, member fibers produced according to the method has advantages of simple production process, low cost, high flux and uniformity in pore forming.

Description

technical field [0001] The invention relates to the field of preparation of hollow fiber microfiltration membranes, in particular to a method for preparing polyvinylidene fluoride hollow fiber filtration membranes by melt spinning. Background technique [0002] Membrane separation technology has been extensively researched and developed rapidly in the past 20 years, and various forms of membrane modules have been developed, among which hollow fiber membranes have attracted more and more attention because of their special advantages. It has been maturely used in sewage treatment, petrochemical industry, medicine, food, steel, electric power and many other fields. [0003] At present, the preparation technology of hollow fiber filter membrane mainly includes solution spinning method and melt spinning method. Melt spinning methods include thermally induced phase separation and melt spinning-drawing methods. The thermotropic phase method, as described in ZL98807444.3, is to bl...

AI Technical Summary

Problems solved by technology

Since no suitable coupling agent is added in this method, the added inorganic powder cannot be uniformly dispersed in the membrane-forming system, so the hollow fiber porous membrane produced has a relatively large pore size, and it is necessary to coat a layer on the surface of the fiber membrane. Feed solution for solvent spinning to obtain smaller membrane pores, the spinning process is more cumbersome

And because the bubble cavity is relatively large, a higher concentration of glycerin aqueous solution (55%) is required to maintain the water flux of the membrane filament, which results in a relatively high requirement for the preservation of the membrane filament and the production environment of the membrane module.