Preparation method of polyvinylidene fluoride hollow fiber composite microporous film with strong interface binding power

Abstract

The invention discloses a preparation method of a polyvinylidene fluoride hollow fiber composite microporous membrane which has strong interfacial bonding force. The preparation method comprises the following steps: 1) neutral or amphiphilic substances which have good bonding force with braided fiber tubes and the polyvinylidene fluoride are prepared into dilute solution; 2) the dilute solution of the neutral or amphiphilic substances is coated once on the braided fiber tubes; 3) casting membrane liquid is used for secondary coating on the coated braided fiber tubes, and the polyvinylidene fluoride hollow fiber composite membrane is obtained by a solution phase transition method; 4) post-hydrophilization treatment is carried out; 5) the polyvinylidene fluoride hollow fiber composite membrane is cleaned and dried to obtain the hydrophilic polyvinylidene fluoride hollow fiber composite microporous membrane. The preparation method takes the braided fiber tubes as supporting tubes, uses an amphiphilic copolymer and the polyvinylidene fluoride to be blended, and prepares the polyvinylidene fluoride hollow fiber composite microporous membrane which has strong interfacial bonding force, hydrophilicity, pollution resistance, large flux, high interception rate and high mechanical strength by the solution phase transition method.

Description

technical field [0001] The invention belongs to the technical field of preparation and modification of polyvinylidene fluoride (PVDF) separation membrane materials, and in particular relates to a preparation method of a polyvinylidene fluoride hollow fiber composite microporous membrane with strong interfacial binding force. Background technique [0002] Polyvinylidene fluoride (PVDF) hollow fiber microporous membrane has good chemical stability and thermal stability, so it has been widely used in industrial and municipal sewage treatment, drinking water purification, reclaimed water reuse, biomedicine, etc. fields. At present, the following problems mainly exist in the use of PVDF hollow fiber microporous membranes: (1) PVDF microporous membranes have poor hydrophilicity and are easy to pollute; (2) the water flux and interception of the membrane cannot be improved at the same time; (3) the membrane The mechanical strength of the film is not high, so that the rupture of th...

AI Technical Summary

Problems solved by technology

At present, the following problems mainly exist in the use of PVDF hollow fiber microporous membranes: (1) PVDF microporous membranes have poor hydrophilicity and are easy to pollute; (2) the water flux and interception of the membrane cannot be improved at the same time; (3) the membrane The mechanical strength is not high, so the rupture of the membrane occurs during use

The compatibility of the above-mentioned polymer fibers with PVDF is poor, so the interfacial binding force between the fiber braided support tube and the PVDF membrane in the prepared hollow fiber composite microporous membrane is weak

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