Amphipathic three-block polymer PS(x)MAA(y)-g-fPEG(z) modified PVDF ultrafiltration membrane and preparation method thereof

Abstract

The invention provides an amphipathic three-block polymer PS(x)MAA(y)-g-fPEG(z) modified PVDF ultrafiltration membrane and a preparation method thereof. PS(x)MAA(y)-g-fPEG(z) is used as an additive for modifying PVDF to obtain the amphipathic three-block polymer PS(x)MAA(y)-g-fPEG(z) modified PVDF ultrafiltration membrane. The amphipathic three-block polymer PS(x)MAA(y)-g-fPEG(z) modified PVDF ultrafiltration membrane is prepared by adopting an immersion precipitation phase inversion method, the modified membrane can keep long-time stability. According to the method, the adopted additive is prepared by simple free radical polymerization and normal temperature esterification reaction, the operation is simple, the use rang is wide, and compared with the prior art, the method is few in operation steps, simple and convenient to operate, low in cost and easy to implement in commercial production; as a PS chain section in the additive-PS(x)MAA(y)-g-fPEG(z) has good compatibility with PVDF, the modified membrane is relatively stable in the using process and not liable to disappear; an MAA(y) chain section in the additive-PS(x)MAA(y)-g-fPEG(z) is enriched on the surface of the PVDF, so that the hydrophily of the modified PVDF membrane is good, the contact angle of the membrane with water is small, the water drop seepage velocity is high, and tight contact of pollutants on the surface of the membrane is prevented.

Description

technical field [0001] The invention relates to the technical field of polymer design and synthesis and membrane separation, in particular to an amphiphilic triblock polymer PS x MAA y -g -fPEG z Synthesis and modified polyvinylidene fluoride (PVDF) ultrafiltration membrane and its preparation method. Background technique [0002] Membrane separation technology has the advantages of small footprint, high pollutant removal efficiency, and no secondary pollution to the environment. It has often become the preferred method to solve environmental and resource problems in the field of water treatment. [0003] Crystalline polymer polyvinylidene fluoride (PVDF) has good chemical stability, heat resistance, mechanical stability, and can be dissolved in N-methylpyrrolidone (NMP), N,N-di Strong polar organic solvents such as methylacetamide (DMF) or dimethyl sulfoxide (DMSO) are easy to form membranes by phase inversion, and are ideal materials for preparing new polymer membranes ...

AI Technical Summary

Problems solved by technology

[0009] In view of the above-mentioned shortcoming of the prior art, the purpose of the present invention is to provide a kind of simple and easy method, to solve the strong hydrophobicity of conventional PVDF membrane (comprising flat membrane and hollow fiber membrane), the water flux is low, in the separation process Susceptible to the irreversible pollution of organic matter such as protein and oil

[0010] Another purpose of the present invention is to solve the technical problems of cumbersome methods for synthesizing PVDF membrane hydrophilic modification additives in the prior art, high cost and high operation requirements, and the technical problems that metal salt catalysts are not easy to remove and not easy to industrialize in some reactions

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