聚偏氟乙烯（PVDF）膜由于其优良的可加工性、化学稳定性、孔径可控和耐热性能而广泛地应用于微滤和超滤过程.但由于PVDF膜表面疏水性强,尤其是应用在油水分离、蛋白类水质分离等方面时,易产生吸附污染.本文合成了一种两亲聚合物并共混到PVDF中,通过相转化法(L-S)制备了改性PVDF平板膜,研究了改性膜在含油废水处理中的应用.通过对浓度为80mg/L～240mg/L含油水的膜分离实验表明,改性膜比纯PVDF膜的截留率和水通量都有显著提高.纯PVDF膜除油率最高达89.1%,而改性膜除油率最高达97.0%.衰减趋稳后,PVDF膜水通量在20 L/m2·h左右,而改性膜水通量稳定在50 L/m2·h左右.

Abstract：Poly(vinylidene fluoride) (PVDF) has widely used as a material of membranes in microfiltration (MF) and ultrafiltration (UF) due to their excellent processability, chemical resistance, well-controlled porosity, and good thermal property. However, there are still some problems for PVDF membranes which limit the further developments and applications of them especially in the areas of purification and separation of aqueous solution systems such as oily wastewater and protein-containing solutions. In this paper, the PVDF material was blended with an amphiphilic polymer and hydrophilic modification of PVDF membranes was prepared by Loeb-Souriraian (L-S) phase inversion method. Then application of the membrane in oily wastewater treatment was detected. The permeation properties measurement of the membrane for wastewater with the oil concentration variable from 80mg/L to 240mg/L indicated that the highest rejection ratio of the modified membrane was up to 97.0% while the pure PVDF membrane was 89.1%. When the attenuation stabled, the permeation flux of the modified membrane and the pure PVDF membrane were around 50 L/m2·h and 20 L/m2·h, respectively.

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