摘要:
合成了一种含氟和羧基的新型聚合物添加剂,全氟烷基-聚乙二醇乙酸[FPEG(COOH)],将其用于聚氯乙烯(PVC)膜的共混改性研究.通过对凝固浴的组成、铸膜液中聚合物的浓度以及添加剂的含量进行考察,探讨了这些因素对膜的结构、表面特性、机械强度以及水通量和分离效率的影响,并通过红外光谱仪(FT-IR)、X射线光电子能谱仪(XPS)和扫描电子显微镜(SEM)对所制备的膜的表面化学特性及断面的结构和形态进行了表征.研究结果表明,含氟聚合物FPEG(COOH)的添加,能够改善PVC膜的亲水性和疏油性,增大PVC膜的纯水通量,并实现了较高的截留率.当添加质量分数为40%的含氟聚合物时,PVC/FPEG(COOH)共混膜的水接触角为58.4°,油接触角为61.8°,纯水通量达226.5 L/(m2·h),其对正十六烷的截留率高达96.7%.%A fluorinated carboxylic polymeric additive,perfluoroalkyl polyethylene glycol acetic acid (FPEG(COOH)) has been synthesized,and fabricated into blended membranes with polyvinyl chloride (PVC).The effects of the additive on the membrane structure,surface properties,mechanical strength,pure water flux and separation efficiency were investigated by varying the composition of the coagulation bath,the concentration of polymer in the casting solution and the content of additive.Infrared spectroscopy (FT-IR),X ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) were also used to characterize the surface chemical composition and physical structure morphology of the prepared membranes.The results indicated that the addition of the fluorinated polymer FPEG(COOH) can improve both hydrophilic and oleophobic surface properties of the PVC membrane,and increase its pure water flux,whilst a high retention was also achieved.When a 40% loading of the fluorinated polymer was added to the mixture,the water contact angle of the resulting blended PVC/FPEG(COOH) membrane was 58.4°,the oil contact angle was 61.8°,and the pure water flux reached 226.5 L/(m2 · h),with its retention to n-hexadecane as high as 96.7 %.