原位合成法制备高通量聚砜超滤膜及其性能研究

Preparation and performance of high-flux polysulfone ultrafiltration membrane by in-situ synthesis

以聚砜(PSF)为原料,N,N‐二甲基甲酰胺(DMF)为溶剂,4,4'-二氨基二苯砜(DDS)和均苯四甲酸二酐(PMDA)为添加物,在聚砜铸膜液中“原位合成”聚酰胺酸(PAA),采用浸没沉淀相转化法制备高水通量PSF超滤膜。使用傅里叶变换红外光谱仪(ATR-FTIR)和X射线光电子能谱分析(XPS)对膜表面化学组成进行分析,结果表明成功在膜表面引入PAA。膜的荷电性、水接触角、保湿性和水通量等性能测试表明,改性膜具有良好的保湿性和水渗透性。在0.1 MPa的运行压力下,改性膜的纯水通量和牛血清白蛋白(BSA)截留率均高于纯PSF超滤膜,纯水通量从221.39 L/(m^(2)·h)增加至406.57 L/(m^(2)·h),截留率从75.75%增加到96.14%;在0.01~0.1 MPa的运行压力范围内,改性膜水通量均高于纯PSF超滤膜。。

The polysulfone(PSF)ultrafiltration membranes were prepared with PSF raw material,N,N‐dimethylformamide(DMF),4,4'-diaminodiphenyl sulfone(DDS)and pyromellitic dianhydride(PMDA)through the method of immersion precipitation phase inversion.Among them,DDS and PMDA were doped into the casting solution of PSF to synthesize polyamic acid(PAA)via“in-situ synthesis”method.The fourier transform infrared spectrometer(ATR-FTIR)and X-ray photoelectron spectroscopy(XPS)were used to analyze the chemical composition of the membrane surface,and the results showed that PAA was successfully introduced into the membrane surface.Performance tests of the membrane􀆳s chargeability,water contact angle,moisture retention performance and water flux show that the modified membrane has great moisture retention and water permeability.Under 0.1 MPa operating pressure,the pure water flux and bovine serum albumin(BSA)rejection rate of the modified membrane are higher than that of the pure PSF membrane.The pure water flux increased from 221.39 L/(m^(2)·h)to 406.57 L/(m^(2)·h),and the BSA rejection rate increased from 75.75%to 96.14%.With the operating pressure range of 0.01~0.1 MPa,the water flux of the modified membrane is higher than that of pure PSF membrane.