界面增强型PVDF/PET膜的制备及性能

通过对支撑材料进行表面改性处理和浸入凝胶法制备了界面增强型聚偏氟乙烯/聚对苯二甲酸乙二醇酯（PVDF/PET）超滤膜。用电导率在线测量法确定了硅烷偶联剂 3-氨丙基三乙氧基硅烷（KH550）水解液的制备条件，考察了改性处理条件对PVDF/PET膜的界面性能和力学性能的影响。通过180°剥离试验测试PVDF膜与支撑层间的剥离强度，用扫描电镜观察PET无纺布及PVDF膜破坏底面的微观形貌，用傅里叶红外光谱仪表征PET表面化学组成。结果表明，水解液中KH550用量较少时（≤3%），处理时间延长，PVDF/PET间的剥离强度增大，水解液中KH550用量较多时（>3%），处理时间延长，PVDF/PET间的剥离强度先增大后减小；PVDF/PET膜的拉伸强度随水解液中KH550用量的增加或处理时间的延长先增大后略减小。改性前后PVDF/PET膜的分离与透过性能对比表明，PET表面改性后，PVDF膜的牛血清白蛋白（BSA）截留率几乎不受影响，水通量略增。

Preparation and properties of interface enhanced PVDF/PET membrane

An interface-enhanced PVDF/PET ultrafiltration membrane was successfully prepared by immersion precipitation using a surface modified PET nonwoven as support material. The preparation conditions of the silane coupling agent KH550 (3-aminopropyltriethoxysilane) hydrolyzate were obtained via on-line conductivity measurement. The effects of the modification conditions on the interfacial and mechanical properties of the PVDF/PET membrane were investigated in this work. The peel strength, surface micro-morphology and chemical composition of the prepared membrane were characterized by the 180°-peel test, SEM and FTIR, respectively. When KH550 content in the hydrolysate was less than 3%, the peel strength between the PVDF and PET increased with increasing treatment time. While KH550 content in the hydrolysate was higher than 3%, the peel strength between PVDF and PET increased firstly and then decreased slightly with increasing treatment time. Furthermore, with increasing KH550 concentration or treatment time, the tensile strength of PVDF / PET membrane showed a “volcanic” trend. The separation and permeation test results indicated that the rejection of bovine serum albumin (BSA) in PVDF membrane was almost constant and the water flux increased slightly after modification the PET surface.