凝固浴组成对 PVDF/TA-ATP 杂化膜成膜过程及膜性能的影响研究

摘要

In this work,attapulgite modified by tannic acid (TA),PVDF and porogen polyethylene glycol (PEG)were mixed and PVDF/TA-ATP flat sheet hybrid membrane was prepared by the method of phase in-version.The thermal properties and morphology of the hybrid membrane was characterized by differential scan-ning calorimetry and scanning electron microscopy,respectively.The effect of coagulation bath composition on the hybrid membrane in membrane-forming progress and then the pure water flux were studied by the method of thermodynamic phase diagram and ultrasonic reflection.The results showed that by adding more ethanol and DMF to the coagulation bath,more non-solvent was needed for phase separation,and the membrane-forming speed slowed significantly,the pore structure changed from finger-like pores with density skin into sponge-like pores without skin,the pure water flux increased.%将单宁酸(TA)改性的凹凸棒土(ATP)与聚偏氟乙烯(PVDF)和致孔剂聚乙二醇(PEG)混合,通过浸没沉淀相转化法制备了 PVDF/TA-ATP 杂化膜。利用差示扫描量热仪(DSC)和扫描电子显微镜(SEM)对杂化膜的热性能及微观形貌进行了表征,采用热力学相图和超声反射方法探讨了凝固浴组成对膜成膜过程的影响,进而研究了凝固浴组成对膜水通量的影响。研究结果表明,随着凝固浴中乙醇、N,N-二甲基甲酰胺(DMF)含量的增加,PVDF/TA-ATP 体系耐非溶剂能力增强,成膜速度减慢,膜孔结构由指状孔向海绵层结构渐变,纯水通量整体呈增大趋势。