利用前驱体水解聚合法制备的杂化膜的力学性能有较大提高,膜的透过和截留性能亦有较大改变,采用红外、DSC、TG和电镜等手段分析引起聚偏氟乙烯(PVDF)-硅杂化膜性能变化的原因,实验用的前躯体为正硅酸乙酯(TEOS).TEOS加入到PVDF铸膜液中以后,杂化后膜的热分解温度上升了20℃,膜断面结构由指状向海绵状变化,这些都有利于膜机械性能的改善.但TEOS对PVDF的结晶度影响很小,PVDF的β晶形有所减弱.同时由于膜液中TEOS的存在,导致膜表面孔增大,膜的截留性能持续降低.
This paper is the continuation of a new method of preparing enhanced organic - inorganic hybrid membranes. The method to prepare organic - inorganic hybrid membranes and the changes of the ultrafiltration and mechanical performance of the hybrid membranes were described in the anterior paper. This paper will analyze the reason of the changes of the ultrafiltration and mechanical performance of the hybrid membranes. Analysis shows: with the increase in TEOS content, the hybrid membrane' average gelatin rate basically shows firstly slower and then faster trend, the structure of the membrane goes through the process from dense to loose, all these are the uppermost reason that led to the changes of ultrafiltration and mechanical properties of membranes.