混合稀释剂对热致相分离法制备聚偏氟乙烯膜性质及结构的影响

Effect of mixed diluent on property and structure of PVDF membrane prepared via TIPS method

摘要:

采用邻苯二甲酸二丁酯(DBP)为稀释剂，通过加入部分良溶剂N，N二甲基乙酰胺（DMAc）或稀释剂邻苯二甲酸二辛酯(DOP)，分别在150℃和220℃下，采用热致相分离法制备了聚偏氟乙烯(PVDF)平板膜，研究了在较低温度下或高温下制得膜的性能和结构。结果显示：加入质量分数为10%的DMAc在150℃下制膜，比采用纯的DBP为稀释剂时膜的通量提高了28%，过多DMAc的加入反而会使膜的通量降低；加入质量分数为10%的DOP在220℃下制膜，膜的通量则下降了62%。同时采用扫描电镜观察了膜的截面结构，解释了采用不同混合稀释剂时膜形成不同结构的原因。

Abstract:

Polyvinylidene fluoride flat membranes are prepared via TIPS method by using DBP as diluent and DMAc or DOP as mixed diluent at 150℃ and 220℃ repectively. The water flux and structure of membrane prepared under lower and higher temperature are investigated. The result shows that water flux of membrane prepared with 10% DMAc addition at 150℃ is 28% higher than that prepared with DBP as diluent. water flux tends to decrease when the addition of DMAc is above 10%. Water flux of membrane prepared with 10% DOP addition at 220℃ is 62% lower than that prepared with DBP as diluent. At the same time, the structure of membrane is observed and the reason of formation of different structure is explained.