含氟聚合物杂化电解质膜的结构分析

Study on the Structure of Fluoropolymer Hybrid Electrolytes

采用熔融辊压法和溶液浇铸 -浸渍法 ,制备了结构与性能不同的含液体电解质的聚偏氟乙烯 -六氟丙烯共聚物基杂化电解质 ,并考察了制膜方法对产物结构与性能的影响 .两种成膜法所制样品 ,在液体电解液的质量分数为 72 .5%时 ,室温电导率均超过 1× 1 0 - 3 S/cm,且电导率的差别与相应的结构有关 . XRD、SEM和 DSC的研究结果表明 :溶液浇铸 -浸渍法制备的样品中 ,聚合物基材呈微孔状 ,电解液对聚合物基材的结构改变较小 ,而熔融法所制样品中液体电解液对聚合物基材的结构改变较大 .恒温热重分析结果证明 ,熔融法制备的样品保液性能优于溶液浇铸 -浸渍法的样品 .

Hybrid polymer electrolytes were prepared from poly(vinylidene fluoride co hexafluoropropylene) and LiClO 4 by two methods: melting rolling method and solution casting impregnation method. Both two thus prepared hybrid polymeric electrolytes with the same electrolyte solution content, 72 5%(mass fraction) of 1 mol/L LiClO 4 in ethylene carbonate/propylene carbonate (1∶1 volume ratio), exhibited high ionic conductivity >1×10 -3 S/cm at room temperature. The XRD, SEM, DSC and TGA demonstrated that the first method gave homogeneous structure of polymeric electrolyte, in which the liquid electrolyte has great interaction with polymer matrix and the samples obtained by 2nd method are microporous, where liquid electrolyte solution shows less influence on the matrix structure. Samples prepared by the 1st method have better solution retention property than samples from 2nd method.