聚合物固体电解质中的离子状态与导电机理的研究

制备得到了一种新颖的聚氨酯和丙烯酸酯复合梳形交联聚合物 (Combcross linkedpolymer) ,并以此聚合物为基体加入不同含量的高氯酸锂盐制得一系列聚合物固体电解质 ,其室温电导率可以达到 3 4× 10 - 5S·cm- 1 .通过Raman、DSC、SEM及电性能等研究了电解质中的盐浓度与离子存在状态及离子电导率之间的关系 .结果显示随着盐浓度的增加 ,聚合物固体电解质中离子对的比例和电导率都迅速增加 ,说明离子对 (由多个醚氧原子、阴离子和阳离子组成 )对体系导电起着积极的作用 .

STUDIES ON THE ION STATES AND ION TRANSPORT MECHANISM OF SOLID POLYMER ELECTROLYTES

A series of new solid polymer electrolytes (SPE) were prepared based on polyurethane/acrylate comb cross-linked polymers.The ionic conductivity of the electrolytes could reach 3.4×10 -5 S·cm -1 at 25℃.Raman spectroscopy,DSC,SEM and conductivity measurement were used to study interrelations among salt concentration,ion states and ionic conductivity.In solid polymer electrolytes with high salt concentrations,it was considered that the ion pairs may play an important role in ion transport.When the salt content was low,the free ion was the main form of salt in the electrolytes.The content of ion pairs increased with increasing the salt content.The ion pair became an important form of salt in the electrolyte when the salt content was high,and the ionic conductivity increased greatly in a certain range.Under these conditions,the ion pairs should act as an active entity in the ionic conduction of the electrolytes.When the SPE films were in atmosphere,the ions were unstable,and they would congregate and form crystallinites.Proper conditions could keep the ion stability of the polymer electrolyte films.