改性硅藻土/聚偏氟乙烯-六氟丙烯共聚物插层结构多孔聚合物电解质的制备及电化学性能

Preparation and Electrochemical Performance of Porous Polymer Electrolyte Membrane with Modified Diatomite/P(VDF-HFP)Inserted Layer Structure

采用聚偏氟乙烯-六氟丙烯共聚物[P(VDF-HFP)]为基体,掺杂不同质量分数的表面改性硅藻土,通过浇铸-热压法制膜。利用扫描电镜、X射线衍射、热重-差示扫描量热法、交流阻抗法等测试手段对电解质膜的物理和电化学性能进行了表征与测试。实验表明,添加2%改性硅藻土的聚合物电解质膜相比于纯聚合物电解质膜的孔隙率、吸液率和热稳定性都有所提高,结晶度降低,界面稳定性极大改善,电导率(30℃)和电化学稳定窗口分别达2.90 mS/cm和5.5V。表明在聚合物基体中嵌入高开孔结构的硅藻土构成插层结构的方案具有取代造孔剂制膜方法的可能性。

A kind of poly（vinylidene fluoride-eo-hexafluoropropylene）-based composite polymer electrolyte doped with surface hydrophobie-modified diatomite was prepared by casting method. Physical and electrochemical properties of composite polymer membrane were tested by SEM, XRD, TG-DSC, EIS and LSV. Experiments show that , compared with the pure polymer electrolyte membrane, .the properties of porosity, electrolyte uptake and thermal stability of the polymer electrolyte membrane with 2% content of modified diatomite are effectively improved, the erystallinity decreases and the stability of interface is improved. In particular, the electrical conductivity （30 ℃ ） and electrochemical stability window of the eomtxxsite polymer membrane can reach 2.90 mS/em and 5.5 V respectively. It is proved that in the polymer matrix, the scheme of intercalating structure of diatomite with high opening structure is feasible to replace the pore-forming one.