关键词: 纳米SiO2, 聚合物电解质, 离子电导率, 玻璃化温度, 结晶

Abstract: Nano-silicon oxide was doped into a novel comblike polyether,poly(3-(methoxy(triethylenoxy))methyl-3'-methyloxetane) to prepare a series of composite polymer electrolyte.The ion conductivity measurement revealed that the composite polymer electrolyte added with 5% weight fraction of SiO2 has the highest ion conductivity of 7.8×10-5 S/cm at 30℃ and 4.5×10-4 S/cm at 80℃,which is increased 30%~60% as compared to the polymer electrolyte without adding any SiO2.DSC results implied that the nano-silicon oxide inserts into the macromolecule chains to increase the free volume and decrease the glass transition temperature to enhance the ion conductivity.In addition,it seems that the crystallization occurred due to the hydrogen bonds between hydroxyl group on the surface of silicon oxide and oxygen atoms on the polymer chains.And XRD spectrum demonstrated the existence of micro-crystals.The heat decomposition temperature was detected by TGA,indicating the good heat stability of this composite polymer electrolyte.

Key words: nano SiO2, polymer electrolyte, ion conductivity, glass transition temperature, crystallization