纳米SiO_2复合的梳状聚醚聚合物电解质的导电性能研究

Studies on the Ion Conductive Performance of Composite Polymer Electrolyte Containing Nano-scale SiO_2

于含锂盐的梳状聚醚聚合物电解质添加纳米SiO2制备复合聚合物电解质，并分别使用DSC和XRD研究SiO2对聚合物链段运动能力的影响．电导率测试表明，在相同的锂盐浓度下，加入5％的纳米SiO2后，聚合物电解质具有最高的离子电导率，30℃时为7．8×10^-5S／cm，80℃时达到4．5×10^-4／cm．与未添加SiO2的聚合物电解质相比，电导率提高了30％～60％．TGA测定给出该聚合物的热分解温度为300℃左右，显示出良好的安全性能．

Nano-silicon oxide was doped into a novel comb-like 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^-5S/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.