以甲氧基聚乙二醇甲基丙烯酸酯(MPEGM)和十六烷基聚乙二醇甲基丙烯酸酯(HPEGM)为单体,采用自由基溶液聚合法制备无规接枝共聚物P(MPEGM—HPEGM),并以此共聚物为基体混合锂盐(LiClO4)制备全固态聚合物电解质。用红外光谱(Fr—IR)、差热分析(DSC)和交流阻抗(EIS)等方法对聚合物和聚合物电解质的性能进行研究。结果表明:MPEGM和HPEGM共聚生成P(MPEGM—HPEGM);聚合物中聚氧化乙烯(PEO)链段的运动能力得到提高,有利于离子传输;聚合物电解质膜的电化学稳定性窗口达到4.5V;在30℃时,当MPEGM与HPEGM的质量比为80:20,锂盐与氧化乙烯(EO)的摩尔比为1:20时,聚合物电解质的离子电导率达到最高7.6×10^-3/cm;离子电导率随着温度的升高而迅速增加,电导率一温度的关系符合VTF方程。
A novel graft copolymer P(MPEGM-HPEGM) was prepared by co-polymerizing of two macro- monomers : methoxy-poly ( ethylene glycol) methaerylate (MPEGM) and hexadecal-poly ( ethylene glycol) methaerylate (HPEGM). And the polymer electrolytes were prepared by blending P(MPEGM-HPEGM) and LiC104. The performances of the polymer and polymer electrolytes were studied by Fourier transform infrared spectrometry ( FT-IR ), differential scanning calorimetry ( DSC ) and electrochemical impedance spectroscopy (EIS). The results showed that P (MPEGM-HPEGM) was successfully synthesized and the motion of poly ( ethylene oxide) (PEO) chains was improved. The electrochemical stability of the polymer electrolytes was up to 4. 5 V. When the weight ratio of MPEGM to HPEGM was 80:20 and the mole ratio of lithium salt to ethylene oxide (EO) was 1: 20, the maximum ionic conductivity reached 7.6×10^-3S/cm at 30 ℃. The temperature dependence of ionic conductivity of solid polymer electrolytes appeared to obey Vogel-Tamma-Fuleher (VTF) equation.