Study Of PLA/PMMA/SiO₂ Degradable Hybrid Polymer Solid Electrolytes

To aim at solving inorganic particles aggregate and environmental pollution of inorganic/polymer electrolytes, basing on sol-gel method, degradable PLA/PMMA/SiO2 hybrid polymer solid electrolyte was prepared, electrical and degradation properties of the hybrid polymer solid electrolytes were investigated, and the structure of relative products were characterized.PLA/PMMA/SiO2 hybrid materials were prepared from tetraethyl orthosilicate (TEOS), polylactic acid (PLA) and methyl methacrylate (MMA), with 3-methacryloxypropyl -trimethoxysilane(KH570) as silane coupling agent. The preparation paratmers were optimized, and the relative products were characterized and tested by FT-IR, XPS, DSC, XRD. The results indicated that SiO2 combined with PLA and MMA by Si-O-C, and PLA/PMMA/SiO2 hybrid material was amorphous, which contribute to better lithium ion transfer and goog degradability.Degradable PLA/PMMA/SiO2 hybrid polymer solid electrolyte was prepared by adding LiClO4 into PLA/PMMA/SiO2 hybrid matrix. The ionic conductivities of PLA/PMMA/SiO2 was 10-3~10-4 S/cm at room temperature, which were significantly improved with the increase of SiO2 or the increase of LiClO4, but when SiO2 content exceeded a certain value, the ionic conductivity was decreased; when LiClO4 content exceeded a certain value, the ionic conductivity increased unobviously.The electrochemical window of the electrolytes indicated that PLA/PMMA/SiO2 polymer solid electrolyte can meet the application needs of lithium-ion batteries.Degradable experiment for PLA/PMMA/SiO2 polymer solid electrolytes were conducted in borate buffer solution (pH=8.9) and natural soil, the result show polymer solid electrolytes degraded better in natural soil.