液晶离聚物蒙脱土掺杂PMMA/PEO电解质膜的性能

Performance of liquid crystal ionomer-montmorillonite doped PMMA/PEO electrolyte membranes

为了解决聚环氧乙烷作为聚合物电解质基体在室温下电导率低的问题,采用由液晶离聚物插层蒙脱土(LCT)制成的层状硅酸盐纳米复合材料作为功能性掺杂剂,采用自动刮膜技术制备液晶离聚物蒙脱土掺杂PMMA/PEO聚合物电解质膜.结果表明:掺杂0.5%LCT的PMMA/PEO电解质中PEO结晶度最低为25.0%;掺杂1.5%LCT的PMMA/PEO电解质的初始分解温度由157.4℃提高到212.0℃;添加2.5%LCT的电解质膜表面最平整,几乎没有孔洞;添加0.5%LCT后电解质的电导率由1.12×10^(-5) S/cm提高到3.26×10^(-5) S/cm,提高了约2倍;添加1.5%LCT后电解质拉伸强度提高到6.43 MPa,添加0.5%LCT后电解质的断裂伸长率提高到883%.LCT的加入有利于PMMA/PEO聚合物电解质膜电性能、热性能和力学性能的提高.

In order to improve the low electrical conductivity of polyethylene oxide(PEO)as polymer electrolyte matrix at room temperature,a layered silicate nanocomposite prepared by liquid crystal ionomer intercalated montmorillonites(LCT)was used as a functional dopant,and LCT-doped PMMA/PEO electrolyte membranes were prepared by an automatic film scraping technology.The results show that the PEO crystallinity of PMMA/PEO electrolyte doped with 0.5%LCT is at least 25.0%.The initial decomposition temperature of PMMA/PEO electrolyte doped with 1.5%LCT increases from 157.4℃to 212.0℃.The surface of electrolyte membrane with 2.5%LCT is the smoothest and has almost no holes.The conductivity of electrolyte increases from 1.12×10^(-5) S/cm to 3.26×10^(-5) S/cm,improving by 2 times after adding 0.5%LCT.After the addition of 1.5%LCT,the tensile strength of electrolyte increases to 6.43 MPa,and the elongation of electrolyte increases to 883%by adding 0.5%LCT.The addition of LCT is beneficial to improving the electrical,thermal and mechanical properties of PMMA/PEO polymer electrolyte membranes.