高等学校化学学报2024，Vol.45Issue(6)：131-142,12.DOI:10.7503/cjcu20240013
遥爪型聚丙二醇熔体动力学的宽频介电谱研究
Broadband Dielectric Spectroscopy Study of Dynamics of Telechelic Polypropylene Glycol Melts
摘要
Abstract
Excellent polymer electrolytes require a combination of high ionic conductivity and mechanical strengths.An in-depth understanding of the relationship between polymers'microscopic structure and dynamics and macrosco-pic conductive and mechanical properties is essential for the molecular design of high-performance polymer electro-lytes.In the present paper,we selected low temperature of glass transition(Tg)and non-crystalline telechelic polypro-pylene glycol melts as a model system to investigate the molecular dynamics of associating polymers.Allyl-terminated polypropylene glycols having molecular weights of 1000,2000 and 4000 were synthesized by chemically modifying the end groups,and the influence of chain-end interaction strength and molecular weight on their multi-scale dyna-mics was investigated using broadband dielectric spectroscopy.The polypropylene glycols with two different end groups exhibit both the α-relaxation associated with the segmental motion and the normal mode relaxation associated with the global motion of the chain.End group interactions influence both two relaxations;stronger interactions lead to longer relaxation time at the same temperature.This effect becomes more pronounced for the lower-molecular-weight samples,because the motion has been suppressed for the denser end groups therein.The generalized entropy theory was utilized to study the glass formation of telechelic polymer melts having variable sticky interaction strength and molecular mass,and theoretical predictions were shown to be in qualitative agreement with experimental results.These dynamic details can be used in guiding the molecular design of polymer electrolytes.关键词
遥爪型高分子/玻璃化/介电谱/熵理论Key words
Telechelic polymer/Glass formation/Dielectric spectroscopy/Entropy theory分类
化学化工引用本文复制引用
白蓉,李尚伟,陈全,孙昭艳,徐文生..遥爪型聚丙二醇熔体动力学的宽频介电谱研究[J].高等学校化学学报,2024,45(6):131-142,12.基金项目
国家自然科学基金(批准号:22222307,21973089,52203029)和中国博士后科学基金(批准号:2022M713069,YJ20210403)资助. Supported by the National Natural Science Foundation of China(Nos.22222307,21973089,52203029)and the China Postdoctoral Science Foundation(Nos.2022M713069,YJ20210403). （批准号:22222307,21973089,52203029）
