Probing Intermittent Motion of Polymer Chains in Weakly Attractive Nanocomposites  

作　　者：Li-Jun Dai Cui-Liu Fu You-Liang Zhu Zhan-Wei Li Zhao-Yan Sun 

机构地区：[1]State Key Laboratory of Polymer Physics and Chemistry,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China [2]University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Chinese Journal of Polymer Science》2020年第6期620-628,共9页高分子科学（英文版）

基　　金：the National Natural Science Foundation of China(Nos.21790344,21833008,21774129);the National Key R&D Program of China(No.2018YFB0703701);the Jilin Provincial science and technology development program(No.20190101021JH);the Key Research Program of Frontier Sciences,CAS(No.QYZDY-SSW-SLH027).

摘　　要：In this study,we investigate the motion of polymer segments in polymer/nanoparticle composites by varying nanoparticle(NP)volume fractions.By studying the probability distribution of segment displacement,segment trajectory,and the square displacement of segment,we find the intermittent motion of segments,accompanied with the coexistence of slow and fast segments in polymer nanocomposites(PNCs).The displacement distribution of segments exhibits an exponential tail,rather than a Gaussian form.The intermittent dynamics of chain segments is comprised of a long-range jump motion and a short-range localized motion,which is mediated by the weakly attractive interaction between NP and chain segment and the strong confinement induced by NPs.Meanwhile,the intermittent motion of chain segments can be described by the adsorption-desorption transition at low particle loading and confinement effect at high particle loading.These findings may provide important information for understanding the anomalous motion of polymer chains in the presence of NPs.

关 键 词：NANOCOMPOSITES INTERMITTENT dynamics The probability distribution of displacement CONFINEMENT ADSORPTION-DESORPTION mechanism 

分 类 号：TB33[一般工业技术—材料科学与工程]