Statics,Dynamics and Linear Viscoelasticity from Dissipative Particle Dynamics Simulation of Entangled Linear Polymer Melts  

作　　者：Fan Wang Lu-Kun Feng Ye-Di Li Hong-Xia Guo 

机构地区：[1]Beijing National Laboratory for Molecular Sciences,Joint Laboratory of Polymer Sciences and Materials,State Key Laboratory of Polymer Physics and Chemistry,Institute of Chemistry,Chinese Academy of Sciences,Beijing,100190,China [2]University of Chinese Academy of Sciences,Beijing,100049,China

出　　处：《Chinese Journal of Polymer Science》2023年第9期1392-1409,I0007,共19页高分子科学（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Nos.21790343,21574142 and 21174154);the National Key Research and Development Program of China(No.2016YFB1100800)。

摘　　要：Dissipative particle dynamics(DPD)with bond uncrossability shows a great potential in studying entangled polymers,however relatively little is known of applicability range of entangled DPD model to be use as a model for ideal chains and properly describe the full dynamics of entangled melts.Therefore,we perform a comprehensive study on structure,dynamics and linear viscoelasticity of a typical DPD entangled model system,semiflexible linear polymer melt.These polymers obey Flory's ideality hypothesis in chain dimensions,but their local structure exhibits nonideal behavior due to weak correlated hole effect.Both monomer motion and viscoelasticity relaxation reproduce the full pictures as predicted by reptation theory.The stronger chain length dependent diffusion coefficient and relaxation time as well as dynamic moduli are in close agreement with predictions of modern tube model that accounts for additional relaxation mechanisms besides chain reptation.However,an anomalous sub-diffusive center of mass motion is observed both before and after the intermediate reptation regime and the cross-correlation between chains is not negligible even these polymers obey stress-optical law,indicating limitations of the reptation theory.Hence semiflexible linear entangled DPD model can correctly describe statics and dynamics of entangled polymer melts.

关 键 词：Entangled polymer melts DYNAMICS Linear viscoelasticity Dissipative particle dynamics 

分 类 号：TQ317[化学工程—高聚物工业]