Molecular Dynamics Simulations of Motional Coherency and Spatial Correlation of Amorphous Polymers

摘要

@@IntroductionThe static and dynamic properties of amorphous polymers at the glass transition have been investigated.As the temperature of the system is approached to the glass transition temperature (Tg), molecules are localizedand relaxation times increase by many orders of magnitude indicating a broad distribution. Cooperative motionis one of the keys to understand the dynamical behavior near Tg. However, the future of cooperative motion hasnot been fully understood. The de Gennes narrowing which is an example of motional coherency has beenobserved in amorphous materials such as polybutadiene (PB). [1,2] MD simulation is a powerful technique forstudying dynamic property at atomic level. In this study, we performed MD simulations of PB and poly(methylmethacrylate) (PMMA) molecules in bulk amorphous phase. Motional coherency and spatial correlation of PBand PMMA were investigated by analyzing the intermediate scattering functions.