Molecular Dynamics Studies on Polymer Crystallization from a Stretched Amorphous State

Polymer crystallization from a uniaxially stretched amorphous state was investigated by molecular dynamics simulation using a realistic molecular model of poly(ethylene). Simulations for crystallization were performed at temperatures between 280 and 350 K. Structure formations to crystalline states having lower symmetries than the hexagonal phase of poly(ethylene) were realized above 300 K. It was found that all of the order parameters considered to analyze the crystallization process showed the same time dependence at a given temperature: there was no precursor prior to crystallization. The temperature dependence of the crystallization rate has a bell-shape, and a maximum of the crystallization rate appears around 325 K.