TITLE

Simulation of crystallization of entangled polymer chains

AUTHOR(S)
Xu, Liang; Fan, Zhongyong; Zhang, Hongdong; Bu, Haishan
PUB. DATE
October 2002
SOURCE
Journal of Chemical Physics;10/1/2002, Vol. 117 Issue 13, p6331
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
The crystallization of entangled polymer chains is studied by three-dimensional Monte Carlo simulations using the bond fluctuation model. To simulate entanglement, a mobile chain is assumed to move in a frozen environment through fixed obstacles. Simulation indicates that the temperature scale can be divided into three regions. In region I, high supercooling, the crystallization rate is high while disentanglement rate is low. In region III, low supercooling, the crystallization rate is much lower compared with disentanglement. Both rates can match each other in region II. Simulation also shows different morphologies in different temperature regions. In the simulation, all chains are mobile, but entanglement may still exist due to a high concentration of monomers. A new layer of crystal is observed to form on the surface of the seed at higher temperature, while chains crystallize in situ without large-scale movement at lower temperature. In moderate temperature range, disentanglement could match crystallization, and the new layer of crystal could still form on the seed but with smaller thickness. By close observation, the new layer of crystal consists of more than one chain when crystallization forms at higher supercooling because the crystallization rate is high in this case; a new chain deposits on the seed and crystallizes before the completion of crystallization of the former attached chain.
ACCESSION #
7337051

 

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