A Monte Carlo study of the glass transition of polymethylene

Citation
Lx. Zhang et al., A Monte Carlo study of the glass transition of polymethylene, CHIN J POLY, 17(6), 1999, pp. 543-549
Citations number
28
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Organic Chemistry/Polymer Science
Journal title
CHINESE JOURNAL OF POLYMER SCIENCE
ISSN journal
0256-7679 → ACNP
Volume
17
Issue
6
Year of publication
1999
Pages
543 - 549
Database
ISI
SICI code
0256-7679(1999)17:6<543:AMCSOT>2.0.ZU;2-3
Abstract
By this Monte Carlo simulation we studied the glass transition of polymethy lene using the modified bond-fluctuation model combined with considering th e rotational-isomeric state model. The configurational properties in the po lymethylene (PM) melts, such as the mean length, the mean energy per bond a nd the mean square radius of gyration were monitored. We found that the cha ins cannot be in the equilibrium states after a very long time when the tem perature of the dense PM chains decreases to 120 K. As the melt vitrifies, these quantities gradually become independent of temperature in a narrow ra nge. The glass transition temperature T-g depends upon the chain length of PM chains, and extrapolation to (CH2)(infinity) gives T-g(infinity) = 212 K . The dynamics in the PM melts was also studied. It was found that the diff usion coefficients can be described by the Vogel-Fulcher law and the Vogel- Fulcher temperature T-0 is 124 K. This method may be used to investigate th e glass transition of other real polymer chains.