Molecular simulation and experimental characterisation of monotropic and enantiotropic polymers containing azobenzene and diphenyl mesogens

Citation
D. Pavel et al., Molecular simulation and experimental characterisation of monotropic and enantiotropic polymers containing azobenzene and diphenyl mesogens, COMP TH POL, 11(4), 2001, pp. 303-318
Citations number
28
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Organic Chemistry/Polymer Science
Journal title
COMPUTATIONAL AND THEORETICAL POLYMER SCIENCE
ISSN journal
1089-3156 → ACNP
Volume
11
Issue
4
Year of publication
2001
Pages
303 - 318
Database
ISI
SICI code
1089-3156(2001)11:4<303:MSAECO>2.0.ZU;2-X
Abstract
Molecular simulation techniques have been applied to previously synthesised liquid crystalline polymers containing azobenzene and diphenyl mesogenic g roups within the chain. Single chains and amorphous unit cells of aromatic polymers with a degree of polymerisation of 4-16 and containing propylene a nd diethyletheric (oxydiethylene) spacers were used. The energy was minimis ed and then molecular dynamics were performed for 1000 ps at seven temperat ures between 10 and 600 K. The axial ratio or coefficient of asymmetry was calculated from computer-generated structures. The predictive capability of the orientational order parameter was used to estimate the degree of orien tation and the liquid crystalline-isotropic transition temperature of the p olymers. The simulated results for the monotropic polymers agreed very well with Maier-Saupe mean field theory and experimental data, though the enant iotropic polymer did not show a good agreement. The predicted glass transit ion and decomposition temperatures of the simulated polymers are also repor ted. (C) 2001 Elsevier Science Ltd. AU rights reserved.