ISSN:
1573-4900
Keywords:
Liquid-crystalline polymers
;
Molecular modelling
;
Microstructure
;
Lattice model
;
Shear
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Summary Liquid-crystalline polymers exhibit fascinating structure at many size scales. This paper describes how computer models at different size scales can be linked together by a hierarchical approach to give a better understanding of the properties and behaviour of these materials. The atomic scale is considered first, where semi-empirical molecular orbital techniques are used to calculate the torsional energy functions associated with rotating the backbone bonds of the polymer. Secondly, entire chains are simulated using a Monte Carlo technique based on the torsional energy functions to deduce the persistence length of the polymer of interest. A theoretical relationship enables the Frank elastic constants to be determined from the persistence length. The elastic constants may then be used as input parameters for models both to predict microstructure and to help understand the role of defects in the shear flow of these materials. The hierarchical approach provides a meaningful framework within which data obtained from small-scale models are used to parameterise models at a larger scale.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01185674
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