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Local Structure and Dynamics of Trans-polyisoprene oligomers

Roland Faller·Florian Mueller-Plathe·Manolis Doxastakis·Doros Theodorou
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Abstract

Mono- and poly-disperse melts of oligomers (average length 10 monomers) of trans-1,4-polyisoprene are simulated in full atomistic detail. The force-field is developed by means of a mixture of ab initio quantum-chemistry and an automatic generation of empirical parameters. Comparisons to NMR and scattering experiments validate the model. The local reorientation dynamics shows that for C$-$H vectors there is a two-stage process consisting of an initial decay and a late-stage decorrelation originating from overall reorientation. The atomistic model can be successfully mapped onto a simple model including only beads for the monomers with bond springs and bond angle potentials. End-bridging Monte Carlo as an equilibration stage and molecular dynamics as the subsequent simulation method together prove to be a useful method for polymer simulations.

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Roland Faller, Florian Mueller-Plathe, Manolis Doxastakis, Doros Theodorou. 2000-12-20. Local Structure and Dynamics of Trans-polyisoprene oligomers. https://doi.org/10.1021/ma0016782

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