English Abstract

General Techniques of Coarse-grained Molecular Dynamics Simulation for Rubber Materials

Hiroshi MORITA
National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan
Nippon Gomu Kyokaishi,(2016),89(6),157-163 General Review in Japanese

In this manuscript, the generic technology of coarse-grained molecular dynamics (CGMD) simulation method and its applications for rubber materials are reviewed. First, fundamental coarse-grained technique is explained and the limitations of those models are also indicated, which will be much important for the application studies. As a typical example of coarse-grained simulation model, Kremer-Grest model is sometimes used. To perform the simulation using Kremer-Grest model, the construction of the initial structure is one of the most important steps and the fully relaxed structures must be needed to eliminate the local structure having residual stress. As examples of CGMD simulations, uniaxial elongation simulation of pure rubber system, rheological simulation of nano-rubber particle, and the elongation simulation of filler filled materials are explained. In the elongation simulation of pure rubber, the stress-strain curve obtained by CGMD simulation is explained, having entropic and energetic effects of elasticity. From the rheological simulations, G', G", and tanδ can be measured. In the elongation simulation of filler filled rubbers, the simulation results using the Poisson's ratio of 0.5 and 0.0 are shown. From these simulations, the applicability of CGMD simulation is explained. The author hopes the increase of the examples of application studies and expects further understanding of rubber materials by CGMD simulations.

Keywords: OCTA, Coarse-grained Molecular Dynamics Simulation, Uniaxial Elongation Simulation, Rheological Simulation, Filler Filled Rubber