English Abstract

Dispersion of Silica Particles in Rubber During Elongation Revealed by Ultra Small Angle X-ray Scattering and Reverse Monte Carlo Modelling

Tomotaka NAKATANI *1
Shinji KOHARA *1 *2
Taiki HOSHINO *1
So FUJINAMI *1
Masaki TAKATA *1 *3
*1:RIKEN SPring-8 Center, Sayo-gun, Hyogo, Japan
*2:National Institute for Materials Science, Sayo-gun, Hyogo, Japan
*3:Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai, Miyagi, Japan
Nippon Gomu Kyokaishi,(2019),92(4),152-157 General Review in Japanese

We analyzed the distribution of silica particles dispersed in an elastomer under deformation by reverse Monte Carlo (RMC) modelling. Using our RMC code, we can analyze a large system with many particles on a desktop PC. The code is effective for analyzing a system having a hierarchical structure like a rubber material. Ultra small angle X-ray scattering (USAXS) measurements under elongation by a bulge tester were performed on a silica-filled elastomer. The RMC modelling of USAXS data revealed the modification of the particle distribution in three dimensions. It was observed in the unstretched state that large sparse and dense parts formed, in terms of the particle dispersion, while these distinct regions disappeared on elongation. Furthermore, pair distribution function and interparticle angular distribution suggested that the dense regions show a structural order similar to a liquid metal, and that this ordering decreases due to elongation.

Keywords: Ultra Small Angle X-ray Scattering (USAXS), Bulge Tester, Reverse Monte Carlo Modeling, Silica Particle