Mechanical and Damping Properties Analyses of Small Molecular Modifiers/Nitrile-Butadiene Rubber Composite: Molecular Dynamics Simulation

Abstract

Nitrile-butadiene rubber (NBR) has been wildly applied in vibration control technology, it is usually mixed with organic small molecular modifiers and well vulcanized, which can greatly enhance the mechanical and damping properties of the material. This work aims to design the optimum blending ratio of hindered phenol A/B/NBR composite with the best damping property by means of molecular dynamics (MD) simulation, and investigate the mechanical performance from the molecular level. The shear deformation simulation is conducted on pure NBR models to study the impact of rubber crosslink degree (CD) on elasticity and plasticity of NBR. To research the damping mechanism of the material, detailed analyses of the micro molecular structure and reciprocating shear simulation are carried out on NBR composite models with different hindered phenol A/B ratio. The simulation results indicate a strong positive correlation between intermolecular H-bonds and loss factor η, and the NBR composite with hindered phenol A/B per hundred rubber (phr) 30/30 shows the best damping performance.