Study on structures, dynamics and mechanical properties of styrene butadiene rubber (SBR)/silica interfaces: A fully atomistic molecular dynamics

Abstract

The interfacial mechanism has always been a concern for silica reinforced rubber nanocomposites, which are widely used in green tires. In this work, the relationship between the structures and mechanical properties at the interface of silica/SBR was investigated via all-atom molecular dynamics simulation. The results illustrated that different grafting fractions of the KH550 influence the inter- and intramolecular interactions between SBR/silica, which affects the amount of adsorbed chains on the filler surface, the number and length of trains, loops and tails, the flexibility of the bulk and the mechanical behavior of the interfacial deformation. Especially, the introduction of the chemical bonding increases the interfacial tensile strength to 760 MPa at 300K, which is 4 times that of the system without any modifications. Meanwhile, the chemical bonding reduces the differences of the structure between the interface and the bulk, together with the anisotropy of the system.