Aminosilane modified graphene oxide for reinforcing nitrile butadiene rubber: Experiments and molecular dynamic simulations

Graphene oxide (GO) was chemically modified by 3-aminopropyl)triethoxysilane. The modified GO (denoted as MGO) was used to reinforce nitrile butadiene rubber (NBR). The occurrence of the chemical modification was confirmed by various characterization techniques. NBR/GO (or MGO) composites were prepared by a mechanical blending process. Their mechanical and tribological properties of NBR-GO/MGO nanocomposites were investigated. The NBR/MGO composites exhibited superior performances compared to their NBR/GO counterparts over the GO (or MGO) range of 1–5 wt%. The tensile strength of the NBR/MGO (1phr) was increased by 43.7% and 30.3%, and the abrasion loss was decreased by 59.3% and 58.9% with regard to the NBR and NBR/GO composite, respectively. The morphologies of the fractured and worn surfaces of the composites were characterized by scanning electron microscopy and energy dispersive X-ray spectroscopy to reveal the reinforcement mechanisms of MGO. The pull-out behavior of the GO or MGO from the NBR matrix and the interlayer peel-off behavior of the GO or MGO were described by molecular dynamic simulations. The stress required to pull the MGO off the NBR matrix was 121.2% that for the GO, while that of the interlayer peel-off for the MGO was 36.7% that for the GO. This explains the fact that the MGO was able to be better dispersed in the NBR than the GO and consequently better reinforce the mechanical and tribological properties of the latter.