Constructing Chemical Interface Layers by Using Ionic Liquid in Graphene Oxide/Rubber Composites to Achieve High-Wear Resistance in Environmental-Friendly Green Tires

The harm caused by small rubber particles generated from tire abrasion to the atmosphere is receiving a continuing concern. For developing environmental-friendly tire tread materials with high wear resistance, building the strong interface between nano-fillers and rubber matrix is the primary challenge. Herein, ionic liquid (IL, 1-allyl-3-methylimidazole chloride) was used to modify graphene oxide (GO) by π-cation interaction and hydrogen bonding between IL and GO. Furthermore, an IL-GO/natural rubber (NR) masterbatch possessing fine dispersion of GO was prepared by the emulsion compounding method, and thereafter, a further compound with solution polymerized styrene butadiene rubber (SSBR) was fabricated for the tread rubber composite. Results showed that the double bond in the IL enhanced the cross-linking reaction during the vulcanization of rubber composites occurred at high temperature, leading to an elevated interfacial interaction between the IL-modified GO and the rubber macromolecules. Compared with silicon dioxide (SiO₂)-filled NR/SSBR composites, the cross-link density, 300% modulus, and tear strength of the IL-GO/SiO₂/NR/SSBR composites were increased by 10.2, 42.6, and 20.2%, respectively. Importantly, the wear resistance of the IL-GO/SiO₂/NR/SSBR composites was improved by 17.3%, ascribing to the strong interface between IL-GO and rubber macromolecules.