Strong Interface and High Dispersion of Silica Engineered by Polydopamine and Epoxidized Elastomer

ABSTRACT In the tire industry, silica is gradually replacing carbon black as a filler. However, silica has poor dispersibility in rubber and weak interfacial interactions with the matrix. Traditional silane coupling agents used to modify silica generate volatile organic compounds (VOCs). To address these challenges, this study first coated silica with polydopamine to provide an organic grafting platform for subsequent reactions, and then graft‐modified it using epoxidized solution‐polymerized styrene‐butadiene rubber (ESSBR). In this study, SiO 2 @ESSBR organic hybrid materials were prepared, and silica‐filled rubber composites without silane coupling agents were fabricated using wet mixing technology. The effects of ESSBR on the properties of the rubber composites were investigated. The results show that ESSBR was successfully grafted onto the polydopamine‐modified silica surface through covalent bonds, enhancing the interfacial interactions between the filler and the rubber matrix while improving hydrophobicity and dispersibility. With an increase in the grafting amount of ESSBR, the tensile strength and tear strength of the rubber composites improved, the Payne effect weakened, rolling resistance decreased, and wet skid resistance enhanced. Compared to ESBR/SiO 2 composites, the tensile strength, tear resistance, and wet skid resistance increased by 43.9%, 24%, and 27%, respectively, while rolling resistance decreased by 7.31%. This study provides an effective strategy for designing high‐performance rubber materials for environmentally friendly green tire treads.