In the present paper, epoxidized solution-polymerized styrene–butadiene (ESSBR) is successfully synthesized through an epoxidation reaction with hydrogen peroxide and formic acid aiming to improve the performance of silica/SSBR nanocomposites without a silane coupling agent (SCA). A safer and milder reaction condition of H2O2/C = C/HCOOH (0.36/2/0.6) is obtained. The silica/ESSBR nanocomposites are prepared by grafting silica nanoparticles on the ESSBR matrix, and the influence of various epoxidation degrees on the structure and performance is investigated. The silica/ESSBR with epoxidation degree 13.8% (silica/ESSBR13.8) shows excellent comprehensive performance on account of the potent interfacial interaction and a uniform dispersion of silica nanoparticles. Compared with the silica/SSBR nanocomposite using Si69 as the SCA (silica/SSBR-Si69), silica/ESSBR13.8 enhances the modulus at 300% strain by 46.8%, reinforcing index by 29.1%, wet-skid resistance by 80.8%, and abrasion resistance by 32.8%. The silica/ESSBR nanocomposites are environmentally friendly and have potential applications in green tires.

In this paper, ternary silicone dielectric elastomer micro‐nanocomposites were prepared by mixing barium titanate (BT) nanoparticles or 3‐mercaptopropylethoxy‐bis(tridecyl‐pentaethoxy‐siloxane) (Si747)‐modified BT (BT‐Si747) with hexagonal boron nitride (BN) microplatelets into methyl vinyl silicone rubber (MVSR). BN platelets as physical barriers improve the dispersion of BT nanoparticles, so the MVSR/BT/BN composites achieve the higher electric breakdown field. The Si747 in MVSR/BT‐Si747/BN composites can be grafted on BT nanoparticles surface while the mercapto groups of Si747 can react with double bonds of MVSR, which increases interfacial interaction to improve the mechanical property. As a result, the tensile strength and elongation at break of MVSR/30 wt%BT‐Si747/30 wt%BN composite are 3.43 MPa and 2705%, which is 2.4 and 4.4 times as high as the MVSR/30 wt%BT/30 wt%BN composite, respectively. The MVSR/BT‐Si747/BN composites exhibit higher actuation performance under lower electric fields due to simultaneous increase in dielectric constant and decrease in elastic modulus. The MVSR/10 wt%BT‐Si747/10 wt%BN composite obtains an actuated strain of 8.81% at 47.48 kV/mm, which is twice as high as pure MVSR (4.4% at 60.21 kV/mm). The used method in this experiment is simple, effective, and low cost, and prepared ternary micro‐nanocomposites have potential applications in dielectric actuators.