Preparation of “core-shell” structured SiO2@TiO2 nanospheres by in-situ polymerization and grafting modification method for enhancing fluororubber’s mechanical performance

To attain the high dispersion and strong interfacial bonding of TiO 2 in fluororubber (FKM), a novel “core–shell” structured SiO 2 @TiO 2 nanofillers was designed and synthesized by in-situ polymerization and grafting modification method. For the “core–shell” structured SiO 2 @TiO 2 nanospheres , the rough and irregular silica shell can improve the surface area of the SiO 2 @TiO 2 filler and realize the mechanical riveting with the FKM, which shows a significant mechanical properties enhancement function. Compared with the pristine FKM, the tear strength , tensile strength , hardness, modulus at 100% strain, modulus at 300% strain, and storage modulus at −100 °C of FKM/SiO 2 @TiO 2 enhanced by 42.4%, 196.9%, 10%, 24.4%, 66.7%, and 15.5%, respectively. The sample’s electrical, thermal, and color properties were also improved and showed the highest haze and lowest light transmissions. Such a simple and effective method of preparing “core–shell” structured SiO 2 @TiO 2 nanofillers provides great potential in industrial applications.