Preparation of “needle-like” acid-activated sepiolite for enhancing fluororubber’s mechanical and heat resistance performance

Abstract

To improve the interfacial interaction between natural sepiolite (SEP) and fluororubber (FKM), an acid-activated sepiolite (GSEP) was prepared by modifying the natural SEP in inorganic acid solution. The GSEP appear fine needle-like nanostructures and has relatively higher specific surface area (181 %), maximum N₂ adsorption capacity (218 %), and purity compared to SEP. The silanol groups on GSEP formed Si-C bonds with FKM, which increased the cross-linking density of the composites, thus enhancing the mechanical and thermal conductivity of the FKM. Compared to FKM, the tensile strength, modulus at 100 % strain, hardness and initial decomposition temperature of the FKM/GSEP-15 were increased by 259 %, 150 %, 11.7 % and 14.5 °C, respectively. This work provides a new strategy for preparation of high performance FKM with high heat dissipation and high mechanical properties.