Preparation of high-strength and heat-resistant fluororubber by incorporating dendritic mesoporous silica nanoparticles synthesized via an anion-assisted template method

This study synthesizes dendritic mesoporous silica nanoparticles (DMSN) via an anion-assisted templating method, utilizing sheet-like micelles formed from anion-cation complexes to direct silica condensation, followed by calcination. The obtained high-surface-area DMSN were incorporated as a filler into fluororubber (FKM) to fabricate FKM/DMSN composites. The extensive interface and mesoporous structure of DMSN provide sufficient areas for polymer chain adsorption, enhancing mechanical interlocking with the FKM matrix, significantly improving the composite’s properties. At an optimal loading of 10 phr, the composite demonstrates a tensile strength of 15.7 MPa, elongation at break of 300%, modulus at 100% strain of 3.8 MPa, and Shore A hardness of 68, representing increases of 292%, 36%, 217%, and 28%, respectively, over pure FKM. Additionally, the composite exhibits enhanced thermal stability with an initial decomposition temperature of 440 ℃, improved accelerated thermal transport, and retained electrical insulation alongside stable vulcanization characteristics. These superior mechanical and thermal properties make the DMSN-reinforced FKM composite a promising material for advanced sealing applications in aerospace, automotive, and energy sectors.