Tri-functionally modified spherical silica for high-performance epoxy resin sealant

The integration of inorganic nanoparticles as reinforcement imparts epoxy resin with outstanding comprehensive performance, facilitating the utilization across diverse applications spanning coatings, adhesives, and composites. However, the persistent challenge lies in achieving optimal interfacial compatibility between the fillers and the resin matrix. This study focuses on the synthesis of tri-functionally modified spherical silica particles with an average size of 700 nm by empolying three distinct types of silane coupling agents in a synergistic manner to achieve desired functionalization. These agents endow the resulting particles with reactive groups, including epoxy and amine functionalities, which enhance interfacial compatibility and adhesion between the silica particle fillers and the epoxy resin matrix. Additionally, the incorporation of non-reactive phenyl groups serves to reduce the viscosity of resin composites. These modified silica particles are integrated into the sealant formulations, which exhibits commendable reliability and processability. It exhibits a 95 % reduction in moisture permeability, an increase in glass transition temperature by approximately 30 °C, and a decrease in coefficient of thermal expansion by 5∗10−6/k, compared to the sealant prepared with unmodified silica. The outcomes of this research present promising avenues for the advancement of cutting-edge display technologies. •Trifunctionally modified spherical silica was prepared by silane coupling agents.•700 nm spherical silica particles were incorporated into the sealant formulations.•The epoxy resin composites shows enhanced thermal and mechanical performance.•The application test of sealant in LCD panel exhibited commendable performance.