Effect of amino-modified SiO2 nanoparticles on micro-water diffusion behaviour in soybean oil-based natural ester oil-paper insulation system

Nanoparticles can significantly improve the insulation property of oil-paper insulation systems. In this paper, amino-modified SiO2 nanoparticles were used as nano-additives to establish a soybean oil-cellulose paper oilpaper insulation model, and the effect of amino-modified SiO2 nanoparticles on micro-water diffusion in oilpaper insulation systems was systematically studied. Simulation experiments show that amino-modified SiO2 nanoparticles can effectively delay the diffusion of water molecules in oil-paper insulation. As the temperature rises, compared with unmodified SiO2 nanoparticles, the diffusion motion of water molecules in amino-modified SiO2 nanoparticles oil-water model is slower. When the temperature is 383 K, the water molecule diffusion coefficient of the unmodified model is 1.22 times that of the modified model, and amino-modified SiO2 nanoparticles can form special hydrogen bonds with water molecules, preventing water molecules from further diffusing into cellulose paper, breaking the cellulose chain leads to a decrease in mechanical property, and further generating small molecules such as water and acid, which accelerate the aging of oil-paper insulation systems. Indirectly improve the electrical performance and aging performance of oil-paper insulation.