Preparation method of nano-SiO2 modified palm insulating oil

The invention provides a preparation method of nano-SiO2 modified palm insulating oil. According to the invention, when SiO2 nanoparticles are subjected to primary modification, -OH groups on the surface of SiO2 are removed through dodecyl trimethoxysilane and oleic acid, so a large amount of modified nano-SiO2 is compatible with palm insulating oil, and the phenomenon of agglomeration is reduced; the SiO2 nanoparticles having been subjected to primary modification are subjected to secondary modification through isobutanol, so -OH groups on the surface of SiO2 are further removed, and the heat-conducting property and insulation reliability of the insulating oil are greatly improved; tolyl diphenyl phosphate and alkylphenol polyoxyethylene ether are added into the secondarily modified SiO2 nanoparticles to prepare a SiO2 nanoparticle mixed solution, and then the SiO2 nanoparticle mixed solution is mixed with the filtered palm insulating oil, so the heat-conducting property and the insulating reliability of the