▎ 摘　　要

NOVELTY - Graphene-modified vegetable insulating oil comprises refined vegetable oils, graphene and composite antioxidant, where the mass concentration of the graphene in the vegetable oil is 80-100 mg/l, and the mass concentration of the composite antioxidant in the vegetable oil is 5-30 mg/l. The vegetable oil is rapeseed oil which is subjected to alkali refining, decolorization and vacuum distillation treatment, and has a flash point of higher than 350 degrees C. USE - As graphene-modified vegetable insulating oil. ADVANTAGE - The insulating oil has excellent oxidation stability, high flame retardance and excellent fire resistance. The insulating oil has excellent insulation, thermal conductivity, excellent usage performance, prolonged service life and high safety factor, and meets the need of large-capacity, ultra-high-voltage insulation cooling media. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing the insulating oil, involving (i) adding graphene to the refined vegetable oil which is subjected to drying, and ultrasonically dispersing to obtain a graphene-modified vegetable oil, (ii) dissolving tert-butylhydroquinone, 3,4,5-trihydroxybenzoic acid, vitamin E and tocopherol in a reserve vegetable oil, and uniformly mixing and stirring to obtain the composite antioxidant, and (iii) adding the composite antioxidant to the graphene-modified vegetable oil, and uniformly stirring to obtain the graphene-modified vegetable insulating oil.