▎ 摘　　要

NOVELTY - Direct-current ultra-high voltage insulation composition comprises graphene nano sheet, and layered composite metal hydroxide, and the volume of the graphene nano sheet is 0.025-0.1 vol.% of the layered composite metal hydroxide. USE - The insulation composition is useful for preparing direct current ultra-high voltage transmission line insulation device (claimed). ADVANTAGE - The composite material: has excellent tracking resistance, electrical erosion properties and flame retardancy; and improves the mechanical properties of the material. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) preparing the direct-current ultra-high voltage insulation composition, comprising (i) adding the graphene nano sheet into the solvent, ultrasonically dispersing, then adding the prepared layered composite metal hydroxide and divalent or trivalent metal oxide, uniformly stirring, then placing in a ball mill for wet grinding, and drying, (ii) placing the resulting material in the ball mill, and dry grinding, and (iii) optionally adding the coupling agent dry grinding; and (2) direct-current ultra-high voltage insulation composite material, comprising the insulation composition and polymer basal body.