▎ 摘　　要

NOVELTY - The method involves mixing dispersant and powder waterproof agent diluted liquid uniformly to obtain the dispersion, where powder comprises gas phase silicon dioxide powder, crystalline flake graphite powder, expanded graphite powder and graphene powder. The expansion perlite dispersion liquid is put. Stirring is performed uniformly. Vacuum impregnation is performed. Drying is performed to obtain the pre-modified expansion perlite after finishing dipping. Waterproof coating is performed on the pre-modified expanded perlite. Drying is performed to obtain the modified expanded perlite. USE - Method for preparing a modified expansion perlite for thermal insulation material (claimed). ADVANTAGE - The method enables performing waterproof modification on the expansion perlite under the premise of not increasing or even reducing the heat conductivity coefficient, thus achieving excellent heat preservation performance. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of a microcosmic appearance pattern.