▎ 摘　　要

NOVELTY - Exterior wall insulation material comprises closed-cell expanded perlite, fly ash, building gypsum, light calcium carbonate powder, bentonite, graphene-modified polypropylene, modified wheat shell, aluminum silicate fiber, polyether polyol, nano titanium dioxide, flame retardant, water repellent, and foaming agent; where the preparation of graphene-modified polypropylene comprises (1) premixing polypropylene powder, stabilizer, acrylic resin and graphene nano carbon material in high speed mixer to obtain mixed powder; where the weight ratio of the polypropylene powder, the stabilizer, the acrylic resin and the graphene nano carbon material is 100:8:2:1; and (2) melt-mixing the mixed powder obtained in the step (1) by torque rheometer at 160-180 degrees C under rotation speed of 40-80 revolutions/minute for 2-10 minutes to obtain graphene-modified polypropylene. USE - Used as exterior wall insulation material. ADVANTAGE - The material: has low thermal conductivity, high compressive strength, flexural strength, good aging resistance and excellent comprehensive performance. DETAILED DESCRIPTION - Exterior wall insulation material comprises 15-30 pts. wt. closed-cell expanded perlite, 20-40 pts. wt. fly ash, 15-25 pts. wt. building gypsum, 12-18 pts. wt. light calcium carbonate powder, 7-13 pts. wt. bentonite, 6-14 pts. wt. graphene-modified polypropylene, 7-14 pts. wt. modified wheat shell, 3-6 pts. wt. aluminum silicate fiber, 4-9 pts. wt. polyether polyol, 3-5 pts. wt. nano titanium dioxide, 1-4 pts. wt. flame retardant, 2-4 pts. wt. water repellent, and 2-3 pts. wt. foaming agent; where the preparation of graphene-modified polypropylene comprises (1) premixing polypropylene powder, stabilizer, acrylic resin and graphene nano carbon material in high speed mixer to obtain mixed powder; where the weight ratio of the polypropylene powder, the stabilizer, the acrylic resin and the graphene nano carbon material is 100:8:2:1; and (2) melt-mixing the mixed powder obtained in the step (1) by torque rheometer at 160-180 degrees C under rotation speed of 40-80 revolutions/minute for 2-10 minutes to obtain graphene-modified polypropylene. An INDEPENDENT CLAIM is also included for preparing the exterior wall insulation material comprising (1) taking closed-cell expanded perlite, fly ash, building gypsum, light calcium carbonate powder, bentonite, graphene-modified polypropylene, modified wheat shell, aluminum silicate fiber, polyether polyol, nano titanium dioxide, flame retardant, water repellent, and foaming agent; (2) mixing all the above materials in mixer, and stirring uniformly to obtain mixture, where the water content of the mixture is 30%; (3) adding water to the mixture obtained in the step (2), and continuing stirring with stirrer to obtain mixed slurry; and (4) placing mixed slurry obtained in the step (3) in mold, foaming and curing, drying in dryer.