▎ 摘　　要

NOVELTY - Preparation of graphene powder comprises taking graphite raw material, dispersant, and plugging layer, mixing, and adding into high pressure reaction kettle, where mass ratio of dispersant and graphite material is 0.01-20:1 and mass ratio of plugging agent and graphite material is 0-5:1; setting reaction kettle to 32-90 degrees C, pumping carbon dioxide, setting pressure to 7.4-30 MPa until carbon dioxide reaches supercritical fluid state, and circulation flowing for 10-300 minutes; repeating second step for 1-20 times; sonicating at 50-5000 W for 5 minutes to 5 hours; and spray drying at 50-300 degrees C. USE - Method for preparing graphene powder (claimed)used for polypropylene resin. ADVANTAGE - The method is simple, mild and easy to operate, does not destroy quality of graphite, increases product yield, produces high quality and yield graphene, uses low cost raw materials, and has no pollution. The graphene powder has excellent electric conduction, heat guide, and machine performance, greatly improves machinery strength of polypropylene resin, has antistatic performance, and increases added value of plastic.