▎ 摘　　要

NOVELTY - Preparing multilayer graphene comprises (i) preparing mixed solution containing graphite, intercalation agent and a surfactant to obtain intercalated modified graphite; (ii) mixing intercalated modified graphite with water-soluble thermoplastic polymer in a twin-screw extruder, injecting into single-screw extruder and injecting a supercritical fluid into single-screw extruder to obtain a foamed expanded material; and (iii) ultrasonically foaming expansion material. USE - The method is useful for preparing multilayer graphene. ADVANTAGE - The multilayer graphene: has high uniformity of film diameter and layer thickness.