▎ 摘　　要

NOVELTY - Preparing small sheet diameter graphene comprises mixing the graphite, water, glass microsphere, 1-pyrene methanol and methanol for sand grinding to obtain graphene/glass microsphere mixed suspension, where the glass bead includes a first glass bead, a second glass bead, a third glass bead and a fourth glass bead, the particle size of the first glass microspheres, the second glass microspheres, the third glass microspheres and the fourth glass microspheres is 400-600 μm, 150-300 μm, 50-100 μm and 1-40 μm, the mass ratio of the first glass microsphere, the second glass microsphere, the third glass microsphere and the fourth glass microsphere is 1-2:2-3:4-16:8-20, allowing to stand and settling graphene/glass microsphere mixed suspension to obtain the upper graphene of the suspension, spraying and drying graphene suspending solution. USE - The method is useful in polyethylene terephthalate composite material (claimed). ADVANTAGE - The method improves the mechanical property and conductivity of polyethylene terephthalate material. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: the small sheet diameter graphene prepared by above method; a polyethylene terephthalate composite material comprising 5-45 pts. wt. graphene, 50-90 pts. wt. polyethylene terephthalate, 0.003-0.01 pts. wt. chain extension and 0.003-0.01 pts. wt. antioxidant , where graphene is the small sheet diameter graphene; and a method for preparing polyethylene terephthalate composite material comprising mixing graphene, polyethylene terephthalate, chain extender and antioxidant for double-screw extruding .