▎ 摘　　要

NOVELTY - Polymer composite comprises polyolefin polymer matrix, and a graphene nanoplate; or graphite electrostatic attraction bond of hydrocarbons organic molecules on the sides. The graphene nanoplate includes hydrocarbon organic molecule bonded to the side surface. The hydrocarbon organic molecule is bonded to the hydroxy functional group or carboxy functional group on the side of the graphene nanoplate. The hydroxy functional group or carboxy functional group at the side of the graphene nanoplate is impurity of the graphene nanoplate. The hydroxy functional group or carboxy functional group at the side of the graphene nanoplate is a compound having hydroxy group at the side of the graphene nanoplate. The hydroxy functional group or carboxy functional group on side of the graphene nanoplate is present in reaction site at 10-15% of the entire surface of the graphene nanoplate. USE - The composite is useful in direct current power cables (claimed). ADVANTAGE - The composite has improved dispersibility. DETAILED DESCRIPTION - Polymer composite comprises polyolefin polymer matrix, and a graphene nanoplate; or graphite electrostatic attraction bond of hydrocarbons organic molecules on the sides. The graphene nanoplate includes hydrocarbon organic molecule bonded to the side surface. The hydrocarbon organic molecule is bonded to the hydroxy functional group or carboxy functional group on the side of the graphene nanoplate. The hydroxy functional group or carboxy functional group at the side of the graphene nanoplate is impurity of the graphene nanoplate. The hydroxy functional group or carboxy functional group at the side of the graphene nanoplate is a compound having hydroxy group at the side of the graphene nanoplate. The hydroxy functional group or carboxy functional group on side of the graphene nanoplate is present in reaction site at 10-15% of the entire surface of the graphene nanoplate. The hydrocarbon organic molecule is bonded to hydroxy functional group or carboxy functional group on graphite side. The hydroxy functional group or carboxy functional group on the graphite side is graphite impurity. The hydroxy functional group or carboxy functional group on the side of the graphite is produced by ozone treatment of side end of the graphite. The hydroxy functional group or carboxy functional group on the graphite side is present in reaction site at 10-15% of entire surface of the graphite. INDEPENDENT CLAIMS are also included for: (1) producing polymer composite, comprising (a) bonding the hydrocarbon organic molecules to side of the graphene nanoplate, and (b) mixing graphene nanoplate with the hydrocarbon organic molecules bonded with polyolefin polymer matrix; and (2) direct current power cable comprising a conductor, an inner semiconductive layer surrounding the conductor, an insulation layer surrounding the inner semiconductive layer and comprising the polymer composite, and an outer semiconductive layer surrounding the insulating layer.