▎ 摘　　要

NOVELTY - Preparing graphene-modified nylon composite resin powder involves dissolving graphene oxide in a mixture of deionized water and ethanol, stirring for 1-3h, adding coupling agent dropwise under stirring for reaction at 70 to 100 degrees C for 8 to 24 hours, and the product is obtained by filtration and then washed with anhydrous ethanol and deionized water respectively for multiple times. The paste is placed in a drying oven at 60-110 degrees C for drying to obtain modified graphene oxide. The modified graphene oxide is mixed with lactam monomer and stirred for 1 to 3 hours at a temperature of 121 to 135 degrees C. USE - Method for preparing graphene-modified nylon composite resin powder used in three dimensional printing (claimed). ADVANTAGE - The method enables to prepare graphene-modified nylon composite resin powder, which has good mechanical properties, low shrinkage, good dimensional stability, low cost, good electrical and thermal conductivity, and is convenient for popularization and generalization. DETAILED DESCRIPTION - Preparing graphene-modified nylon composite resin powder involves dissolving graphene oxide in a mixture of deionized water and ethanol, stirring for 1-3h, adding coupling agent dropwise under stirring for reaction at 70 to 100 degrees C for 8 to 24 hours, and the product is obtained by filtration and then washed with anhydrous ethanol and deionized water respectively for multiple times. The paste is placed in a drying oven at 60-110 degrees C for drying to obtain modified graphene oxide. The modified graphene oxide is mixed with lactam monomer and stirred for 1 to 3 hours at a temperature of 121 to 135 degrees C. After the mixed monomer is placed in a reaction vessel, the temperature is raised to 120-140 degrees C and catalyst is added. After vacuuming for 10-30min, activators are added and stirred to polymerize at 170-185 degrees C, and then the graphene oxide modified nylon composite resin is obtained. The reactor is purged with high purity nitrogen, and heated to 230-260 degrees C to melt. The discharge port is opened, cooled, palletized to obtain graphene oxide modified nylon composite resin slices. The slices are placed in a high-pressure reactor, added with solvent and a reducing agent, sealed and heated to a temperature of 60-180 degrees C, stirred for 2-6h gradually, cooled to room temperature. The mixed solution is poured, filtered, washed, dried, graded to obtain a graphene modified nylon composite resin powder.