▎ 摘　　要

NOVELTY - Preparing graphene nylon composite powder material comprises (1) adding nano-graphene oxide, nylon salt and molecular weight regulator in the mass ratio of: 10-25%, 74-89.5%, 0.5-1% into the polymerization kettle, and adding deionized water to carry out the polymerization reaction, water cooling, then discharging the strip and pelletizing to obtain low molecular weight graphene nylon pellets; (2) mixing the low-molecular-weight graphene nylon pellets and high-molecular-weight nylon pellets according to a mass ratio of 1:5, and then adding to the powder making kettle, and then adding a solvent, after powdering and drying sieving through the solvent method to obtain the graphene nylon powder; and (3) mixing the graphene nylon powder, nano-graphene oxide, flow additive and antioxidant according to the following mass fraction ratios: 95-99.5%, 0.1-0.5%, 0.1-2% and 0.2-2%; and screening to prepare graphene nylon composite powder material for selective laser sintering. USE - The composite powder material is useful for selective laser sintering. ADVANTAGE - The composite powder material: has greatly improved mechanical properties, good reusability and good heat absorption performance. DETAILED DESCRIPTION - Preparing graphene nylon composite powder material comprises (1) adding nano-graphene oxide, nylon salt and molecular weight regulator in the mass ratio of: 10-25%, 74-89.5%, 0.5-1% into the polymerization kettle, and adding deionized water to carry out the polymerization reaction, water cooling, then discharging the strip and pelletizing to obtain low molecular weight graphene nylon pellets; (2) mixing the low-molecular-weight graphene nylon pellets and high-molecular-weight nylon pellets according to a mass ratio of 1:5, and then adding to the powder making kettle, and then adding a solvent, after powdering and drying sieving through the solvent method to obtain the graphene nylon powder; and (3) mixing the graphene nylon powder, nano-graphene oxide, flow additive and antioxidant according to the following mass fraction ratios: 95-99.5%, 0.1-0.5%, 0.1-2% and 0.2-2%; and screening to prepare graphene nylon composite powder material for selective laser sintering; where the relative molecular mass of the low molecular weight graphene nylon pellets is 1-3 million, and the relative molecular mass of the high molecular weight nylon pellets molecular mass is 100,000-300,000.