▎ 摘　　要

NOVELTY - A thermoplastic polyurethane composite material comprises 90-100 pts. wt. polyurethane, 5-10 pts. wt. composite inorganic filler, 0-5 pts. wt. graphene, 0.1-1 pt. wt. light stabilizer, 5-10 pts. wt. coupling agent, 0.1-2 pts. wt. leveling agent, 1-6 pts. wt. dispersing lubricant and 0.1-1 pt. wt. antioxidant. The composite inorganic filler is made of composition containing graphene/silica composite filler and multiwalled carbon nanotubes/calcium carbonate composite filler. USE - Thermoplastic polyurethane composite material used in three-dimensional printing process. ADVANTAGE - The thermoplastic polyurethane composite material has excellent flexibility and mechanical property. DETAILED DESCRIPTION - A thermoplastic polyurethane composite material comprises 90-100 pts. wt. polyurethane, 5-10 pts. wt. composite inorganic filler, 0-5 pts. wt. graphene, 0.1-1 pt. wt. light stabilizer, 5-10 pts. wt. coupling agent, 0.1-2 pts. wt. leveling agent, 1-6 pts. wt. dispersing lubricant and 0.1-1 pt. wt. antioxidant. The composite inorganic filler is made of composition containing graphene/silica composite filler and multiwalled carbon nanotubes/calcium carbonate composite filler. Thermoplastic polyurethane composite is obtained by pulverizing polyurethane raw materials to the size of 300 mesh, dispersing in pure water, ultrasonically processing, carrying out microwave irradiation for 1 hour, washing, discharging, drying, obtaining pretreated polyurethane, ultrasonically stirring graphene/silica composite filler, dispersing in pure water, obtaining composite filler dispersion (I), ultrasonically dispersing multiwalled carbon nanotubes/calcium carbonate composite filler in pure water, obtaining composite filler dispersion (II), dissolving three-fifths of pretreated polyurethane in an organic solvent at heating temperature, obtaining polyurethane solution, dividing into three portions, mixing polyurethane solution (I) with composite filler dispersion (I), ultrasonically stirring for 30-60 minutes, dripping polyurethane solution (II), ultrasonically stirring for 30-60 minutes, continuously adding composite filler dispersion (II), ultrasonically stirring for 30-60 minutes, continuously dripping polyurethane solution (III), ultrasonically stirring for 30-60 minutes, obtaining filler polyurethane mixture, passing filler polyurethane mixture into reserve tank of spray dryer, spraying filler polyurethane mixture from spray dryer at the rate of 200-300 ml/minute, obtaining dried polyurethane/filler masterbatch, melt-mixing remaining pretreated polyurethane, polyurethane/filler masterbatch, graphene, light stabilizer, coupling agent, leveling agent, lubricant and antioxidant, adding to mechanical grinding mill, pulverizing and obtaining polyurethane composite powder having average particle diameter of 30-40 microns.