▎ 摘　　要

NOVELTY - Conductive thermoplastic polyurethane (TPU) foamed bead with a surface coating comprises TPU foam beads, and an aqueous polyurethane solution containing carbon nanotubes and graphene spray-coated on the surface of the TPU foamed beads to form an aqueous polyurethane conductive coating having a thickness of 10-200 micrometer. The TPU foam beads are prepared by the gas impregnation method in the kettle, and the surface is cleaned and degreased by ultrasonic and activated by low temperature plasma. The aqueous polyurethane solution includes: an aqueous polyurethane, an aqueous slurry of carbon nanotubes, an aqueous graphene slurry, an aqueous antioxidant, a crosslinking agent, and deionized water. USE - Conductive TPU foamed bead with a surface coating used for preparing a molded body of a conductive TPU foamed bead (claimed). ADVANTAGE - The conductive TPU foamed bead with a surface coating have uniform conductivity and antistatic property, but also have stable static dissipative properties, and preparation process is environmentally friendly. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) a method for preparing a surface-coated conductive TPU foamed bead, which involves using spray coating and drying device, which drum-shaped drum with an open top, outlet of the hot air pipe that leads into the drum and is connected to a hot air blowing device outside the drum, stirrer installed in the drum to help disperse the TPU foam beads, and an atomizing spray gun with an outlet located in the drum and connected to a liquid tank outside the drum through a pipe; performing ultrasonic cleaning process to clean the surface of TPU foamed beads, and after cleaning, drying at 50-100 degrees C; using low-temperature plasma treatment process to treat the surface of the TPU foamed beads after cleaning; stirring aqueous polyurethane, carbon nanotube aqueous slurry, graphene aqueous slurry, water-based antioxidant, cross-linking agent, and deionized water uniformly, and using ultrasonic dispersion to prepare an aqueous polyurethane spray containing carbon nanotubes and graphene solution for use; adding the TPU foamed beads to the drum of the spray drying device, starting the drum to rotate and heating, and drying the material by hot air; pre-heating TPU foamed beads to a set drying temperature of 80-105 degrees C, and a stirrer is started to assist in dispersing the TPU foamed beads; spraying on the surface of the TPU foamed beads with a spray gun an aqueous polyurethane spray solution containing carbon nanotubes and graphene prepared, and during the process that the TPU foamed beads are uniformly rolled and dispersed in the drum; and spraying surface of the aqueous polyurethane spray solution containing carbon nanotubes and graphene on the surface for various times while being continuously heated and dried until the aqueous polyurethane solution is completely consumed, and the spraying is stopped, and forming a uniform coating on the surface of the TPU foamed beads, and drying is continued until the surface coating of the TPU foamed beads is dried; and (2) a method for preparing a molded body of a conductive TPU foamed bead with a surface coating, which involves adding conductive TPU foamed beads with a surface coating to the mold of a foamed bead molding machine, using steam heating treatment, cooling and demoulding.