Preparation of SiO2/Si3N4ws/PU reinforced coating and its reinforcement mechanism for SLS‐molded TPU materials

Abstract

AbstractTo address the shortcomings of large porosity and insufficient mechanical properties of skeletonized Thermoplastic polyurethane (TPU) fabrications during the preparation of composite materials by selective laser sintering (SLS) technology. In this paper, SiO2@Si3N4ws‐GPTMS core‐shell structure filler was successfully prepared by first synthetically growing silicon dioxide (SiO2) nanospheres on the surface of silicon nitride whiskers (Si3N4ws) in situ by sol–gel method, and then modified with silane coupling agent Silane coupling agent (GPTMS). Then the filler was incorporated into the inner and outer surfaces of TPU skeletonized structural parts by vacuum dip coating using a water‐based polyurethane (PU) coating post‐treatment enhancement method, and the surface coating coating of TPU skeletonized structural parts was achieved by warming and curing. This composite filler coating structure greatly improved the mechanical properties of the SLS parts (tensile strength of 20.3 MPa and elongation at break of 338.9%, 163% higher tensile strength, 17.7% higher elongation at break, and 672% higher rebound dimension compared with the pure TPU sintered parts). In addition, the thermal stability of the SLS sintered parts was improved, which greatly enhanced the application of the sintered manufactured parts prepared by SLS technology in the field of rebound‐absorbing artificial wear.