Surface-Coated Silicone-Modified Waterborne Polyurethane With Implanted Superhydrophobic SiO2 Nanoparticles Preparation and Study of TPU Self-Cleaning Material

Abstract

This study presents the synthesis of a waterborne polyurethane (WPU-A) emulsion modified with (3-(2-aminoethyl)aminopropyl)trimethoxysilane (AEAPTMS). Self-cleaning materials were developed by applying WPU-A emulsions onto thermoplastic polyurethane (TPU) components, which were shaped using selective laser sintering (SLS), through a post-treatment impregnation and curing method. Additionally, superhydrophobic nano-SiO₂ (sn-SiO₂) was incorporated onto the surface of the TPU/WPU-A material. The resulting TPU/WPU-A/sn-SiO₂ self-cleaning composites were created, and the self-cleaning capabilities along with other characteristics of the two TPU-coated materials were examined individually. Findings indicated that the water contact angle for pure TPU measured 123.8°, while the TPU/WPU-A0.5/sn-SiO₂-20, treated with WPU-A emulsion, exhibited an increased angle of 153.3°, achieving superhydrophobicity. The incorporation of sn-SiO₂ particles enhanced the surface roughness of the TPU/WPU-A0.5/sn-SiO₂-20 material, facilitating the easy removal of surface contaminants. This enhancement contributes to improved anti-pollution properties and effective self-cleaning performance of the TPU material. The compressive strength of the TPU/WPU-A0.5/sn-SiO₂-20 skeletonized parts reached 0.733 MPa, representing a 168% increase compared to the pure TPU skeleton. The TPU/WPU-A0.5/sn-SiO₂-20 material, which is coated with WPU-A and integrated with sn-SiO₂, demonstrates excellent self-cleaning and mechanical properties, indicating its potential for various applications.