ZnO Nanoparticles Coated with Amphiphilic Polyurethane for Transparent Polyurethane Nanocomposites with Enhanced Mechanical and UV-Shielding Performance

To optimize the dispersion and interfacial interaction of ZnO nanoparticles in UV-curing poly(urethane acrylate) (PUA) nanocomposites, a series of amphiphilic polyurethane (APU)-functionalized ZnO nanoparticles were prepared by an inverse miniemulsion process at room temperature. The ZnO nanoparticles functionalized with poly(tetramethylene glycol) (PTMG) based APU end-capped by various hydroxyl-containing compounds, including butyl alcohol (BA), hydroxyethyl methacrylate (HEMA) and pentaerythritol triacrylate (PETA), could be well dispersed in toluene and acrylic monomers (methyl methacrylate, HEMA). Compared with PTMG-APU-BA-ZnO and PTMG-APU-PETA-ZnO, the incorporation of PTMG-APU-HEMA-ZnO nanoparticles (0.3 wt %) into PUA significantly enhanced the Young’s modulus, tensile strength, toughness, and UV-shielding properties without compromising the high transparency of PUA nanocomposites. This study provides a new strategy for designing high-performance ZnO nanocomposites with potential to be used in advanced nanocomposite coatings.