Monodispersed ZnO Nanoparticle-Poly(methyl methacrylate) Composites with Visible Transparency for Ultraviolet Shielding Applications

The inorganic–organic nanomaterials with high visible light transmittance have shown great potential in applications. However, it is difficult to disperse nanoparticles uniformly in organic matrices, resulting in an obvious decrease in transparency. This article reports a method to prepare ZnO-poly(methyl methacrylate) (ZnO-PMMA) nanocomposites with high transparency and excellent properties. First, a highly transparent nanodispersion of ZnO in methyl methacrylate (MMA) monomer is synthesized by the high-gravity reactive precipitation method. Then, ZnO-PMMA nanocomposites are prepared by the in situ bulk polymerization method. ZnO nanoparticles are about 6 nm with narrow size distribution, which monodisperse in MMA with the surface modifier containing C═C double bonds, contributing to the uniform dispersion of ZnO nanoparticles in PMMA matrices. Therefore, it ensures that the prepared ZnO-PMMA nanocomposites keep a high visible transmittance without any Rayleigh scatter. Moreover, ZnO-PMMA nanocomposites achieve multiple function applications of UV-shielding and anti-photo-aging, due to good thermal stability and high toughness and stiffness, which is attributed to the good dispersion of ZnO nanoparticles. After 200 h of UV radiation, pure PMMA obviously turns yellow and has a remarkable decrease in mechanical properties, whereas the nanocomposite is colorless and still keeps high visible transmittance and mechanical performances, which has great potential applications in the fields of optical materials and equipment.