In Situ Polymerization on Photocatalytic Nanoparticles and Composites

The combination of nanoparticles (NPs) and polymers has shown promise in creating advanced organic-inorganic hybrid materials that surpass the capabilities of individual organic or inorganic components. However, achieving controlled self-assembly of these two distinct components in such hybrid materials remains challenging due to intricate forces at the organic-inorganic interface, hindering the direct assembly of supramolecular or polymer structures on NP surfaces and often resulting in phase separation of the two entities. Here, we present novel methods for polymerizing various methacrylate monomers directly on the surface of tungsten oxide hydrate (WO_3-x●H₂O) NP photocatalysts, promoting ordered NP distribution in the polymer matrix through self-assembly of stereoregular polymers with NPs. WO_3-x●H₂O nanoparticles, featuring free radicals on their transition metal oxide surface and an average core size of approximately 1.6 nm, initiate the stereoregular polymerization of methacrylate monomers under UV-light irradiation. The NPs can be incorporated into the polymer matrix during reactions, and the resulting NP-initiated composites exhibit stable optical and enhanced mechanical properties with stereoselective characteristics and crystallinity based on the surface ligands used for NP synthesis. This makes them suitable for applications requiring unique optical and strong mechanical properties. Our findings are expected to pave the way for high-performance hybrid composite materials that feature precisely controlled assembly, providing customized properties crucial for applications demanding superior optical clarity, mechanical strength, and environmental stability.