UV-curable polyurethane acrylate–Ag/TiO2 nanocomposites with superior UV light antibacterial activity

Polyurethane acrylate (PUA)–Ag/TiO2 nanocomposites were synthesized through in situ polymerization. The well-dispersed Ag/TiO2 nanorods serve as photoinitiator. Meanwhile, the PUA–Ag/TiO2 nanocomposite films exhibit superior activity toward the photocatalytic degradation of Escherichia coli under UV light. The excellent UV curing and antibacterial activities can be ascribed to the synergistic effect of Ag and TiO2, which promotes the effective electron/hole separation and thus generates various reactive species. Thin films with these nanoparticles are more hydrophilic after UV illumination. And the antibacterial mechanism of the UV-curable PUA–Ag/TiO2 nanocomposites was proposed.

聚氨酯丙烯酸酯（Polyurethane acrylate, PUA）-Ag/TiO₂纳米复合材料通过原位聚合法合成。分散均匀的Ag/TiO₂纳米棒可作为光引发剂。与此同时，该PUA-Ag/TiO₂纳米复合薄膜在紫外光下对大肠杆菌的光催化降解表现出优异的活性。其优异的紫外固化性能与抗菌活性可归因于Ag与TiO₂的协同效应：该效应可促进电子与空穴的有效分离，进而产生多种活性反应物种。负载此类纳米颗粒的薄膜经紫外辐照后亲水性显著提升。本研究还提出了该紫外固化型PUA-Ag/TiO₂纳米复合材料的抗菌机制。