Surface-Functionalized ZnO Quantum Dot Fillers for Silicone Rubber Composites with Enhanced Antibacterial Performance

Graphical Silane coupling agent surface functionalized ZnO QDs(zinc oxide quantum dots) has been prepared with smaller size and lower tendency to agglomerate. ZnO-KH570 QDs has the best modification effect. When the dosage of ZnO-KH570 QDs is 0.1%, the inhibition rate of ZnO-KH570 QDs/RTV against Escherichia coli and Staphylococcus aureus can reach 99.9%. ZnO QDs (zinc oxide quantum dots) have potential value in the field of silicone rubber due to their excellent antimicrobial properties. However, the poor dispersion of ZnO QDs in silicone rubber limits their application. The surface functionalization of ZnO QDs can improve their dispersion in silicone rubber. This study showed that the surface of ZnO QDs could be effectively functionalized by using different kinds of silane coupling agents KH550 (3-aminopropyltriethoxysilane), KH570 (3-acryloyloxypropyltrimethoxysilane), KH580 (3-mercaptopropyltriethoxysilane), A151 (vinyltriethoxysilane) and HD128 (phenyltriethoxysilane). The surface-functionalized ZnO QDs show a reduction in particle size to 4–5 nm. The number and size of agglomerated particles on the surface of surface-functionalized ZnO QDs/RTV (room temperature vulcanized silicone rubber) composites were significantly reduced. Meanwhile, the surface roughness decreased by 92.10% (KH550), 93.08% (KH570), 91.36% (KH580), 85.43% (A151), and 90.86% (HD128), respectively, and the viscosity was increased by 2.90% (KH550), 4.35% (KH570), 2.90% (KH580), 1.54% (A151), and 3.62% (HD128), respectively. ZnO QDs-KH570 has the best dispersion effect. Furthermore, the antibacterial rate of ZnO QDs-KH570/RTV against Escherichia coli and Staphylococcus aureus achieved 99.9% when the additional amount of ZnO-KH570 QDs was 0.1%, which indicated excellent antibacterial performance and could contribute to the development of silicone rubber medical supplies.