New types of hyperbranched 1,2,3-triazole-alkoxysiloxane functional polymers for metal embedded nanocomposite surface coatings

In this study, using the "click-chemistry" azide-alkyne cycloaddition reaction, two new types of polymers, namely, water-soluble amine-functional and water-insoluble pyridine-functional hyperbranched 1,2,3-triazoleorganoethoxysiloxane polymers, capable of stabilizing ultra-small silver nanoparticles and efficient for chemical surface modification were synthesized and characterized by 1H-NMR, 13C-NMR, 29Si-NMR and FT-IR spectroscopy, MALDI and GPC. Coordinatively active hetero-organic polymers with a flexible branched polyethoxysiloxane backbone bearing chelating 1,2,3-triazolyl-dimethylamine and -pyridine conjugated functional groups were exploited towards coordination with Ag+ metal ions, and formation and stabilization of narrowly dispersed silver nanoparticles (Ag-NPs) obtained in the process of radiation induced metal ion reduction. The influence of the chemically assisted radiation process on the Ag-NP size and size distribution was investigated. Hyperbranched polyorganoethoxysiloxanes loaded with Ag-NPs were covalently cross-linked on a Stöber silica surface, demonstrating the efficiency of the developed hetero-organic functional polymers in the preparation of functional nanocomposite coatings for various applications (heterogeneous catalytic systems, antibacterial materials, nanoparticle-based optical sensing devices, etc.). The nanocomposites were investigated and characterized by TEM-EDS, DLS, UV-Vis spectroscopy and 29Si MAS NMR spectroscopy.