A New Universal Photochemical Approach Towards the Formation of Durable Chemically Grafted Composite Coatings of Polymer Stabilized Ultra‐Small Narrowly Dispersed Silver Nanoparticles

ABSTRACT A novel, environmentally friendly photochemical approach for creating nanostructured surfaces adorned with narrowly dispersed ultra‐small silver nanoparticles (AgNPs) was developed using hybrid functional organoalkoxysiloxane hyperbranched polymers. The synthesized hyperbranched polymers embedded with AgNPs ( poly(en‐propylsiloxane) /AgNPs) were characterized with the methods of TEM, DLS, UV–Vis, and 1 H‐NMR spectroscopy. The sizes of roughly spherical, well‐distributed AgNPs were estimated as approximately 1–4 nm. The presence of a large number of residual alkoxy groups in the obtained reactive hyperbranched poly(en‐propylsiloxane) /AgNPs composites allowed for its covalent cross‐linking on the material surfaces and was used to chemically modify silica gel and cotton fabric materials while maintaining the sizes of the preformed AgNPs. Chemical interactions of the polymer matrix with the substrate surface, analyzed by solid‐state 29 Si‐NMR, confirmed for the covalent binding of poly(en‐propylsiloxane) /AgNPs with the material surface. SEM/EDX and TEM/EDX showed that chemically grafted nanocomposite coatings consist of uniformly distributed narrowly dispersed AgNPs (< D AgNPs ≥ 2.52 nm). Cotton bandages functionalized with uniformly distributed nanocomposite coatings demonstrated high efficacy against gram‐positive ( S. aureus ), gram‐negative ( K. pneumoniae ) bacteria and fungus ( C. albicans ) . Antibacterial properties of the obtained coatings were studied before and after repeated washings of the functionalized gauze bandages, and the composite coatings wash‐off resistance was estimated.