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Sol-jel yöntemiyle gümüş-aşılanmış silikat esaslı antibakteriyel kaplamaların geliştirilmesi

Durucan, Caner
Dericioğlu, Arcan Fehmi
Akköprü, Betül
Ün, Nusret Serhat
There is a strong and urgent need for developing functional materials and surfaces that can prevent proliferation and survival of the bacteria to minimize the adverse effects of these microorganisms on public health. The objective of the project is establishing sol-gel based processing routes for development of silver biocide-doped antibacterial silicate based coatings and powders and determination material properties defining the antibacterial activity and durability. During the first phase of the project silver-doped silica based powders have been synthesized and the effects of modifications in sol-gel chemistry -acid catalysis and acid/base catalysis-and subsequent heat treatments on silica microstructure and on silver particles size have been investigated. The acid-catalyzed sol-gels formed a microporous silica network whereas the two-step catalyzed silica exhibited a mesoporous structure. It was found that mesoporous structure leads to formation of bigger silver particles and promotes crystallization of silica network upon calcination and improving the antibacterial performance. In the following phase, coating and heat treatment process parameters leading to formation of uniform and continuous silver-doped coatings on glass substrates have been defined. One critical finding related to coating properties was diffusion of the surface silver into the bulk upon calcination at temperatures higher than 500 °C. This compositional change causes degradation of antibacterial activity. In addition, the coating color change due to the chemical state of silver that can be present either in ionic (Ag+ ) or metallic state (Ag0 ) can be controlled by addition of aluminum into sol-gel formulation. In the final part of the project coatings on polyester-based fabrics have been developed for obtaining antibacterial/flame retardant dual functional textile finishes. The effects of textile surface pretreatment on coating erosion during laundering, on antibacterial activity and effects of different phosphorous components on flammability have been reported.