اثر ترکیب رنگ، انواع نانو فلزی و سوبسترا بر بهبود مقاومت بیولوژیکی بر رنگ مصالح ساختمانی

This study aims to compare the biological resistance of paint materials which contain different resin types (i.e., acrylic v.s. polyvinyl acetate) and resin percentages (i.e., 20%, 30%, and 40%) before and after nano-metal treatment, as well as to explore the fungicidal effect of nano-metals (i.e. Ag, Cu and Zn) to improve fungal resistance of paints and the effect of the applied paint substrate (i.e. stainless steel, calcium silicate board and cement board) on the fungal growth. The Aspergillus brasiliensis or Penicillium funiculosum was inoculated on each sample and their growth was visually evaluated according to ASTM G21-09. The results show that Penicillium growth was a bit stronger than Aspergillus for each test under same conditions, and fungi could grow on paints whether they contain acrylic or polyvinyl acetate resins. Specifically, paints with 40% resin level were able to prevent fungal growth without treatment of nano-metals. The effect of nano-metals varied depending on substrate materials. For stainless steel, its effect was more visible on the speed of fungal colonization. On the final level of fungal contamination, the effect was only visible for Aspergillus on some combination of materials. For calcium silicate board and cement board, its effect was obvious on both speed and final level of fungal infestation. Nano-zinc seems to be the most favorable nano-metal for most test painted substrates in terms of reducing speed of fungal growth. Fungal growth on calcium silicate board and cement board with high porosity tends to slower than on stainless steel with low porosity.