Development of eco-friendly antifungal coatings by curing natural seed oils on wood

Abstract

Protective green coatings are advantageous because they are eco-friendly and sustainable. In this study, three natural seed oils, tung, linseed and soybean, were used to investigate how coatings with different oil compositions could inhibit fungal growth. The oils were placed under direct sunlight to form cured films on maple wood. The curing chemistry and its effect on chemical resistance, water resistance and thermal stability were characterized and evaluated by FTIR, 13C NMR, solvent immersion, water contact angle and thermogravimetric analysis. The oil-coated samples were then placed on agar petri dishes that were spread with white-rot fungi. The areas of growth inhibition were measured over several days using an agar diffusion assay. The results showed that all oil-based coatings inhibited the fungal growth, with tung oil being the most effective followed by linseed and soybean oils. By mixing with a small fraction of tung oil, both linseed and soybean oils showed curing rates at least two times faster than individual oils and demonstrated much better inhibition of growth against fungi. This class of green natural seed oil coatings could be beneficial both economically and socially, given their high abundance, low cost, and environmental friendliness.