Effect of accelerated aging on the color changes of wood treated with eco-friendly formulations based on propolis and silicon compounds

Abstract

The aim of this work was to determine the effect of propolis extract and propolis-silane formulations on the color of wood. Additionally, the aim was to assess the influence of accelerated aging (water leaching and UV+IR radiation) on the color change of the treated wood. Scots pine wood was treated with the ethanolic extract of propolis and two propolis-silane formulations. The first formulation contained the propolis extract and silanes, 3-(trimethoxysilyl)propyl methacrylate, and tetraethyl orthosilicate. The second formulation comprised propolis extract, vinyltrimethoxysilane, and tetraethyl orthosilicate. The wood impregnation with the propolis extract and propolis-silane formulations had a significant effect (p ≤ 0.05) on the color change. This effect involved decreasing the L* parameter and the displacement of a* and b* coordinates in the red and yellow direction, respectively. The propolis extract and the propolis-silane formulations were characterized by low durability relative to the effect of light. Nevertheless, the examined formulations based on natural substances (propolis) and low toxicity chemical compounds (silanes) may be used to impregnate wood elements for indoor applications.