PREPARATION AND RESEARCH OF WOOD-POLYMER COMPOSITES WITH SIMULTANEOUS MODIFICATION OF THE POLYMER MATRIX AND WOOD FILLER

Abstract

In this article, new WPC compositions were developed and their technological and operational properties were investigated, with special attention paid to WPC with high water resistance and fungus resistance. The use of waste that is difficult to recycle, such as expanded polystyrene and thermoplastic polyurethane, for the modification of the wood filler and polymer matrix was proposed. This solution additionally contributes to solving the environmental problem and improves the operational and physicochemical properties of WPC products. To determine the moisture content both in the finished product and at the intermediate stage of production, methods for determining the dielectric permittivity, dielectric loss tangent and electrical resistance were used. The determination of these indicators made it possible to timely determine the presence of moisture in the polymer matrix and wood filler in order to adjust the WPC production process. The method of simultaneous modification of both the polymer matrix and the wood filler was used, which gives a synergistic effect and is promising and effective for preventing water absorption, for improving the physical and mechanical properties and extending the service life of WPC products. The effectiveness of the method of simultaneous modification of WPC with a synergistic effect is confirmed by tests only at the level of dielectric characteristics of the obtained samples, which is evident from the results of the study. From the results of studies of the influence of WPC modification on the level of resistance to external conditions and the level of the dielectric loss tangent tg, it is proven that effective binding of free water in WPC allows to increase the complex of dielectric characteristics. The process of modification of the polymer matrix and wood filler was analyzed using infrared spectroscopy. This made it possible to conclude that the most significant effect of filler modification is associated with a decrease in the number of free hydroxyl groups after impregnation with the modifying mixture.