Preacetylation of wood filler in composite materials production

The increasing swelling pressure of wood filler, occurring during the use of a composite material, leads to the formation of internal microcracks, therefore, reducing the hygroscopicity of the wood filler is an urgent task. This paper considers the wood filler preacetylation technology in wood-polymer composite materials production. Wood particles were acetylated by soaking them in acetic anhydride, followed by heating in a vacuum drying cabinet at 120°C for 40, 180, and 360 minutes. Polylactide in various binder-modified wood filler ratios was used as a polymer matrix in wood-polymer composite samples. The resulting samples were examined for moisture and water absorption. It was found that with a maximum treatment time of 360 minutes moisture and water absorption of samples with 40% wood filler content did not exceed those of a composite with 20% unmodified wood filler content, which proves the effectiveness of acetylation. The results of the research conducted allow expanding the scope of use of additive manufacturing products.