The development of glutin-based biocomposite materials with advanced hydrophobicity

Abstract

Biocomposite materials, which contain components of natural origin, have low resistance to water absorbtion due to high lyophilicity of components. It leads to quick destruction of biocomposite products under the conditions of high humidity exploitation that defines the necessity and importance of conducting scientific research in this sphere. The aim of the article is to research the hydrophobic additives influence on the compressive strength and hygroscopicity of biocomposite materials consisting of glutin matrix (100 parts by weight) and wood flour (100 parts by weight). The technology of forming biocomposite materials includes a step-by-step pressing the composition at a pressure of 10-15 MPa and a heat treatment of the product in a press mold at a temperature of 140°C. Experimental methods of investigating the biocomposite materials compressive strength and hygroscopicity were used in the work. It was experimentally determined that the modifying additive (paraffin) optimal content is 4 parts by weight per 100 parts by weight of biopolymer matrix. At this content, there is an increase compressive strength by 2.8-4.6 times of the biocomposite materials compared to biocomposites with different paraffin content. As a result of the state analysis of biocomposite samples which were destroyed under the static loading influence, the features of the cracks occurrence and propagation in biocomposites depending on different modifying additive content, the conduct of the composition preliminary processing or biocomposites additional processing in a thermal field were determined. The use of protective hydrophobic coatings on the biocomposite samples surface provided an increase in the biocomposites resistance to the moisture negative influence. The most effective were coatings based on a paraffin solution, which provided a reduction in water absorption by 45-50% compared to biocomposites coated with wax, drying oil Oksol, and sunflower oil. The complex use of hydrophobic substances as modifying additives and protective coatings has practical significance, as they positively affect the processes of forming the structure, increasing the strength and hydrophobicity of biocomposite materials used in a humid environment