STUDY OF STRENGTH CHARACTERISTICS OF A COMPOSITE BASED ON POLYVINYL ALCOHOL, WOOD FLOUR AND THERMOPLASTIC STARCH

Currently, due to the deteriorating environmental conditions and a large number of difficult biodegradable under natural conditions materials, the great importance has the use of natural composite materials based on biodegradable polymers. In this context polyvinyl alcohol (PVA) as a polymer for the production of biodegradable composites which is not toxic and is able to decomposition in the natural environment is proposed. Due to the fact that the production of materials based on pure PVA is not economically feasible, it is proposed to add wood flour in the PVA that will allow you to obtain a marketable product from waste wood processing plants to reduce the cost. The composites made of PVA and wood flour, have relatively low hardness and flexural strength, therefore it is expedient the introduction of a third component of thermoplastic starch that is not a true thermoplastic but in the presence of plasticizer at high temperature is melted and liquefied, allowing you to use it for injection molding, extrusion and blow equipment. Thus this paper discusses the strength characteristics of biodegradable composite based on polyvinyl alcohol, wood flour of pine wood and thermoplastic starch depending on the quantitative content of the components. Studies have shown that the hardness of the samples with wood filler is higher than the hardness of pure samples on the basis of polyvinyl alcohol and that biodegradable hardness of the composite increases at higher amounts of wood filler. With increase of wood in the structure of composite water absorption also grows and accelerates the process of biodegradation. Thus, depending on the ratio of the components it is able to obtain the composite products with predetermined properties of biodegradation. The obtained biodegradable composite materials are environmentally friendly during production, consumption, recycling and can find application in the production of packaging products.