PROTECTIVE TREATMENT OF WOOD with GLYOXAL
Wood has a unique combination of properties - low weight, high specific strength, good machinability, etc. All this has determined its wide application in various spheres of human activity. In addition, it has several disadvantages: low resistance to fire, high water and moisture absorption, low biological stability. This explains the urgent need to replace wood by material which is similar in properties, devoided its shortcomings and surpasses it in the quality. The current trend of production of new substitute materials of wood is connected with the creation of high-tech production of environmentally friendly material - thermoplastic wood-polymer composite (WPC). In appearance these materials are similar to wood and yet impervious to rot and mould, do not absorb moisture, do not have surface defects, high-tech and eco-friendly. In addition, the development of production technology of WPC allows not only to obtain innovative and competitive products, but also to solve the problems of processing wood and plastic waste. In this paper, wood polymer-sand composite (WPSC) with a matrix of polymer waste filled with wood waste is considered. To reduce the negative effects of moisture and microorganisms both on wood and composite as a whole is possible due to application of impregnating composition based on glyoxal. The paper discusses the influence of the temperature of impregnation on water absorption of wood specimens. The increase of temperature from 50 to 150 °C increases form stability of wood samples and decrease water absorption of test specimens. The results of the IR spectroscopy show that the interaction of the components of wood with glyoxal with the formation of ester bonds more actively proceeds at elevated temperatures. This relationship is valuable, given the fact that the products of WPSC are formed at temperatures above 200 <sup>о</sup>С.