Rheological characteristics of modified wood

Abstract

The object of the study is birch wood, impregnated with polyester resin PN-1 and phenolic alcohols. Resin PN-1 is a filler, which do not penetrate the cell walls of wood, and phenolic alcohols, on the contrary, represent a class of fillers, which penetrate the cell walls. The degree of impregnation of wood is estimated by coefficient k. When impregnated with resin PN-1, it is equal to 0.8, when impregnated with phenolic alcohols – 0.2. To study the behavior of modified wood in long-term loading the real body is rep-resented as a set of two environments: perfectly elastic, deformable according to Hooke's law, and vis-cous, which obeys Newton's law. As with natural w ood in the description of creep modified birch wood we use rheological equation of Maxwell − Thomson, otherwise, the law of deformation “typical body”. The study of natural birch wood on base of what the modified wood is obtained is accomplished for the subsequent comparison of the rheological characteristics of these two materials. According to the experimental creep curves are defined instant and long elastic moduli, the relaxation time. Using these rheological characteristics, the coefficients of viscosity and modified natural birch wood are calculated. Rheological characteristics of modified wood appeared higher than those of natural wood.