Influence of humidity state on changes in the properties of polymer materials

The paper studies the influence of the moisture state on the elastic-strength parameters and kinetics of damage accumulation in the structure of epoxy polymer samples based on Etal-247 resin and Etal-45TZ2 hardener. Damage accumulation process is quantitatively described based on the author's technique determining the position of critical points on deformation curves of polymer materials using fractal analysis methods. has been established that an increase in the moisture content of a polymer material makes it possible to achieve, under tensile loads, formation of a pronounced stage of forced highly elastic deformations. We have revealed a decrease in the ultimate tensile strength and an increase in the relative elongation at break for moisture-saturated specimens compared to the polymer in the equilibrium-moisture state, by 5,3 and 5,4 times, respectively. It was found that at the ultimate moisture saturation, the rate of failure accumulation accelerates with an increase in the level of applied stress at strain compared to the samples in the equilibrium-moisture state, by 4,3-5,5 times.