Papers by Keyword: Epoxy Polymers

Abstract: The paper proposes an approach to study the mechanism of deformation of epoxy polymers based on the methods of fractal calculations. The advantages of the method for determining the fractality index of the deformation curves of polymer samples using the minimum coverage method are shown. An algorithm for the quantitative determination of the location of the "critical" points of the deformation curves of polymer samples under tension is proposed. It is shown that the use of the developed methodology for the fractal analysis of time series on the basis of a set of points of deformation curves of epoxy polymer samples under tension, provides valuable information about the processes occurring in the structure of composite materials affected by mechanical loads and various aggressive factors.

Abstract: The change in the elastic-strength and sorption properties of epoxy polymers in the process of natural aging, taking into account the sequence of different climatic seasons effects, was studied. We studied polymers obtained on the basis of low-viscosity epoxy resins and a hardener, which is a mixture of aromatic and aliphatic di-and polyamines, modified by salicylic acid. Differences in the processes of structural relaxation and elimination of the initial nonequilibrium depending on the season of the exposure start are revealed. Mathematical models that describe changes in the elastic-strength properties of epoxy polymers during climatic aging, depending on the accumulated quantitative values ​​of the acting environmental factors, have been developed. For the first time, it was proposed to use as a variable parameter the total duration of time intervals for the studied period the surface temperature of the samples at which exceeded the glass transition temperature.