Several phenomenological models for describing the thermomechanical behavior of vitrifying materials are presented. The model is based on a unified approach using a scalar normalized parameter - the degree of vitrification, the hypotheses about the natural unstressed state and growing during the curing of the material of intermolecular bonds. The methods of experimental identification of the obtained constitutive relations and its implementation for two types of polymers (cross-linked and not cross-linked) are suggested. Comparison of calculation results and experiments to determine the technological and residual stresses in axisymmetric unevenly cooled samples is made. The approach proposed for polymeric materials is generalized for a class of low molecular vitrifying materials. The derived physical equations are used to solve the problem of preventing cracking of the parts where stress is applied to optical fibers and determining the optimal design parameters of the fiber.
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