Model ideas of thermal fracture on the basis of the theory of strenght

The theoretical ideas of polymer fiber lifetime are evolved. These ideas are based on the united model which combines three approaches such as kinetic, mechanical and thermodynamic. The ideological layout of the investigation of polymer destruction kinetic under thermal loading is described. The fundamental theoretical ratios for the polymer fiber lifetime are presented. The primary parameters and limit characteristics of the destruction process of polymer fiber under the stationary heat flow are calculated.