Description of temperature and time dependences of strength for oriented polymers over broad temperature intervals

Within the framework of the thermofluctuation concept of strength an equation has been derived which describes the dependence strength of oriented polymers on time and temperature. The equation takes into account the change in the statistics of atomic vibrations, which accompanies the crossing of the Debye characteristic temperature, and describes well the temperature dependence of strength of oriented, flexible-chain polymers as well as of polyimides between 80 and 800 K.