Estimation of the parameter of the main equation of the glass transition of amorphous polymers and other amorphous substances

Parameter C from the main glass-transition equation qτ_g = C according to Nemilov’s theory has the meaning of temperature bandwidth δT_g in which the freezing of the structure of the glass-forming liquid occurs (where q is the cooling rate of a melt and δ_g is the time of structural relaxation at the glass-transition temperature). The currently used method to estimate C results in inflated values, a circumstance that is due to the assumption of the constancy of the activation energy of the glass transition in the derivation of the calculation formula. Methods of estimation of C that are in agreement with the experimental data have been considered. A calculation of the time of structural relaxation, δ_g, on the basis of the values of the parameters of the Williams–Landel–Ferry equation has been proposed.