Moynihan model

Procedure

Dynamic measuring regime.

Sequential measuring regime.

Sequential measurements with w⁺ = │w^-│.

Several measurements at various heating rates, w⁺.

Then the activation energy ΔE^*_M (kinetic parameter) could be determined:

α = const (α – degree of conversion)

dln(│w│)d(1/T_α) = ΔE^*_M/R (w –heating or cooling rate)

ΔE^*_M = ΔE^*_DNLR (ΔE^*_DNLR - material parameter)

Model assumes:

First order kinetics.

An unknown spectrum of independent relaxation processes.

Three-parameter time-dependent relaxation times τ_j(T,t,T_a,t_a) = A_M,jexp (-B_MT)exp[-C_MH_excess(T,t,T_a,t_a)].

Complete separation of three forms of structural relaxation phenomena (irreversible relaxation exotherm, anneal-induced relaxation endotherms, glass transformation effect).

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