Description of enthalpy relaxation dynamics in terms of TNM model

This article critically reviews the current methodologies for description of enthalpy relaxation dynamics in amorphous materials in the glass transition range. In particular, the description in terms of the Tool-Narayanaswamy-Moynihan (TNM) model is discussed. Advantages and disadvantages of particular methodologies are demonstrated and suggested explanations of possible data-distortive effects involve thermal gradients, improperly designed temperature programs, or incorrectly applied subtraction of the thermokinetic background. In addition, a novel ultimate simulation-comparative method is presented, applicable even for extremely distorted differential scanning calorimetry data. Based on the introduced advantages and disadvantages of particular methodologies, an optimum generalized algorithm for precise and reliable evaluation of TNM parameters is proposed, utilizing both curve-fitting and alternative non-fitting techniques.