Fragility and equation parameters of glass transition

The relationship between a fragility (m), glass transition temperature (Tg) and tempera- ture strip (δTg) characterizing the transition temperature range of liquid- glass. δTg value is of a parameter of qτg = δTg glass transition equation (q - melt cooling rate, τg - re- laxation time at the glass transition temperature). It is shown that glasses of the same class, in which m = const, have linear correlation between δTg and Tg.