The dynamic crossover temperature and the characteristic length of glass transition in accordance with the extended Adam–Gibbs theory

Adam–Gibbs factor at the dynamic phase transition temperature is found out to be ‘universal,’ as it is at the glass transition temperature. A new scaling has been suggested collecting known ‘universalities’ related with the relaxation time. The fragility has been discussed in terms of the characteristic length at the glass-transition temperature. The transformation of the activation hopping into free diffusion dynamics in polymers is investigated.