Glass transition relaxation and fragility in the molecular glass forming m-toluidine:: A study by thermally stimulated depolarization currents

The glass transition relaxation in m-toluidine was studied by thermally stimulated depolarization currents (TSDC). The departure from the zero entropy prediction, also called compensation behavior, was analyzed and the fragility index of the glass-former m-toluidine was calculated from the TSDC data according to a recently proposed procedure. The obtained result was compared with literature values. A particular attention was focused on the physical aging process of the nonequilibrium glass, which was followed easily because of its slow evolution. The influence of the aging temperature on the aging rate was analyzed. The significance of the so-called compensation point was discussed on the basis of the results obtained in this study of structural aging. (C) 2000 American Institute of Physics. [S0021-9606(00)50532-7].