The relaxation process of the sucrose in the glassy state and its glas
s transition are studied by differential scanning calorimetry in both
the conventional and the dynamic mode. The data on the kinetics of gla
ssy relaxation are experimentally evaluated by measuring the enthalpy
relaxation peaks as a function of the ageing times at three different
ageing temperatures, namely 45, 55 and 60 degrees C. It is shown that
the ageing process is a complex phenomenon with a rather large distrib
ution of relaxation times. The value of the breath of the distribution
of relaxation processes, beta, is 0.32 and it is in the lower range o
f the distributions commonly observed. The dynamic components of the h
eat capacity (C-p' and C-p '') have been obtained from the experiments
carried out at different frequency of temperature modulation (nu=8.3-
83 mHz). These components are unaffected by the ageing process and the
refore are more reliable for the correct T-g determination. The activa
tion energies for the relaxation process and for the glass transition
process are also evaluated. (C) 1997 Elsevier Science B.V.