Modulated (temperature) differential scanning calorimetry (MTDSC or MDSC) i
s used to study simultaneously the evolution of heat flow and heat capacity
for the isothermal and non-isothermal reactions of polymer systems. An epo
xy-anhydride thermosetting system is treated as an example. Vitrification a
nd devitrtification steps are observed.
The heat flow phase during isothermal and non-isothermal cure is always sma
ll, but its evolution contains information on relaxation phenomena, vitrifi
cation and devitrification, in the course of the chemical reaction.
Modelling of the (heat flow related) chemical kinetics and the (heat capaci
ty related) mobility restrictions contributes to a better understanding of
the reaction mechanism and reaction kinetics up to a high degree of chemica
l conversion. The use of MTDSC as a tool for a quantitative construction of
the vitrification curve in Temperature-Time-Transformation (TTT) and Conti
nuous-Heating-Transformation (CHT) diagrams is illustrated.