the start of the capacitance jump observed by dsc upon the glass transition stage at a rate of 10 u00b0 c minute in this instance u03c4 tg is 3 10 u2212 3 s and the associated frequency f dsc such that 2 u03c0f u03c4 1 is about 50 hz in the case of the thermosetting resin in the presence of water measurement of the components of the complex dielectric permittivity is generally carried out under isothermal conditions at a known temperature t 1 if the swept frequencies range allows to determine u2208 0 and u2208 u221e a havriliak negami type parametered equation is adjusted to the curve in order to determine the characteristic time u03c4 1 of relaxation assuming that the apparent activation energy of the glass transition is of the same order in the plasticized material as in the non plasticized material the relaxation chart of the polymer material during use can be drawn see curve 2 in fig1 the relaxation chart of the polymer in the initial state and during use shown in fig1 being then available the tg of the plasticized material tgp is defined as the temperature associated with the characteristic time u03c4 tg on relaxation curve 2 of the material during use in this example the tg of the resin in the initial state is measured at 160 u00b0 c by dsc and the dielectric measurements allow to evaluate the plasticized tg at about 125 u00b0 c a value that is very close to the 120 u00b0 c calculated by means of the couchman karasz law knowing the amount of water absorbed under the gravimetric study conditions for information the tg of the plasticized resin measured by dsc at 10 u00b0 c min is clearly overestimated 135 u00b0.