Differential scanning calorimetry enthalpy calibration

Differential scanning calorimetry (DSC) investigations were performed on a Perkin-Elmer DSC-2 apparatus equipped with scanning autozero. Polymer samples and inserts (8-10 mg) and equivalent amounts of pilocarpine salts (ca. 1.0 mg) were analyzed at heating-cooling rates of 20 /min under dry nitrogen flow. Indium standards were employed for temperature calibration and enthalpy change evaluation. 

Example Determination of the Heat of Fusion by Means of DSC Let us assume that the task is to determine the heat of fusion of an unknown sample by means of differential scanning calorimetry. The calorimeter is first calibrated by using a certified sample of indium of mass mdb = 10.12 mg as the calibration material. The certificate states an enthalpy of fusion of Afush<-ib = (28.64 0.06) Jg. Four measurements are performed and give the following results (peak areas 2 <-ii,) 284.15, 281.39, 263.49, and 276.04m). The mean value is Adb = 276.27 mj. The calibration factor Kq of the instrument is calculated according to the following equation ... 

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