Differential thermal analysis (DTA) and differential scanning calorimetry (DSC) at high pressures. Experimental techniques and selected results

doi:10.1016/S0040-6031(94)85217-0

Thermochimica Acta

Volume 238, 15 June 1994, Pages 321-336

https://doi.org/10.1016/S0040-6031(94)85217-0 Get rights and content

Abstract

Three pieces of equipment are described that are used for thermal investigations at high pressures in our laboratories: a high-pressure differential scanning calorimeter (DSC) for experiments up to about 300 MPa, and two high-pressure differential thermal analysis set-ups (DTA) for measurements up to about 300 and 1000 MPa respectively. For each apparatus, characteristic results on one selected organic substance respectively (including plastic and liquid crystals) are presented and discussed, and references for additional applications are given.

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Other sources of error are the assumption of a constant heating/cooling rate for the sample, as this fails to take into account the effect of self-cooling or self-heating during reactions [29], and the assumption that the temperatures of the reference and sample are identical to those predicted by the heating/cooling program, as in real cycles there may be a considerable lag [30,31]. Several other factors are also known to have a profound effect on the shape of the thermoanalytical curves [19–21,23,25,27,32–39]. Although DSC and DTA provide similar data, researchers often choose to design and construct their own DSC apparatus because of the high cost of this type of equipment [40,41].
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Differential thermal analysis (DTA) and differential scanning calorimetry (DSC) at high pressures. Experimental techniques and selected results

Abstract

Thermochim. Acta

Physica

Thermochim. Acta

Thermochim. Acta

Thermochim. Acta

Thermochim. Acta

Thermochim. Acta

Thermochim. Acta

J. Chem. Thermodyn.

Physica

Thermochim. Acta

Pure Appl. Chem.

Z. Phys. Chemie (Leipzig)

Rev. Sci. Instrum.

Rev. Sci. Instrum.