Differential Scanning Calorimetry

Book excerpt: Differential Scanning Calorimetry (DSC) is a well established measuring method which is used on a large scale in different areas of research, development, and quality inspection and testing. Over a large temperature range, thermal effects can be quickly identified and the relevant temperature and the characteristic caloric values determined using substance quantities in the mg range. Measurement values obtained by DSC allow heat capacity, heat of transition, kinetic data, purity and glass transition to be determined. DSC curves serve to identify substances, to set up phase diagrams and to determine degrees of crystallinity. This book provides, for the first time, an overall description of the most impor tant applications of Differential Scanning Calorimetry. Prerequisites for reliable measurement results, optimum evaluation of the measurement curves and esti mation of the uncertainties of measurement are, however, the knowledge of the theoretical bases of DSC, a precise calibration of the calorimeter and the correct analysis of the measurement curve. The largest part of this book deals with these basic aspects: The theory of DSC is discussed for both heat flux and power compensated instruments; temperature calibration and caloric calibration are described on the basis of thermodynamic principles. Desmearing of the measurement curve in different ways is presented as a method for evaluating the curves of fast transitions.