International Confederation for Thermal Analysis ICTA

The Nomenclature Committee of the International Confederation for Thermal Analysis (ICTA) has defined DSC as a technique in which the difference in energy inputs into a substance and a reference material is measured as a function of temperature whilst the substance and reference material are subjected to a controlled temperature program. Two modes, power compensation DSC and heat flux DSC, can be distinguished depending on the method of measurement used1 . The relationship of these techniques to classical differential thermal analysis (DTA) is discussed by MacKenzie2). 

In contrast to calorimetric standards, there exists an official set of temperature standards for DTA and DSC measurements (Table 2). They were developed by the International Confederation for Thermal Analysis (ICTA). The materials can be obtained from this organization. These standards were created several years ago, when accurate T and AH measurements were still not possible to be made simultaneously. Unfortunately some of them are not suitable for calorimetric calibration, indicated by in... 

The 2nd International Conference on Thermal Analysis was held in Boston, USA, and at the same time the International Confederation for Thermal Analysis (ICTA) was established. ICTA has since been renamed the International Confederation for Thermal Analysis and Calorimetry (ICTAC)... 

In Fig. 4.8 the recommendations which have been given by the International Confederation for Thermal Analysis (ICTA) for the reporting of thermal analysis data are reproduced. It will be useful to read these recom-... 

HSBR HTNR HXSBR ICTA Hydrogenated styrene butadiene rubber Hydroxyterminated liquid NR Hydrogenated carboxylated styrene butadiene rubber International Confederation for Thermal Analysis... 

As with many other analytical techniques, the temperature axis used in differential thermal analysis (and DSC) must be calibrated with materials having known transition temperatures. The International Confederation of Thermal Analysis (ICTA) has been very active in developing a set of standard materials for this purpose (19) and has worked with the U.S. National Bureau of Standards to have these materials made commercially available (20). The U.S. National Bureau of Standards GM 754-GM 760 DTA temperature standards are listed in Table 6.2. They cover the temperature range from —83 to 925 C. The results of an ICTA round-robin study with 24 cooperating laboratories have been reported by Menis and Sterling (20). 

To establish a common basis for thermal analysis experiments, a series of ICTA (International Confederation for Thermal Analysis)-NBS (National Bureau of Standards) Standard Reference Materials were proposed via common experiments. These Standard Reference Materials have now been re-named ICTA Certified Reference Materials (CRM) and catalogued by the NBS (now NIST) as GM-758, GM-759 and GM-760 (see Table 1.4). The temperature standards of CRM are not the true transition temperatures of these materials, e.g. the difference between the extrapolated onset of a CRM and the equilibrium transition temperature is usually 3 "C. 

Major books dealing with thermogravimetiy are listed in the references at the end of the chapter. One important point is that ICTA, the International Confederation for Thermal Analysis, permits the abbreviation of thermogravimetry to TG, and has abandoned the earlier popular term thermogravimetric analysis and its abbreviation, TGA. The term thermogravimetry is, however, not abbreviated in this book, because of its easy confusion with Tg, the abbreviation for the glass transition temperature. 

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