Thermal analysis nomenclature

In 1967, McAdie (1) reported the recommendations of the committee on standardization of the International Confederation of Thermal Analysis for reporting DTA or TG data. To accompany each DTA or TG curve, the following information should be reported  

Identification of all substances (sample, reference, diluent) by a definitive name, an empirical formula, or equivalent compositional data. 

A statement of the source of all substances, details of their histories, pretreatments, and chemical purities, so far as these are known. 

Measurement of the average rate of linear temperature change over the temperature range involving the phenomena of interest. 

Identification of the sample atmosphere by pressure, composition, and purity whether the atmosphere is static, self-generated, or dynamic through or over the sample. Where applicable, the ambient atmospheric pressure and humidity should be specified. If the pressure is other than atmospheric, full details of the method of control should be given. 

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The table below lists the various TA techniques following the notation of the ICTA (International Committee for Thermal Analysis) nomenclature committee. The three "classic" TA techniques are DSC, TGA and TMA of which DSC is still the "workhorse". TA is also covering, however, a substantial number of other techniques and applications and several of these techniques are described in this book. This book is not a comprehensive textbook about TA but more a survey of the author s work during many years, at the Koninklijke Shell Laboratorium in Amsterdam. It describes in six chapters the use of the various TA techniques (printed in bold in the table) for specific problems, illustrating the versatility of TA. A technical description is only given for equipment of own design. 

This thermal analysis nomenclature, which was progressively built up from the existing techniques, has needed to be updated to include more recent techniques... 

W. Hemminger, S. M. Sarge. Definitions, Nomenclature, Terms and Literature. In Handbook of Thermal Analysis and Calorimetry, vol. 1 Principles and Practice-, M. E. Brown, Ed. Elsevier New York, 1998 chapter 1. 

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). 

The International Confederation of Thermal Analysis (1CTA) nomenclature committee (17) defined EGD and EGA as ... 

In 1969, Mackenzie (2), Chairman of the ICTA Nomenclature Committee, published the first definitive nomenclature report. These recommendations should be adhered to in all English-language publications in thermal analysis. The recommendations are as follows. 

The nomenclature of thermal analysis continues to be a controversial and incompletely resolved topic. The system proposed by the ICTAC Nomenclature Committee chaired by W. Hemminger and described in detail by Hemminger and Sarge in Volume 1 [Vol 1, p 1-31] has since been reconsidered by a further Committee and die latest recommendations, which have been approved by the Council of ICTAC and by ASTM, are presented by Rouquerol et al. in Chapter 2 of this Volume. The current Committee has followed the advice of the late Robert Mackenzie in that ... 

By contrast, thermal analysis, which started to be recognized only one century later, developed a broadly accepted system of nomenclature more quickly. This was the result of collective work, conducted in the scope of the International Confederation of Thermal Analysis (ICTA), under the guidance of Robert Mackenzie from 1968 onwards. Once adopted by the Council of ICTA, this nomenclature was published in various papers [2-8] and also in booklets edited by ICTA [9-10]. Most importantly, it was endorsed by lUPAC [11-12] and, also, used as a reference by ASTM. 

The present official nomenclature for Thermal Analysis is thus contained in the Report of the ICTAC Nomenclature Committee, which is reproduced (with the permission of ICTAC) in Section 2. In Section 3 a number of extra comments are provided in order to justify, explain or complement the material in Section 2. 

This document acknowledges that nomenclature develops - without regulated definition - as the field of thermal analysis develops. Some terms used by authors and scientists rapidly become accepted by the scientific community, even if the term is not consistent with past definitions, science or grammatically correct. However, if such a term is widely used and understood, it is reported here. 

The nomenclature for thermal analysis and calorimetry is presently under review, so that recent developments and calorimetric methods may be included. The recommendations approved by the ICTA Council and by lUPAC are reported by Dr Robert C. Mackenzie in Treatise on Analytical Chemistry, Part 1, Vol. 12, Section J, ed. P. J. Hiving, Wiley, New York, 2nd edn., 1983. A provisional version was also given in For Better Thermal Analysis and Calorimetry, ed. J. O. Hill, ICTA, Edition III, 1991. However, this has not been approved by ICTA Council. A further revision is in preparation. 

Nomenclature in TA continues to be a controversial issue. The International Confederation of Thermal Analysis and Calorimetry (ICTAC) has essentially overseen developments in this domain over some four decades. However, practical nomenclature is determined by general acceptance, and a variety of factors affect this. The nomenclature recommendations released by Hemminger and Sarge in 2001, subsequent to widespread and intensive discussion with thermal analysts worldwide, have yet to be formally accepted by ICTAC. Likewise, modifications to the Recommendations for Reporting Thermal Analysis Data - as reported in the late 1960s and early 1970s - have yet to be approved by ICTAC. In short, developments on these issues have been severely curtailed by a lack of international agreement on the core principles. 

The definition given in the first report on nomenclature for thermal analysis (Part I) is as follows Thermal analysis A general term covering a group of related techniques whereby the depen-... 

Scheme 1.1 Changes and developments in the nomenclature for thermal analysis...

Thermal Analysis. A group of techniques in which a physical property of a substance is measured as a function of temperature, whilst the substance is subjected to a controlled temperature programme. The Nomenclature Committee of the International Committee on Thermal Analysis (ICTA) defines a wide range of techniques and their abbreviations, these being incorporated in ASTM E473-85. Those common in ceramics are (q.v.) differential thermal analysis (DTA) differential thermogravimetry (DTG) differential... 

The number of cases where adsorption microcalorimetry has been successfully applied to this end has increased in recent years, especially in the field of determination of the acidic function of molecular sieves, and extensive reviews of the systems investigated using this methodology have been published [2,5-18]. In particular, a review has been written [19] summarizing some of the most recently pubUshed results concerning the appUcations of microcalorimetry to the study of the acid/base sites of zeoUtes and meso-porous materials. The efficiency of thermal analysis techniques for the characterization of the acid/base strength of zeoUte materials is discussed, as weU as their ability to provide information consistent with catalytic data [19]. The reader is referred to the Atlas of Zeolite Structures [20] for nomenclature used throughout the text. 

Definitions, nomenclature, terms and sources of information in thermal analysis are to be found in refs. [15,16]. The basis of thermal analysis has recently been reviewed by Wunderlich [6], thermo-analytical instramentation, techniques and methodology by Gallagher [17] the history of thermal analysis was traced by Mackenzie [18]. Thermal analysis of polymers is described in various books [19-23] and reviews [24-28]. Thermal analysis is a powerful secondary technique. 

In the last decades several high-resolution techniques have been introduced. These techniques are event-controlled , i.e. when a thermal event (decomposition, evaporation, oxidation, etc.) occurs a change in measuring condition is introduced. Such event-controlled techniques are termed controlled rate thermal analysis (CRTA) [7] or reaction-controUed thermal analysis (RCTA) [195]. Nomenclature in the pertinent literature is confusing [7, 196]. Scheme 2.1 gives an overview of the relations between the methods which all aim at increasing the resolution of closely occurring thermal events. 

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