International Confederation of Thermal

Ferguson. J. M P. M. Livesey, and D. Mortimer. International Confederation of Thermal Analysis 111, Davos, Switzerland. Aug. 1971. Paper 1. 

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). 

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

According to the International Confederation of Thermal Analysis (ICTA), the thermal analysis technique of thermoelectromerrv is denned as a technique in which the electrical characteristics of a substance is measured as a function of temperature whilst the substance is subjected to a controlled temperature programme. (49) The most common measurements, according to ICTA. are of resistance, R, conductance. A, and capacitance. C. However, since A = liR I — E/R, and E is usually constant. A = / = k,R thus, many investigations report the use of current. /. plotted as a function of temperature. Indeed. David (97) used the term amperomecric thermal analysis (ATA) to describe the technique that he developed. 

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 ... 

According to the definition presented by the International Confederation of Thermal Analysis and Calorimetry (ICTAC), thermal analysis is a group of techniques in which a physical property of a substance is measured while the substance is subjected to a controlled temperature programme . Table 7.3 summarizes the most important techniques that are briefly discussed below. 

Lombardi, G. (1980) For better Thermal Analysis, 2nd edn, published by the International Confederation of Thermal Analysis and Calorimetry (ICTAC). 

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. 

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. 

International Confederation of Thermal Analysis and Calorimetry infrared... 

The viscosity of a material suddenly changes and loses fluidity at the gel point. Techniques to follow this phenomenon as a function of temperature are called thermal analysis techniques. According to the definition of the International Confederation of Thermal Analysis and Calorimetry, thermal analysis is a series of collective techniques to measure the physical properties of a material (or a reaction product) by changing the temperature according to a certain program [212, 213]. There are various thermal analyses depending on the physical properties to be measured. In this section, differential scanning calorimetry (DSC), which is the technique to measure heat capacity of the sample, and thermomechanical analysis (TMA), which measures the viscosity or modulus, will be discussed. 

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). 

Thermal analysis systems require calibration prior to routine use. In TGA, calibration for mass is carried out by calibrating the microbalance using a set of standard weights, as for any balance system. Temperature calibration is effected by measuring the Curie point temperatures of a suite of International Confederation for Thermal Analysis and Calorimetry (ICTAC) Certified Reference Materials, which have well-defined Curie points. ... 

Detailed suggested guidelines for reporting results can be found in For Better Thermal Analysis produced by the International Confederation for Thermal Analysis and Calorimetry (7). A summary of the key parameters for DSC experiments is given here for convenience ... 

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 scheme of the elements of the ancient Greek philosophers of some 2500 years ago contained heat (fire) as one of the four basic elements. The other three elements were the phases, gas (air), liquid (water), and solid (earth) as discussed in Sect. 2.5 and Chap. 5. Figure 2.1 is an illustration of this ancient scheme. It is interesting that the logo of the International Confederation for Thermal Analysis and Calorimetry,... 

The term thermal analysis can be applied to any technique which involves the measurement of a physical quantity while the temperature is changed or maintained in a controlled and measured fashion as expressed in Fig. 2.4. Usually the temperature is, for simplicity, kept constant or increased linearly with time. Recently, it was found advantageous to superimpose a small modulation of the temperature to check for the reversibility of the measurement and to separate the calorimeter response from inadvertent gains or losses that do not occur with this modulation frequency (see Sect. 4.4). The professional organizations of thermal analysis are the International Confederation for Thermal Analysis and Calorimetry, ICTAC, and the North American Thermal Analysis Society, NAT AS, described in some detail in Figs. 2.5 and 2.6, respectively. The most common journals dealing with thermal analysis techniques and results are ThermochimicaActa and the Journal of Thermal Analysis and Calorimetry. 

All basic techniques of thermal analysis treated in this chapter are already mentioned in Sect. 2.1.3, together with a number of further, less basic techniques. The thermal analysis tools are grouped according to the variables they are designed to determine, as is summarized in Fig. 2.4. The International Confederation for Thermal Analysis and Calorimetry, ICT AC, and the regional North American Thermal Analysis Society, NATAS, are the scientific organizations concerned with this field of science (see Figs. 

Reference material sets which are certified by the International Confederation for Thermal Analysis and Calorimetry (ICTAC) are available through the US National Institute of Standards and Testing (NIST), and are listed in Appendix 2.2. High-purity metals and organic compounds including polymers have been certified. If the standard reference material must be dispensed with a syringe into the sample vessel (for example cyclohexane), care must be taken to ensure that only one droplet is formed in the sample vessel. Multiple transition peaks will be observed if there is more than one droplet present. The transition temperatures listed in Appendix 2.2 are the statistical mean values of measurements made in a number of laboratories and institutes. The ICTAC reference materials are certified for temperature calibration only and not for enthalpy calibration. The reference temperatures in Appendix 2.1 should be used if very accurate calibration of the instrument is required. In order to determine the heat capacity Cp ) of a sample, sapphire (a-alumina, AI2 O3) is used as a standard reference material. The Cp of... 

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. 

Two journals (the Journal of Thermal Analysis and Calorimetiy and Thermochimica Ada) devote their contents entirely to TA the Proceedings of the (now) four-yearly Conferences of the International Confederation for Thermal Analysis and Calorimetry (ICTAC) constitute an excellent additional. source of research papers. Specific information regarding Proceedings volumes for the nine ICTAC Conferences between 1965 and 1991 is available in [1]. The most complete listing of worldwide TA literature is also found in the ICTAC handbook [1], which in addition gives addresses for national TA societies and important equipment suppliers. The most useful textbooks include [2]-[5]. 

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