Inorganic polymers, thermal analysis

As well as inorganic complexes, thermal analysis is applicable to a wide range of substances, e.g. polymers, drugs, soils and coals. It can also be applied to mixtures of, for example, polymer blends. 

The quadrupole mass spectrometer has been found to be particularly suitable for EGA in thermal analysis. Published reports include descriptions of the various systems used [153—155] and applications in studies of the pyrolysis of polymers [155], minerals [156] and many inorganic solids [157—159]. 

In our work, we have used thermal analysis and have confirmed that the transition temperatures of NIPA gels are very close to the cloud points of aqueous solutions of NIPA polymers [5]. This can be seen in Figs. 2 and 3 which compare the phase transitions in the presence of an inorganic salt and in the presence of a cosolvent such as DMSO [5, 6]. Clearly, the transition temperature of the gel shows the same tendency as that of the polymer. 

The lack of definitive studies is due to a mixture of reasons including 1) wide variety of polymers 2) newness of interest in the area 3) wide variety of applications (both potential and actual) of inorganic and organanetallic polymers not requiring thermal stability or thermal analysis (uses as anchored metal catalysis, control release agents, electrical and photochemical applications, speciality adhesives) 4) insufficient description, identification, of the products 5) wider variety of degradation routes and other thermal behavior in comparison to organic polymers and 6) many products were synthesized and briefly characterized before the advent of modern thermal instrumentation. 

Surveys of the types of thermal analysis techniques used and their applications to numerous areas cf research have been published by Wendlandt (6), Liptay (7), and Dunn (8). The most widely used techniques are TG and DTA, followed by DSC and TM A. Inorganic materials are the most widely studied by thermal analysis techniques, followed by high polymers, metals and... 

Utschick, H. Methods of Thermal Analysis Applications from Inorganic Chemistry, Organic Chemistry, Polymer Chemistry and Technology Ecomed Verlagsgesellschaft AG and Co KG Landsberg, Germany, 1999. 

Every two years, a fundamental review on thermal analysis is published in Analytical Chemistry, in which the development of new methods and the main applications to calibration, thermodynamics, kinetics, polymers, inorganics, pharmaceutical, biological, foods, etc. are reported [1-3]. Several articles regarding coordination compounds are cited and critically described. An update of the applications of evolved gas analysis (EGA), coupled to the thermoanalytical instruments, is also published every four years, and many studies on coordination compounds are cited [4-7]. 

In addition to the references discussed in the previous sections, there are a number of other references that provide examples of the use of thermal analysis and calorimetry in quality control and assurance situations. These are listed at the end of the list of other references. They cover polymers [46-71], organic chemicals [72-73], foods [74-76], inorganic chemicals [77] and metals [78-81]. Even this list of references is not nearly a complete bibliography of the use of these techniques in this area. 

The mercaptide thermolysis may behave differently in the presence or absence of polymers [Conte et al., 2007]. However, in most cases, the inorganic phase generated by the thermal degradation of mercaptide molecules dissolved in polymer corresponds exactly to that resulting from the thermal degradation of pure mercaptide. Consequently, a preliminary study of neat mercaptide thermolysis by thermal analysis approaches [differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA)] is usually performed before nanocomposite preparation and characterization. 

The step-growth polymerization of dibasic lithium phosphate is discussed next as an example of a polymerization reaction followed by immediate crystalhzation to the polymer, studied largely by thermal analysis [14,15]. It illustrates that not only organic molecules can be flexible macromolecules, but also inorganic ones. The two major techniques used for the analysis are differential scanning calorimetry (DSC, see Sect. 4.3) and thermogravimetry (TGA, see Sect. 4.6). The reaction equation is ... 

Sect. 4.6. Descriptions of thermogravimetry are given by Gallagher PG (1997) Chap 1 in Turi E, ed. Thermal Characterization of Polymeric Materials. Academic Press, San Diego Wunderlich B (1990) Thermal Analysis. Academic Press, Boston Duval C (1963) Inorganic Thermogravimetric Analysis, 2 ed. Elsevier, Amsterdam. (For decomposition of polymers see Refs to Sect 3.4). 

This handbook is designed to provide general information on the basic principles of TA and a variety of its applications. It is composed of two 1915 parts. Part I deals with information on the transition, reaction and characteristic parameters of substances. It introduces general principles, data 1919 treatment, experimental procedures and data analysis. Part II presents about 1000 typical 1945 thermal analysis curves, with brief explanations, for a wide variety of materials, such as polymers, 1960s foods, woods, minerals, explosives, inorganic compounds, and their coupled simultaneous 1964 curves. TA charts have been contributed by Institutes and Universities in China. Part III cites 1965 various data tables relating to thermal analysis. 

Thermal analysis has been used to study a wide range of phenomena occurring on a large number of materials, e.g., catalysts, polymers, liquid crystals, metals and alloys, organic materials, inorganic compounds, ceramics and glasses, etc. There is such a variety of applications for thermal analysis fliat it is not possible to include every aspect here. This section presents a representative range of applications of the three most widely used techniques (i.e., TG, DTA, and DSC) in fliermal analysis. 

Thermal Analysis vol. 1, Instrumentation, Organic Materials and Polymers vol. 2, Inorganic Materials and Physical Chemistry , ed. R. F. Schwenker and P. D. Garn, Academic Press, New York and London, 1969. 

Using this method one can characterize polymers, organic or inorganic chanicals, metals and other types of materials. The principal techniques of thermal analysis are differential scanning calorimetry (DSC) and thermo gravimetric analysis (TGA). 

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