Thermogravimetric Study

From infrared and thermogravimetric studies, Pechkovskii et al. [836] identify the following steps in the decomposition of Mg(H2P04)2 2 H20. 

Marinho EP, Souza AG, de Melo DS, Santos IMG, Melo DMA, and da Silva WJ. Lanthanum chromites partially substituted by calcium strontium and barium synthesized by urea combustion—Thermogravimetric study. J. Thermal Analysis Calorimetry 2007 87 801-804. 

Thermogravimetric studies of polymer stability in these perfluorinated systems show an onset of degradation at 407°C, which is nearly 100°C lower than with other comparable polyimides. ... 

Thermogravimetric studies were done with derivatograph (17). Thermal curves were recorded at 10°/min. The standard was A1203 heat treated at 1600°C. 

A good-quality CeMCM-41 material with Si/Ce=50 was synthesized by hydrothermal method. For the purpose of comparison a pure siliceous MCM-41 was prepared using the same composition without cerium. Thermogravimetric curves for the synthesized uncalcined samples exhibit shape characteristic for the MCM-41-type materials. The specific surface area of CeMCM-41 evaluated from nitrogen adsorption was equal to 850 m2/g, whereas the pore width and mesopore volume of this material were equal to 3.8 nm and 0.8 cm3/g, respectively. In contrast to the pure silica MCM-41, the CeMCM-41 material exhibits medium and strong acid sites as revealed by thermogravimetric studies of n-butylamine thermodesorption. 

Modification of the mesoporous silica with alkylchlorosilanes resulted in the increase of the weight loss on the TGA curves (Fig. 5). Thermogravimetric studies revealed a great similarity of the samples modified via conventional and one-step procedures. As can be seen from Fig. 5 the sample with attached longer alkylsilane prepared via one-step procedure has much higher surface coverage than that obtained via conventional modification. A notable difference in the shape of the DTG curves for the MCM-UO and MCM-CO samples could be attributed to the presence of the different conformations of the attached alkyl groups [12]. 

Boussehain, R., Feidt, M. L., and Balesdent, D. (1986). Thermogravimetric study of alcohol adsorption on active charcoal. Thermochim. Acta 103(1), 113-122. 

Schnitzer, M., Turner, R. C., and Hoffman, I. (1964). A thermogravimetric study of organic matter of representative Canadian podzol soils. Can. J. Soil Sci. 44,7-13. 

Incorporation of modified clays into thermosetting resins, and particularly in epoxy35 or unsaturated polyester resins, in order to improve thermal stability or flame retardancy, has been reported.36 A thermogravimetric study of polyester-clay nanocomposites has shown that addition of nanoclays lowers the decomposition temperature and thermal stability of a standard resin up to 600°C. But, above this temperature, the trend is reversed in a region where a charring residue is formed. Char formation seems not as important as compared with other polymer-clay nanocomposite structures. Nazare et al.37 have studied the combination of APP and ammonium-modified MMT (Cloisite 10A, 15A, 25A, and 30B). The diluent used for polyester resin was methyl methacrylate (MMA). The... 

Santra RN et al. (1993) Thermogravimetric studies on miscible blends of ethylene-methyl acrylate copolymer (EMA) and polydimethylsiloxane rubber (PDMS). Ther-mochim Acta 219(1—2) 283—292... 

Based on thermogravimetric studies, the metal chelates of 5-amino-l,3,4-thiadiazoIe-2-thiol are shown to be stable up to 200 °C and undergo one-step decomposition to the free metal (82MI42700). 

Thermogravimetric studies have displayed that the cyclic fragment causes a considerable effect on carbosiloxane copolymer at n= 2 only, and at n=23 no effect of cyclic fragment on the glass transition temperature of the copolymer is observed. Figure 5 shows dependence of Tg on the length of dimethylsiloxane unit for cyclolinear carbosiloxane copolymers. 

Thermogravimetric studies of copolymers have shown that at 300°C mass losses do not exceed 3 - 6%, but are regularly increased with temperature. The main destruction process proceeds in the tem-perature range of 450 - 700°C and final mass losses increase with the volume of the cyclic fragment, respectively. 

The copolymers were thermogravimetrically studied with the help of Seteram Co. thermoweighing machine B-60 in argon (at the heating rate of 5 deg/min) with simultaneous selection and analysis of gaseous degradation products, and the effect of introduction of bulky cyclic fragments into the back-bone on their thermal stability was traced. 

X-ray diffraction analysis indicates that oligomers are amorphous systems with the interchain dis-tance equal d 8.64 A. Thermogravimetric studies show that by thermal oxidative stability oligo-mers are behind polyorganocyclotetrasiloxanes only. 

Thermogravimetric studies of cyclolinear copolymers indicate that 1,3-and 1,5-dispositions of hexa-phenylcyclotetrasiloxane fragment cause no difference in mass losses of copolymers. 

Thermogravimetric studies of cyclolinear copolymers have displayed their sufficiently high thermal oxidative stability. For short lengths of dimethylsiloxane unit, initial mass loss is observed at 260 - 280°C and 5% loss at 300°C. Above 750°C no mass loss variation is observed, which is apparently associated with formation of secondary structures. Thermal oxidative stability of copolymers with carbocyclosiloxane fragments in the backbone is similar to that of their pure siloxane analogues. Moreover, thermal oxidative stability of copolymers is decreased with increase of the volume of cyclic carbosiloxane fragment. 

Thermogravimetric studies of carbosiloxane copolymers have indicated 5% mass loss of the corn-pounds in the temperature range of 250 - 260°C. The main degradation process proceeds in the ran-ge of 380 - 630°C, and above 700°C the mass loss is not observed. It is found that thermal oxidative stability of copolymers is decreased with increase of the cyclic fragment volume, i.e. at the transi-tion from cyclic pentasiloxane to hexasiloxane fragments in cyclolinear carbosiloxane copolymer. It is also found that carbosiloxane copolymers with... 

Thermal Studies. Thermogravimetric studies were performed for the testing of these materials. This was... 

A. Marcilla, M. Beltran, and J. A. Conesa, Catalyst addition in polyethylene pyrolysis thermogravimetric study, J. Anal. Appl. Pyrolysis 58-59, 117 (2001). 

K. Gobin and G. Manos Thermogravimetric Study of Polymer Catalytic Degradation Over Microporous Materials Polym. Degrad. Stabil, 86, 225 (2004). 

O. Senneca, P. Salatino and R. Chirone, A fast heating-rate thermogravimetric study of the pyrolysis of scrap tyres. Fuel, 78, 1575-1581 (1999). 

J. A. Conesa et ai., Thermogravimetric studies on the thermal-decomposition of polyethylene, Journai of Anaiyticai and Appiied Pyroiysis, 36, 1-15 (1996). 

Caution. Thermogravimetric studies show that [Zn(NH2-OH)2Cl2] detonates at about 170°. 

Uranium(IV) acetate is stable in dry air, but it is slowly attacked by atmospheric moisture at room temperature. It is insoluble in benzene, alcohol, and ether and is completely hydrolyzed by water. Thermogravimetric studies show that thermal decomposition is complete at 320°. 

Thermogravimetric Studies on Catalytic and Noncatalytic Pyrolysis of Pitch Derived from Hydrocracked Athabasca Bitumen... 

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