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stearic acid adsorbed on calcium montmorillonite Thermal analysis The thermogravimetric analysis of sodium montmorillonites and calcium montmorillonite are shown in Fig. 2 a and b. The

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Introduction Thermogravimetric analysis is a very useful technique to measure the combustion rate of a solid under well defined conditions such as temperature and oxygen concentration [ 1 – 6 ]. The accuracy of the weight loss

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investigated by thermogravimetric analysis. The carbonisation temperatures were determined from thermogravimetry (TG) results. The effect of carbonisation temperatures on nanoporous characteristics of ACF was then studied. Experimental

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of ochres used in bark paintings. Thermogravimetric analysis (TG) combined with differential scanning calorimetry (DSC) and mass spectrometry (MS) has been used to examine paint obtained from an indigenous bark painting provided by the Australian

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. Fig. 2 XRD pattern of Mg/Al LDH after thermal activation with references of possible phases Thermal analysis Thermogravimetric analysis was performed on

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Abstract  

The thermal degradation of a fully cured polycyanurate thermosetting material was examined by monitoring the mass loss at various temperatures ranging from 200 to 220‡C. The effect of the copper naphthenate catalyst, generally used to facilitate curing, is also studied. A decrease in weight is observed with increasing time at elevated temperatures in the systems containing copper naphthenate, with the onset of degradation occurring sooner with higher concentrations of the copper compound. The apparent activation energy for degradation is 220±30 kJ mol−1.

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Abstract  

In this work the thermal properties of chitins of different origin were compared using a thermogravimetric technique. The αsr method, which makes possible a comparison of the thermal resistances of materials with similar thermostability, was used. The basic range of thermal conversion was determined. In this range, the thermal resistance depends on the chitin origin. The value of activation energy was calculated. No influence on the average molecular mass, crystallinity and the degree of acetylation on the thermal resistance was observed. On the other hand, it was found that the thermal stability depends on the size and perfection of crystallites as well as on the crystalline form of the chitin.

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Journal of Thermal Analysis and Calorimetry
Authors: I. A. Letyanina, N. N. Smirnova, A. V. Markin, V. A. Ruchenin, V. N. Larina, V. V. Sharutin, and O. V. Molokova

differential scanning calorimetry and thermogravimetric analysis. Experimental Sample Tetraphenylantimony acetophenoneoxymate Ph 4 SbONCPhMe (gross formula C32H28Sb1O1N1) ( I ) was prepared in the Chemistry

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Abstract  

Thermal degradation kinetics of copolymers based on bis-phenol A ethoxylated dimethacrylate (Bis-EMA) with triethylene glycol dimethacrylate (TEGDMA), and urethane dimethacrylate (UDMA) with TEGDMA in wt/wt ratios 30/70, 50/50, or 70/30 were investigated using thermogravimetric analysis as a means to provide specific information regarding the internal structures of these resins. Thermogravimetric scans were taken at four different heating rates to perform an isoconversional analysis to determine the change of the effective activation energy as a function of conversion. A two-step degradation mechanism was found to occur in almost all copolymer compositions attributed to the existence of inhomogeneities in the macromolecular structure and the formation of weak links inside the polymeric network.

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