Thermogravimetric analysis metals

The process known as transimidization has been employed to functionalize polyimide oligomers, which were subsequentiy used to produce polyimide—titania hybrids (59). This technique resulted in the successhil synthesis of transparent hybrids composed of 18, 37, and 54% titania. The effect of metal alkoxide quantity, as well as the oligomer molecular weight and cure temperature, were evaluated using differential scanning calorimetry (dsc), thermogravimetric analysis (tga) and saxs. 

Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) are also very useful tools for the characterization of polymers. TGA and DSC provide die information about polymer stability upon heating and thermal behaviors of polymers. Most of the polymers syndiesized via transition metal coupling are conjugated polymers. They are relatively stable upon heating and have higher Tgs. 

Au and AuPt nanoparticles were assembled on carbon black (XR-72C) or silica powders with a controlled weight ratio of the metals (Au or AuPt) vs. the support materials. The actual loading was determined by thermogravimetric analysis (TGA) and DCP-AES analysis. 

The section Analysis starts with elemental composition of the compound. Thus the composition of any compound can be determined from its elemental analysis, particularly the metal content. For practically all metal salts, atomic absorption and emission spectrophotometric methods are favored in this text for measuring metal content. Also, some other instrumental techniques such as x-ray fluorescence, x-ray diffraction, and neutron activation analyses are suggested. Many refractory substances and also a number of salts can be characterized nondestructively by x-ray methods. Anions can be measured in aqueous solutions by ion chromatography, ion-selective electrodes, titration, and colorimetric reactions. Water of crystallization can be measured by simple gravimetry or thermogravimetric analysis. 

The fresh and spent catalysts were characterized with the physisorption/chemisorption instrument Sorptometer 1900 (Carlo Erba instruments) in order to detect loss of surface area and pore volume. The specific surface area was calculated based on Dubinin-Radushkevich equation. Furthermore thermogravimetric analysis (TGA) of the fresh and used catalysts were performed with a Mettler Toledo TGA/SDTA 851e instrument in synthetic air. The mean particle size and the metal dispersion was measured with a Malvern 2600 particle size analyzer and Autochem 2910 apparatus (by a CO chemisorption technique), respectively. 

Tanaka, M., Shono, T., Shinra, K. Thermogravimetric analysis and gas chromatography of rare-earth-metal chelates of trifluoroacetylpivaloylmethane (1,1,1 -triflu oro5-5-dimethy 1-hexane-2,4-dione). Anal. Chim. Acta 43, 157 (1968). 

The smaller diameter carbon nanotubes are known to be less stable than their larger diameter counterparts and tend to oxidize at lower temperatures. Amorphous carbon and carbon nanotubes with defects undergo combustion at lower temperatures, in Figure 4, we show the thermogravimetric analysis (TGA) curves of undoped as well as N- and B-doped DWNTs. The decomposition temperatures of all these doped DWNTs are comparable to but slightly lower that the decomposition temperature of pure DWNTs. Derivative TGA curves also shows the same trend. The slight increase in mass at high temperature may be due to the small metallic impurity. 

Table 6. Thermal stability of metal-poly-yne polymers (measured by thermogravimetric analysis at heating rate of 5 °Omin)...

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