Thermogravimetric analysis and

Thermogravimetric analysis and other studies made on low-molecular weight model compounds such as 1,3, 5,-trichlorohexane [7,8] corresponding to the idealized head-to-tail structure of PVC show these structures to be considerably more stable than the polymer. This abnormal instability of the polymer is attributed to structural irregularities or defects in the polymer chain, which serve as initiation sites for degradation. 

The thermal degradation of TsHs and other TsRs species (R = Me, /Bu, nCsHiy, Ph) in air and an inert atmosphere has been studied by thermogravimetric analysis and shows that for TsHs incomplete sublimation tends to occur, and, in air, oxidation competes with volatalization. ... 

Both thermogravimetric analysis and differential scanning calorimetric studies were carried out on modified and unmodified PPO samples. Table IV presents the weight losses and the glass transition temperatures of the most representative polymers. 

In this study, we extend the range of inorganic materials produced from polymeric precursors to include copper composites. Soluble complexes between poly(2-vinylpyridine) (P2VPy) and cupric chloride were prepared in a mixed solvent of 95% methanol 5% water. Pyrolysis of the isolated complexes results in the formation of carbonaceous composites of copper. The decomposition mechanism of the complexes was studied by optical, infrared, x-ray photoelectron and pyrolysis mass spectroscopy as well as thermogravimetric analysis and magnetic susceptibility measurements. 

For this purpose, all three catalyst supports were initially synthesized by a chemical vapor deposition (CVD) process and thereafter, using a wet impregnation method, loaded with cobalt as the active component for FTS. The as-synthesized Co/nanocatalysts were then characterized by applying electron microscopic analysis as well as temperature-programmed desorption, chemi- and physisorption measurements, thermogravimetric analysis, and inductively coupled plasma... 

TA instruments has developed automated thermogravimetric analysis and related kinetic programs that enable a rapid determination of decomposition rates to be made. The following excerpt from a TA application brief [57] explains the method ... 

Discuss, the fundamental theory of thermogravimetric analysis , and its instrumentation aspects in an elaborated manner. 

The elemental composition of CuCr204 Cu 27.44%, Cr 44.92%, O 27.64%. The catalyst is analysed by measurement of surface area and pore volume also by differential thermal analysis, thermogravimetric analysis and x-ray studies. 

Acid chlorides in pyridine convert 91 to the tetraamides 96, which, when heated, cleanly extrude 2 mol acid to give the diimidazo[4,5-h 4, 5 -e]-pyrazines (97) in good yield. The temperatures required for the pyrolysis can be readily determined by thermogravimetric analysis, and range from 285°C (97, R = Me) to 420°C (97, R = p-chlorophenyl). Under these conditions, the acid distills leaving analytically pure 97 in most cases (Scheme 35). 

The common methods of investigating the kinetics of explosive reactions are differential thermal analysis, thermogravimetric analysis and differential scanning calorimetry. 

The differential thermal analysis, thermogravimetric analysis, and x-ray results establish that the cationic modifications are stable under the outgassing conditions used in the sorption measurements. 

The efficiency of extraction is determined by thermogravimetric analysis and the extracted surfactant is recrystallized from acetone and re-used for subsequent syntheses. 

Kundu and Bhattacharya14 have isolated dioxouranium complexes of benzohydroxamic acid with the compositions M[U02(C7H602N)3] [where M = Li, Na, K, Cs, Tl, N4, pyH+ (pyridinium) or agH+ (aminoguanidinium)] and M [U02(C7H602N)3]2 [where M = enH2+ (ethylene-diammonium)]. All the complexes, with the exception of the sodium compound, are insoluble in common organic solvents but are soluble in DMSO and DMF. The complexes have been characterized on the basis of electronic, IR and molar conductance data in DMF. Their fairly stable character is indicated by thermogravimetric analysis and the stability order is NH4+ < Tl+ < Cs+ < Li+ w Na+ agH+ < K+ pyH+ < enHl+. 

Box 9.1 Thermogravimetric Analysis and Differential Scanning Calorimetry in the Study of Inclusion Compounds... 

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). 

N-Donor Ligands. Cinchonine forms a 1 2 complex with TiCl3 in which the ligand co-ordinates through the N atom of the heterocyclic ring. The presence of two lattice-held H20 molecules in the complex is indicated by thermogravimetric analysis and i.r. spectroscopy.101... 

The complex K2[Ir(OH)6] can be synthesized by treating Na2[IrCl6] with KOH, and has been characterized by absorption spectroscopy, thermogravimetric analysis and voltage-current curves.464 Cd[Ir(OH)6] possesses a tetragonal structure and serves as a magnetically dilute insulator, while Zn[Ir(OH)6] has a cubic structure and exhibits an anomalous magnetic behaviour.465... 

In another study, Nayak et al. (26) prepared CNSL-novalac resins by condensing cardanyl acrylate with p-aminobenzoic acid and formaldehyde in the presence of an acid catalyst. Thermogravimetric analysis and degradation studies on these resins have been carried out. It was observed that this resin decomposed with the removal... 

The influence of sorbed moisture on chemical stability and the flow and compaction of powders and granulations is well established. The moisture content and hygroscopicity of excipients is particularly important as total product processing as well as finished product stability can be affected. Hygroscopicity, moisture-sorption isotherms, and equilibrium moisture content can be determined by thermogravimetric analysis and Karl Fisher titration methods. 

The precursor and the calcined catalyst were characterized by various techniques such as nitrogen adsorption, mercury porosimetry, X-ray diffraction (XRD), atomic emission spectrometry by inductively coupled plasma (ICP), thermogravimetric analysis, and temperature-programmed reduction (TPR). More details about the catalyst preparation and characterization can be found in a previous work (22). 

Pyrolysis of wheat straw and washed wheat straw has been carried out by simultaneous thermogravimetric analysis and differential scanning calorimetry at heating rates of 5,10 and 40 C/min. 

Recording thermal decomposition curves is called thermogravimetric analysis, and the mass versus temperature curves are termed thermograms. 

Analytical techniques commonly used to check for solid-state characteristics include melting point (including hot-stage microscopy), solid-state infrared spectroscopy, x-ray powder diffraction, thermal analysis (e.g., differential scanning calorimetry, thermogravimetric analysis, and differential thermal analysis), Raman spectroscopy, scanning electron microscopy, and solid-state nuclear magnetic resonance (NMR). 

Peramal VL, Tabburie S, Craig DQM. Characterisation of the variation in the physical properties of commercial creams using thermogravimetric analysis and rheology. Int J Pharm 1997 155 91-98. 

The superconducting oxides La gSr 2Cu04 and I YCujOy were prepared by decomposition of mixed metal nitrates. Thermogravimetric analysis and electron spin resonance measurements indicated the presence of Cu(I) and Cu(III) in the Lai.8Sr.2 u 4 phase. The compound I YC C prepared from the nitrates and subjected to an oxygen anneal at 425°C gave a sharp superconducting transition at 92 K. The phase was stoichiometric but readily decomposed when kept in contact with moist air. 

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