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Abstract  

Hyperbranched epoxy resin (HTDE) has relatively low viscosity and high molecular mass and holds great promise as a functional additive for enhancing the strength and toughness of thermosetting resins. In this work, the curing and thermal degradation kinetics of HTDE/diglycidyl ether of bisphenol-A epoxy (DGEBA) hybrid resin were studied in detail using differential scanning calorimetry (DSC) and thermogravimetric analysis (TG) techniques by Coats–Redfern model. The effect of molecular mass or generation and content of HTME on the activation energy, reaction order, and curing time were discussed; the results indicated that HTDE could accelerate the curing speed and reduce the activation energy and reaction order of the curing reaction.

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/PHAs blends, the thermal degradation behavior of these blends has been little studied [ 4 , 8 , 9 , 12 , 13 ]. The thermal degradation process of the polymer blends is influenced by the degradation conditions, structure of the components of the polymer

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Abstract  

The thermal degradation of a sort of polyvinyl chloride was investigated. Complex processes for polyvinyl chloride degradation were evidenced. The kinetic analysis of dehydrochlorination and of subsequent processes was carried out. A change of mechanism was detected when dehydrochlorination goes to completion. The values of non-isothermal kinetic parameters determined by various methods are in a satisfactory agreement. The obtained results allowed some clarifications concerning the thermal degradation steps.

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Iron polymethacrylate was synthesized by free radical solution polymerization of methacrylic acid, followed by replacement of the carboxylic proton with iron. Thermal volatilization analysis and thermogravimetry were used to study its thermal stability from ambient temperature up to 500oC. The results reveal that ferric oxide is left as residue at the end of the thermal degradation experiments.

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Journal of Thermal Analysis and Calorimetry
Authors:
M. V. Alonso
,
M. Oliet
,
J. C. Domínguez
,
E. Rojo
, and
F. Rodríguez

degradation of resol resins is an important research topic, specifically their heat resistance, thermal stabilization, and degradation kinetics. Many attempts have been made to monitor the thermal degradation of phenol–formaldehyde (PF) resins using

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Abstract  

The thermal degradation of cotton cellulose treated with chemical mixtures containing P and N was studied by thermal analysis, infrared spectroscopy, Char yield and limiting-oxygen-index (LOI). Our experiments demonstrated the following facts. The temperatures and activation energies of pyrolysis were lower for cotton cellulose treated with flame retardants than those for untreated samples and the values of Char yield and LOI were greater for treated cotton than those for untreated one.

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Journal of Thermal Analysis and Calorimetry
Authors:
M. Villetti
,
J. Crespo
,
M. Soldi
,
A. Pires
,
R. Borsali
, and
V. Soldi

Abstract  

The thermal degradation of sodium hyaluronate, xanthan and methylcellulose was evaluated by thermogravimetric and infrared analysis. Kinetic parameters such as activation energy and pre-exponential factor were determined considering the Ozawa and Freeman–Carroll methods. The results suggest changes in the degradation mechanism with the fraction of mass loss for both the studied polysaccharides. The activation energy values determined by the Freeman–Carroll method are higher than those obtained by the Ozawa method under the same conditions, probably because in the first method a first order reaction was assumed and the thermal history effects were eliminated since only one TG curve was used to determine the kinetic parameters. Low thermal stability was observed for polyanions e.g. sodium hyaluronate (Na-Hy) and xanthan(XT) in comparison with methylcellulose (MC) which is a neutral polysaccharide. By infrared spectroscopy, it was observed that at low temperatures there occured only the scission of the exocyclic groups for both polysaccharides and that the scission of strong links in the backbone occurred at high temperatures, in agreement with the kinetic parameters determined for the degradation reaction.

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(IFR) for ABS. The melting point of PPTA was higher than its initial decomposition temperature (266 °C), it could not melt during process and disperse in ABS like inorganic particles. The thermal degradation behaviour and flammability properties of IFR

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/matrix compatibilization on the kinetic parameters of the thermal degradation of NFR composites. In particular, Kim et al. [ 15 ] report results on the activation energy of the thermal decomposition of poly(propylene) (PP)- and high-density poly(ethylene) (HDPE

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Thermal degradation of ethylene (vinyl acetate)

Kinetic analysis of thermogravimetric data

Journal of Thermal Analysis and Calorimetry
Authors:
M. L. Marín
,
A. Jiménez
,
J. López
, and
J. Vilaplana

Ethylene (vinyl acetate), EVA, is a copolymer which is thermally degraded at high temperatures, with acetic acid release at approximately 620 K. This release can be studied by using thermal methods, and in particular thermogravimetric analysis.

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