Degradation, thermal activation energies for

Because of the complexity of the AOS system, the authors of Ref. 72 state that the determination of the activation energy for thermal degradation might present grave difficulties. They decided to study each of the AOS components separately whereby each was observed to follow a complicated thermal degradation path. 

Stamm has determined the rates and activation energies for thermal degradation of a-cellulose, cotton, rayon, and paper, all of which were found to follow a first-order reaction. A summary of the results obtained on the basis of physical properties is given in Table III. 

Where to, A17, t) are constants for a given fibre, applied stress and Tis the absolute temperature. Zhurkov achieved an excellent correlation between AU calculated from such stress-rupture data and Al/ , the activation energy for thermal degradation for a wide range of fibres. It was also possible to identify the free radicals and degradation products formed... 

This equation was shown to hold for a wide range of polymers and, moreover, the values obtained for Uo correlated very well with values obtained for the activation energy for thermal degradation. 

The variation of the activation energy for thermal degradation (Ea) of the PEN/CNT nanocomposites under nitrogen and air estimated from the Flynn-Wall-Ozawa analysis are presented in Tables 13 and 14, respectively. 

An adaptation of the Arrhenius equation referred to as the Kissinger method [32] was employed for this analysis. Determination of the activation energy for thermal degradation of polycarbonate-acrylonitrile-butadiene-styrene copolymer-montmorillonite composite when compared to the polymer blend without montmorillonite provided a similar trend... 

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