Poly thermooxidative degradation

Kozlov, G. V. Shustov, G. B. Zaikov, G. E. Burmistr, M. V. Korenyako V. A. The influence of polymer melt structure on chemical mechanisms of poly ary lateary lene-sulfonoxide melt thermooxidative degradation. Problems of Chemistry and Chemical Technology, 2002(3), 67-72. 

The thermooxidative degradation and SiOx film formation of poly(vinyl imidazole-co-vinyl trimethoxysilane) on copper was investigated. Thermal degradation of the copolymer was catalysed by copper in the film and at the substrate surface. Copper in the copolymer film contributed to the formation of a copper-containing SiOx film during thermal degradation. Copper oxides in the film interacted with the SiOx film to form a copper-rich phase near the film defects and cracks (142). 

Laachachi, A., Ferriol, M., Cochez, M., Ruchand, D., Lopez-Cuesta, J.M. (2008) The catalytic role of oxide in the thermooxidative degradation of poly(methyl... 

It is a support for acidic catalytic species which react with the oxidized products formed via the thermooxidative degradation of the material. So, the intumescent material consists of polyaromatic stacks bridged by polymer links and phosphate (poly-, di- or orthophosphate) groups, as presented in Figure 5. 

In air, the thermooxidative degradation and stability of commercial and laboratory made polyhydroxyalkanoates such as the homopolymer poly(3-hydroxybutyrate) and the copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) was investigated by Carraso et al. [20]. It was indicated that the presence of hydroxyvalerate within the copolymer led to a thermally more stable material (with an increase of 14°C). 

Spanninger, P. A. Thermooxidative Degradation leading to geUed Poly(ethylene terephthalate), Journal of Polymer Science, Polymer Chemistry Edition, 12 (1974) 4S709 717... 

Botelho G, Queirds A, Gijsman P. A comparative study on the mechanism of the thermooxidative degradation of poly(ethylene 2,6-naphta-late) and poly(butylene 2,6-naphthalate). Polym Degrad Stab 2000 70 299-304. 

Beside inhibiting thermooxidative ageing, phosphorus containing additives increase radiation resistance of polyimides and poly(alkyl terephthalates) the rate of evolution of the aromatic ring radiation degradation product - CH4 reduces two-fold. 

The methods of DSC and IR spectroscopy were used to study various blends of poly(3-hydroxybu-tyrate) with ethylene-propylene copolymer rubber (EP). When the weight fractions of the initial pol5miers are equal, a phase inversion takes place as the blends are enriched with EP, the degree of crystallinity of poly(3-hydroxybutyrate) decreases. In blends, the degradation of poly(3-hydroxybutyrate) begins at a lower temperature compared to the pure polymer and the thermooxidative activity of the ethylene-propylene copolymer in the blend decreases in comparison with the pure copolymer. 

Botelho, G., A. Queirds, and P. Gijsman, Thermooxidative studies of polyfether-esters) 1. Copolymer of poly(butylene terephthalate) and polyfethylene oxide). Polymer Degradation and Stability, 67(1) p. 13. 2000. 

In air a thermooxidative mechanism of degradation leads to a higher amount of poly aromatic structures up to about 500°C. However, at higher temperatures, complete volatilization of material occurs, and no residue is observed. 

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