Thermal degradation of polystyrene-II the role of abnormalities

✍ Scribed by G.G. Cameron; G.P. Kerr

• Publisher: Elsevier Science
• Year: 1970
• Tongue: English
• Weight: 634 KB
• Volume: 6
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(70)90174-6

✦ Synopsis

The degradation characteristics of thermally synthesized polystyrenes, decomposing at sub-volatilization temperatures in the presence of an inhibitor (1,4-diaminoanthraquinone), support the theory that the weak spots in these polymers are distributed at random within the polymer backbone, rather than at chain ends. Transfer reactions do not appear to be significant at these low temperatures. The evidence indicates that these "weak links" are not head-to-head bonds, branch points or unsaturated structures. However, such thermolabile abnormalities (particularly the last-mentioned) reduce the pyrolytic stability of thermal polystyrenes relative to "living" anionic polymers by lowering the overall activation energy for bond rupture in the phase of decomposition immediately after "weak link" scission. It is possible that the labile structures which decompose in the initial stage of degradation are oxygenated groups, probably peroxide links, but their identity has not been unequivocally proved.