Study of the thermal oxidation of polyolefines—IX: Some differences in the oxidation of polyethylene and polypropylene

✍ Scribed by M. Iring; S. László-Hedvig; K. Barabás; T. Kelen; F. Tüdős

• Publisher: Elsevier Science
• Year: 1978
• Tongue: English
• Weight: 254 KB
• Volume: 14
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(78)90065-4

✦ Synopsis

In the thermal oxidations of polyethylene (PE) and polypropylene (PP), both similarities and differences are found. In the initial stage, the ratio of the hydroperoxide formed and the amount of oxygen absorbed is independent of both the nature of the polymer and the actual reaction conditions. With increased conversion, however, this ratio decreases to a greater extent in the case of PE than for PP. Most of the carbonyl groups formed in the PE chain during oxidation are ketones and carboxyls, but in PP there are also carbonyls with different structure. The amount of carbonyl groups in PE is approximately 1.5 times that observed for PP. The number of scissions involving considerable molecular weight decrease is higher for PE than for PP: for identical conversions, the ratio of scissions is SpE/spp ~ 6.