Semiquantitative analysis of the thermal degradation of polypropylene

• Published in: Journal of applied polymer science 2003-05, Vol.88 (6), p.1465-1472
• Main Authors: Ishikawa, Tomoyuki, Ohkawa, Tomohiro, Suzuki, Masaaki, Tsuchiya, Toshiaki, Takeda, Kunihiko
• Format: Article
• Language: English
• Subjects: Applied sciences; Chemical reactions and properties; Degradation; Exact sciences and technology; flame retardance; Organic polymers; Physicochemistry of polymers; poly(propylene) (PP); simulations
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.11819

The pyrolysis product distributions of polypropylene (PP) were observed, and the experimental data were semiquantitatively analyzed by computer simulation with the Molic mouse method. Studies by many researchers on PP decomposition and experimental results achieved in this study were examined. The product distributions were classified into three types of hydrocarbon products: 3n, 3n + 1, and 3n + 2 (n = monomer unit). The ratio showed the characteristic tendency, and the thermal degradation of PP appeared to include very complicated scission paths. The Molic mouse method, which was applied to the analysis of the thermal rearrangement and decomposition of poly(phenylene ether), was used to simulate the experimental results. After several steps by which the proper model was constructed, the scission probabilities to generate 2 × 3n, 3n + 1 and 3n + 2, 3n and 3n + 1, 3n and 3n + 2, C9, and C15 hydrocarbons were successfully calculated to be 0.25, 0.67, 0.47, 0.35, 1.0, and 0.33, respectively. This meant that the scission process of PP was very simple except for the C9 and C15 generation paths, for which the cyclic compounds were stable intermediates. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1465–1472, 2003