Thermogravimetric evaluation of the kinetics of decomposition of polyolefin blends

• Published in: Polymer degradation and stability Vol. 61; no. 2; pp. 289 - 295
• Main Authors: Albano, Carmen, de Freitas, Eunice
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.01.1998; Elsevier Science
• Subjects: Applied sciences; Exact sciences and technology; Physical properties; Polymer industry, paints, wood; Properties and testing; Technology of polymers; Thermic properties and inflammability; Scrap polymer; Polymer blends; Property composition relationship; Propylene polymer; High density ethylene polymer; Olefin polymer; Kinetics; Kinetic parameter; Experimental study; Thermal stability; Thermal degradation
• ISSN: 0141-3910; 1873-2321
• DOI: 10.1016/S0141-3910(97)00211-5

The thermodegradative behavior of polypropylene (PP), of non-degraded and degraded high density polyethylene (HDPE) and their blends was studied, in order to analyze their thermal stability. Van-Krevelen (V-K), Coats-Redfern (C-R) and Horowitz-Metzger (H-M) integral methods as well as the Freeman-Carroll (F-C) differential approach were used to determine kinetic parameters. The activation energy ( E a ) obtained for PP mixed with non-degraded HDPE (5 to 50%) is lower than the E a corresponding to pure polymers and does not depend on the HDPE concentration. Blends of degraded materials show an approximate value of E a of 200 kJ/mol for H-M, 160 KJ/mol for V-K and 150 KJ/mol for C-R, for mixtures with concentrations by weight of HDPE up to 20%, but this value decreases drastically with higher concentrations.