Abstract
In order to clarify the effect of thermal degradation on the structure of polypropylene materials, we investigated the changes in molecular weight distribution. The samples of polypropylene were degraded iso-thermally at 190 °C at different time intervals. The molecular weight distribution was significantly changed with thermo-degradation time, and the carbonyl index increased drastically for 40 min degraded samples, where the molecular weight distribution started splitting into two peaks. The results imply that heterogeneous degradation proceeded in this system. Sequentially, the weight distribution of the oligomeric products observed was discussed on the basis of chain scissions; these results indicate that there are some kinetically favored scissions occurring near the oxygen-centered radicals.
Similar content being viewed by others
References
Crawford RJ (ed) (1996) Rotational moulding of plastics, 2nd edn. Research Studies Press Ltd, England, pp 1–12
Billingham NC, Calvert PD (1990) In: Scott G (ed) Development in polymer stabilizations. Applied Science Publishers Ltd, London
Gillen KT, Wise J, Clough RL (1995) General solution for the basic autoxidation scheme. Polym Degrad Stab 47(1):149–161
Commereuc S, Vaillant D, Philippart JL, Lacoste J, Lemaire J, Carlsson DJ (1997) Photo and thermal decomposition of iPP hydroperoxides. Polym Degrad Stab 57(2):175–182
Shyichuk AV, Stavychna DY, White JR (2001) Effect of tensile stress on chain scission and crosslinking during photo-oxidation of polypropylene. Polym Degrad Stab 72(2):279–285
Fayolle B, Audouin L, George GA, Verdu J (2002) Macroscopic heterogeneity in stabilized polypropylene thermal oxidation. Polym Degrad Stab 77(3):515–522
Elvira M, Tiemblo P, Gomez-Elvira JM (2004) Changes in the crystalline phase during the thermo-oxidation of a metallocene isotactic polypropylene. A DSC study. Polym Degrad Stab 83(3):509–518
Suzuki S, Nakamura Y, Hasan ATM K, Liu B, Terano M, Nakatani H (2005) Dependence of tacticity distribution in thermal oxidative degradation of polypropylene. Polym Bull 54:311–319
Achimsky L, Audouin L, Verdu J, Rychly J, MatisovaRychla L (1997) On a transition at 80 °C in polypropylene oxidation kinetics. Polym Degrad Stab 58(3):283–289
Bertin D, Leblanc M, Marque SRA, Siri D (2010) Polypropylene degradation: theoretical and experimental investigation. Polym Degrad Stab 95(5):782–791
Cramez MC, Oliveira MJ, Crawford RJ (2002) Optimisation of rotational moulding of polyethylene by predicting antioxidant consumption. Polym Degrad Stab 75(2):321–327
Ciolacu CF, Choudhury NR, Dutta DK (2006) Colour formation in poly(ethylene terephthalate) during melt processing. Polym Degrad Stab 91(4):875–885
Oliveira MJ, Botelho G (2008) Degradation of polyamide 11 in rotational moulding. Polym Degrad Stab 93(1):139–146
Xu X, Ding Y, Qian Z, Wang F, Wen B, Zhou H, Zhang S, Yang M (2009) Degradation of poly(ethylene terephthalate)/clay nanocomposites during melt extrusion: effect of clay catalysis and chain extension. Polym Degrad Stab 94(1):113–123
Gonzalez-Gonzalez VA, Neira-Velazquez G, Angulo-Sanchez JL (1998) Polypropylene chain scissions and molecular weight changes in multiple extrusion. Polym Degrad Stab 60(1):33–42
Oliveira MJ, Cramez MC, Garcia CB, Kearns MP, Maziers E (2008) Effect of the processing conditions on the microstructure and properties of rotational molded polyamide 11. J Appl Polym Sci 108(2):939–946
Xiang Q, Xanthos M, Miltra S, Patel SH, Guo J (2002) Effect of melt reprocessing on volatile emissions and structural/rheological changes of unstabilized polypropylene. Polym Degrad Stab 77(1):93–102
Dintcheva NT, La Mantia FP, Scaffaro R, Paci M, Acierno D, Camino G (2002) Reprocessing and restabilization of greenhouse films. Polym Degrad Stab 75(3):459–464
Awaja F, Pavel D (2005) Recycling of PET. Eur Polym J 41(7):1453–1477
Ying Q, Zhao Y, Liu Y (1991) A study of thermal oxidative and thermal mechanical degradation of polypropylene. Die Makromol Chem 192(5):1041–1058
Miyagawa E, Tokumitsu K, Tanaka A, Nitta K (2007) Mechanical property and molecular weight distribution changes with photo- and chemical-degradation on LDPE films. Polym Degrad Stab 92(10):1948–1956
Daivd C, Trojan M, Caro A (1992) Photodegradation of polyethylene: comparison of various photoinitiators in natural weathering conditions. Polym Degrad Stab 37(3):233–245
Canevaro SebastiaoV (2000) Chain scission distribution function for polypropylene degradation during multiple extrusions. Polym Degrad Stab 70(1):71–76
Machado AV, Maia JM, Canevarolo SV, Covas JA (2004) Evolution of peroxide-induced thermomechanical degradation of polypropylene along the extruder. J Appl Polym Sci 91(4):2711–2720
Iedema PD, Willems C, Vliet G, Bunge W, Mutsers SMP, Hoefsloot HCJ (2001) Using molecular weight distributions to determine the kinetics of peroxide-induced degradation of polypropylene. Chem Eng Sci 56(12):3659–3669
Shibayama M, Imamura KY, Katoh K, Nomura S (1991) Transparency of recycled polypropylene film. J Appl Polym Sci 42(5):1451–1458
Hinsken H, Moss S, Pauquet JR, Zweifel H (1991) Degradation of polyolefins during melt processing. Polym Degrad Stab 34(1–3):279–293
Lehrle R, Williams R, French C, Hammond T (1995) Themolysis and methanolysis of poly(β-hydroxybutyrate): random scission assessed by statistical analysis of molecular weight distributions. Macromolecular 28(13):4408–4414
Pasquini N (2005) Polypropylene handbook, 2nd edn. Carl Hanser Verlag, Munich, pp 267–271
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Qian, S., Igarashi, T. & Nitta, Kh. Thermal degradation behavior of polypropylene in the melt state: molecular weight distribution changes and chain scission mechanism. Polym. Bull. 67, 1661–1670 (2011). https://doi.org/10.1007/s00289-011-0560-6
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00289-011-0560-6