Evaluation of effects of thymolphthalein on thermooxidative stability of polypropylene

Document Type : Original research

Authors

1 Department of Polymer Engineering, South Tehran Branch, Islamic Azad University, Tehran, Iran

2 Department of Polymer Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran

Abstract

The present work is aimed to find a new and efficient type of antioxidants for polypropylene. Hence, effects of 3,3-bis(4-hydroxy-2-methyl-5-propan-2-ylphenyl)-2-benzofuran-1-one, generally known as thymolphthalein, on thermo-oxidative stability of polypropylene in solid and melt states were evaluated and compared with those of SONGNOX 1010, an efficient commercially used antioxidant for the polymer. Oven ageing experiments followed by Fourier transform infrared (FTIR) spectroscopy showed that thymolphthalein increased thermo-oxidative stability of the polymer outstandingly in the solid state and its stabilization efficiency was comparable to that of SONGNOX 1010. In addition, measurements of oxidative induction time (OIT) and oxidation onset temperature (OOT) revealed that thymolphthalein improved thermo-oxidative stability of the polymer in the melt state significantly. It was also observed that thymolphthalein did not interfere with the stabilization action of SONGNOX 1010 in the polymer neither in melt nor in solid state. On the basis of the obtained results, a probable mechanism for the stabilization action of thymolphthalein in the polymer is proposed.

Keywords

Main Subjects


  1. Bertin D, Leblanc M, Marque SRA, Siri D (2010) Polypropylene degradation: Theoretical and experimental investigations. Polym Degrad Stabil 95: 782-791
  2. Gugumus F (2002) Re-examination of the thermal oxidation reactions of polymers 3. Various reactions in polyethylene and polypropylene. Polym Degrad Stabil 77: 147-155
  3. Ying Q, Zhao Y, Liu Y(1991) A study of thermal oxidative and thermal mechanical degradation of polypropylene. Makromol Chem 192: 1041-1058
  4. Wang X, Wang B, Song L, Wen P, Tang G, Hua Y (2013) Antioxidant behavior of a novel sulfur-bearing hindered phenolic antioxidant with a high molecular weight in polypropylene. Polym Degrad Stabil 98: 1945-1951
  5. Voigt W, Todesco R (2002) New approaches to the melt stabilization of polyolefins. Polym Degrad Stabil 77: 397-40
  6. Richaud E, Fayolle B, Verdu J (2011) Polypropylene stabilization by hindered phenols - Kinetic aspects. Polym Degrad Stabil 96: 1-11
  7. Allen N S, Edge M (1992) Fundamentals of polymer degradation and stabilization.3rd ed., Elsevier, 22-51
  8. Marques M, Oliveira R, Araujo R, Amantes B (2014) In situ stabilization of polypropylene by lignin using a Ziegler-Natta catalyst. Polyolefins J 1: 17-24
  9. Kim T H, Oh DR (2004) Melt grafting of maleimides having hindered phenol antioxidant onto low molecular weight polyethylene. Polym Degrad Stabil 84: 499-503
  10. Shi X, Wang J, Jiang B, Yang Y (2013) Hindered phenol grafted carbon nanotubes for enhanced thermal oxidative stability of polyethylene. Polymer 54: 1167-1176
  11. Jahanmardi R, Assempour H (2008) Effects of galbanic acid on thermal and thermo-oxidative stabilities of LLDPE. Iran Polym J 17: 799-806
  12. Sabnis RW (2007) Handbook of acid-base indicators. CRC Press, 361-390
  13. Abbehausen C, Formiga ALB, Sabadini E, Yoshida IVP (2010) A β-cyclodextrin/siloxane hybrid polymer: Synthesis, characterization and inclusion complexes. J Braz Chem Soc 21: 1867- 1876
  14. Jahanmardi R, Pourattar P, Soleimani H, Shohani N (2016) Effects of thymolphthalein on thermo-oxidative stability of high density polyethylene in melt and solid states. Int J Ind Chem, in press
  15. Yang R, Liu Y, Yu J, Wang K (2006) Thermal oxidation products and kinetics of polyethylene composites. Polym Degrad Stabil 91: 1651-1657
  16. Zeynalov E B, Allen N S (2006) Modelling light stabilizers as thermal antioxidants. Polym Degrad Stabil 91: 3390-3396
  17. Mohammadhosseini M, Jahanmardi R (2014) Investigating effect of ferric stearate on stabilization efficiency of a phenolic antioxidant during thermal oxidation of polyethylene. Iran Polym J 23: 801-807