A study of the interaction of mechanically generated polypropylene radicals with phenolic antioxidant in the presence of oxygen by EPR spectroscopy
Article first published online: 10 MAR 2003
Copyright © 1993 John Wiley & Sons, Inc.
Journal of Applied Polymer Science
Volume 48, Issue 10, pages 1843–1851, 10 June 1993
How to Cite
Hloušková, Z., Lustoň, J. and Szöcs, F. (1993), A study of the interaction of mechanically generated polypropylene radicals with phenolic antioxidant in the presence of oxygen by EPR spectroscopy. J. Appl. Polym. Sci., 48: 1843–1851. doi: 10.1002/app.1993.070481018
- Issue published online: 10 MAR 2003
- Article first published online: 10 MAR 2003
- Manuscript Accepted: 16 SEP 1992
- Manuscript Received: 6 MAY 1992
Isotactic polypropylene (iPP) was mechanically degraded in the absence and presence of a phenolic antioxidant at liquid nitrogen temperature in the presence of oxygen. The interaction of the primarily formed iPP macroradicals with oxygen and phenol was studied by EPR spectroscopy in the temperature region between 77 and 303 K at antioxidant concentrations of 0.1, 0.5, and 3.0 wt%. It was found that iPP macroradicals react at low temperature with oxygen, yielding peroxy radicals, and with antioxidant, with a simultaneous formation of phenoxy radicals. The development and decay of all kinds of radicals was studied. The rate constants for peroxy radical decay were determined and the apparent activation energies for the regions of slow and fast decay were calculated. © 1993 John Wiley & Sons, Inc.