Measurement of diffusion of antioxidants in isotactic polypropylene by isothermal differential thermal analysis

Authors

  • T. Schwarz,

    1. Institut für Chemische und Physikalische Technologie der Kunststoffe (ITK), Montanuniversität Leoben, Franz-Josef-Strasse 18, A-8700 Leoben, Austria
    Search for more papers by this author
  • G. Steiner,

    1. Institut für Chemische und Physikalische Technologie der Kunststoffe (ITK), Montanuniversität Leoben, Franz-Josef-Strasse 18, A-8700 Leoben, Austria
    Search for more papers by this author
  • J. Koppelmann

    1. Institut für Chemische und Physikalische Technologie der Kunststoffe (ITK), Montanuniversität Leoben, Franz-Josef-Strasse 18, A-8700 Leoben, Austria
    Search for more papers by this author

Abstract

The diffusion of the phenolic antioxidant 1,3,5-tris(3,5-di tert-butyl-4-hydroxybenzyl)mesitylene (IRGANOX 1330) in extruded sheets of isotactic polypropylene (iPP) was investigated over the temperature range from 80 to 120°C by isothermal differential thermal analysis (DTA). The measurements showed a clear relation between oxidation induction time and oxidation maximum time (both determined by isothermal DTA) and the concentration of stabilizer. It was possible to calculate the diffusion coefficients and the activation energy of diffusion of IRGANOX 1330 in iPP by measuring the oxidation maximum times across stacks of isotactic polypropylene sheets.

Ancillary