Study of the Degradation of an Epoxy/Amine Resin, 2

✍ Scribed by Bénédicte Mailhot; Sandrine Morlat-Thérias; Pierre-Olivier Bussière; Jean-Luc Gardette

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 135 KB
• Volume: 206
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.200400394

✦ Synopsis

Abstract

Summary: The degradation behaviour of a flexible epoxy/amine resin has been studied. The resin, made of DGEBA and polyether diamine (Jeffamine® D2000) has been submitted to photooxidation, photolysis (in absence of oxygen) and thermooxidation experiments. The nature and the mechanism of formation of the products have been previously reported in the first paper of this series. In this paper, the rate of formation of the degradation products and their distribution within the sample are discussed. The change in the rate of degradation observed after 30 h of irradiation in artificial ageing at λ > 300 nm in the presence of oxygen, measured by ATR‐FTIR and UV‐Vis spectrometries, is explained by a large attenuation of light intensity by the chromophoric photoproducts formed. The photooxidation profiles measured by micro‐FTIR showed a heterogeneous distribution of the photoproducts in the first 250 μm of the exposed surface. The formation of these photoproducts is associated to chain scission reactions. This was clearly evidenced by the decrease of stiffness measured by AFM nanoindentations in the same first 250 μm.

Stiffness profiles measured by AFM nanoindentation of a photooxidised epoxy/amine sample.

magnified imageStiffness profiles measured by AFM nanoindentation of a photooxidised epoxy/amine sample.