FTIR emission spectroscopy applied to polymer degradation

The thermal degradation of some common polymers was investigated using infrared emission spectroscopy. The potential of the technique to contribute to polymer degradation studies is demonstrated by measuring the spectroscopic changes that occur during thermal degradation, oxidation or decomposition of polymers under air at temperatures ranging from 150 to 250 degrees C. Polymer types studied include EPDM and nitrile rubbers (commercial materials containing some inorganic fillers), PMMA, PAN, PA, PVC and PS. The resulting qualitative changes in the polymers were easily detected, and were correlated with the current knowledge on the degradation mechanisms of these materials. These include simple carbonyl formation and related oxidative reactions, weight loss and volatilization, as well as formation of conjugation and specific polymer reactions. Some fundamental aspects and limitations of the technique are discussed to demonstrate the intrinsic difficulties of attempting to determine precise emittances and ultimately quantitative spectroscopic information. FTIR emission appears to be promising for studying in situ polymer degradation. Published by Elsevier Science Limited.