Thermally assisted hydrolysis and methylation-pyrolysis-gas chromatography/mass spectrometry of light-aged linseed oil

Drying and photooxidative ageing of thin films of linseed oil has been inve stigated under solar light accelerated ageing conditions by means of therma lly assisted hydrolysis and methylation-pyrolysis-gas chromatography/mass s pectrometry. The main pyrolysis product after the ageing process was found to be azelaic acid, in agreement with results reported in literature on nat urally aged samples. The kinetic of azelaic acid formation during degradati on has been determined from the pyrolysis experiments, and the results are fully compatible with those previously obtained by Fourier transform infrar ed spectroscopy. In this work the method for quantitative determination of azelaic acid from aged linseed oil, proposed by Chiavari et al., 1993 [G. C hiavari, G.C. Galletti, G. Lanterna, R. Mazzeo, J. Anal. Appl. Pyrolysis, 2 4 (1993) 227] is shown to be also valid under more strenuous ageing conditi ons than those occurring in typical indoor expositions. (C) 2001 Elsevier S cience B.V. All rights reserved.