Pyrolysis gas chromatography mass spectrometry investigation of a thermally cured polymer

The curing of the Matrimid 5292(R) polyimide system was studied by pyrolysis-gas chromatography/mass spectrometry. Pyrolysis products characteristic of both initial components and the cured polymer were identified. Changes in the pattern of pyrolysis products could be related to the progress of polymerization. Amounts of methylphenol isomers (m/z 108), 4-succinimido-4'-aminodiphenylmethane (m/z 265), and 2-(2-propenyl)-4-methylphenol were found to increase as degree of cure increases. Amounts of O,O'-diallyl bisphenol A (m/z 293) produced by pyrolysis decreased with increasing cure. Principal component and canonical variate analysis were used to visualize systematic trends in selected ion intensities from the pyrolysis data. Loading weights derived from orthogonal canonical variate analysis were also found to be useful in identifying pyrolysis products related to percentage cure. These results support the use of Py-GC/MS for monitoring the degree of cure of polymer systems. (C) 1998 Elsevier Science B.V. All rights reserved.