The analysis of synthetic paints by pyrolysis–gas chromatography–mass spectrometry (PyGCMS)

Abstract

This paper describes the application of pyrolysis–gas chromatography–mass spectrometry (PyGCMS) to the characterization of an extensive range of synthetic paint types. Household and industrial paints, both of which have been formulated with polymers such as alkyd, polyvinyl acetate (PVA) and nitrocellulose, are included in this study, in addition to the acrylic solution and acrylic emulsion paints that were made specifically for the artists' market. The pyrograms obtained by PyGCMS were characteristic to each paint type and their principal diagnostic features are discussed. Apart from using the mass spectra produced by electron impact (EI) to confirm the identity of every peak, two additional analytical features of the mass spectrometer were shown to be particularly useful in this study. Chemical ionization (CI) was used to assist with the identification of unknown peaks through molecular weight determination. Selected ion current (SIC) monitoring, where the mass spectrometer only scans for specific masses, was successfully used for the detection of peaks of low intensity or those hidden by a more abundant material with a similar retention time.