CHARACTERIZATION OF ALKYD PAINT MEDIA BY GAS CHROMATOGRAPHY-MASS SPECTROMETRY

Abstract

Alkyd resins, manufactured from polyols, polybasic acids and monobasic fatty acids, may be categorized as oil-modified polyesters. Resin formulators customize the drying and performance properties of alkyd paints either by varying the type and/or stoichiometric proportions of the reactants, or by adding modifiers (for example, styrene, acrylics and isocyanates) during the manufacturing processes. Alkyd resins have been widely used as binding media in virtually all types of paints since the 1940s, having replaced drying oils in many industrial applications. Identification of alkyd paint media is most often accomplished using Fourier-transform infrared spectroscopy (FTIR) or pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS), yet these techniques are semi-quantitative at best. Two GC-MS procedures have been developed for the quantitative analysis of polyol, dibasic acid and fatty acid components. Results from the analysis of various alkyd paints and unpigmented media demonstrate the utility of the procedures in characterizing alkyd paint media.