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To characterize a set of synthetic resins, a methodology by pyrolysis-gas chromatography/mass spectrometry (PyGC/MS) has been developed. The studied reference materials were commercial versions of a wide range of synthetic resins. For each polymer, the pyrolytic and chromatographic conditions were optimized to adequately resolve the fragment mixture in a short time. The proposed analytical method does not require previous treatment of the sample, and due to its high sensitivity, only a small sample quantity in the microgram range can be used. The pyrolysis temperature was found to have little effect on the obtained pyrograms. The summarized data set for the individual polymer materials, especially the characteristic fragments with a structure close to the monomeric unit, was useful to identify commercial synthetic resins. These materials were used in the art and conservation field, as binding media, paint additives, painting varnishes, coatings, or consolidants. Two case studies are introduced where direct Py-GC/MS and thermally assisted hydrolysis and methylation GC/MS were applied on art objects: first, a modern gluing material of a medieval reverse glass painting, and the second example, the binding medium of a painting by Georg Baselitz ('Senta', 1992/1993) from the Sammlung Moderne Kunst at the Pinakothek der Moderne, Munich.

A methodology for quantifying calcium carbonate (875 and 712 cm−1) and silica (798 and 779 cm−1) by FTIR spectroscopy applying the constant ratio method is proposed. The studied method is applied for quantitative analysis of calcite and quartz in geological samples. The suggested method uses potassium ferricyanide (2115 cm−1) as standard and samples are prepared as potassium bromide pellets, with statistically satisfactory results (relative standard deviation less than 5%). The influence of particle size (pulverised samples) on the accuracy of the results found by FTIR spectroscopy applying the constant ratio method has been studied. The granulometric study suggests that the homogeneity of particle size is important. An absorbances correction method is proposed to correct spectral interferences. Due to the fact that most spectra are characterised by a high number of absorbance peaks, spectral interferences may occur so that some peaks cannot be used for quantitative analysis. These interferences can be evaluated and eliminated with the proposed method and the peaks can be used in the analysis. [Copyright &y& Elsevier]