Raman and infrared analysis of glues used for pottery conservation treatments

Abstract

The conservation of ceramics and glass involves the repair or the restoration of broken and fragmented artefacts with polymer adhesives and gap fillers. In the past, many different adhesives had been used. Re-restoration is often required and the fast identification of adhesive residues on objects would be very useful to define the best of way to remove them, in particular to avoid the use of noxious chemicals. Sixteen pottery artefacts restored during the 19th and 20th centuries at the Musée National de Céramique in Sèvres have been analysed by non-destructive Raman microspectroscopy. For comparison purposes, the artefacts were also sampled in order to acquire infrared (IR) absorption spectra in KBr pellets. Modern adhesives (methyl metacrylate/acrylate, vinyl acetate, polychloroprene, methyl 2-cyanoacrylate and diglycidylether biphenol) were also characterised with the same methods. IR and Raman spectra were obtained for all ancient glue residues, but among the 16 analysed items, only 7 adhesives have been identified unambiguously, and an assignment proposed for 4 others solely on the basis of the Raman signature. Copyright © 2009 John Wiley & Sons, Ltd.