Characterization of acrylic resins used for restoration of artworks by pyrolysis-silylation-gas chromatography/mass spectrometry with hexamethyldisilazane.
A procedure based on the technique of the pyrolysis-GC/MS has been applied, in this work, in order to determine the composition of synthetic acrylic resins employed in artworks. The method is based on the on line derivatization of these resins using hexamethyldisilazane (HMDS). Results obtained have been compared with those others from direct pyrolysis and in situ thermally assisted hydrolysis and methylation with tetramethylammonium hydroxide (TMAH). Sensitivity using HMDS as derivatising reagent is found similar to that from direct pyrolysis and methylation with TMAH. Better resolution of the most representative peaks has been also obtained. Additionally, this method reduces the formation of free acrylic acid molecules during the pyrolysis process and, in consequence, more simplified and well-resolved chromatograms are obtained. Finally, the reported procedure has been successfully used for characterizing several acrylic-based varnishes and binding media currently used in Fine Arts and real pictorial samples from graffiti performed on a Middle Ages bridge.
Osete-Cortina
Laura
L
Department of Conservation and Restoration of Cultural Goods, Heritage Conservation Institute, Polytechnical University of Valencia, Camino de Vera 14, 46022 Valencia, Spain.
Doménech-Carbó
María Teresa
MT
D000180:Acrylic Resins / Q000737:chemistry*; D001154:Art; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006358:Hot Temperature; D017646:Organosilicon Compounds; D010150:Paint / Q000032:analysis
D000180:Acrylic Resins; D017646:Organosilicon Compounds; C024548:hexamethylsilazane