In the last few decades many new polymers have been synthesized that are now being used in cultural heritage conservation. The physical and chemical properties and the long-term behaviors of these new polymers are determined by the chemical composition of the starting materials used in their synthesis along with the nature of the substances added to facilitate their production. The practical applications of these polymers depend on their composition and form (foam, film, sheets, pressure-sensitive adhesives, heat-seal adhesives, etc.). Some materials are used in restoration works and others for the exhibition, storage and transport of works of art. In all cases, it is absolutely necessary to know their compositions. Furthermore, many different materials that are manufactured for other objectives are also used for conservation and restoration. The technical information about the materials provided by the manufacturer is usually incomplete, so it is necessary to analytically characterize such materials. FTIR spectrometry is widely used for polymer identification, and, more recently, ATR-FTIR has been shown to give excellent results. This paper reports the ATR-FTIR analysis of samples of polymeric materials used in the conservation of artworks. These samples were examined directly in the solid material without sample preparation.

The reproduction of an old recipe to obtain the pigment known as verdigris leads to a complex mixture of hydrated copper(II) acetates containing neutral verdigris and two varieties of basic verdigris. Since the characterization of such mixture is complicated by the lack of reference standards, we complemented our Raman measurements with Fourier transform infrared (FTIR) and X-ray diffraction (XRD) experiments to perform our analysis, which has been compared with available studies. The spectral analysis allowed us to distinguish the different verdigris varieties, with stretching and bending wavenumbers assigned to the following chemical groups: OH groups (OH hydroxy and OH H2O ) (3600-3050 cm −1 ), Cu-O bonds (Cu-O and Cu-OH) (1000-450 cm −1 ) and those corresponding to the acetate group (CH 3 COO − ), i.e. (CH 3 : 3000-2850 cm −1 ) and (COO − : 1600-1400 cm −1 and 700-600 cm −1 ). Both wavenumbers and Raman intensities were used to quantify the relative compositions of the mixture components.

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The term verdigris embraces a wide range of synthetic pigments whose compositions can also vary. All are salts of copper, but their chemical composition will vary depending on the ingredients used to synthesize them and the conditions in which that synthesis is performed.This article presents the results of applying some of the recipes contained in treatises; the recipes used here, specifically, were taken from the Mappae Clavicula (12th century) and the Ms.

The purpose of this work is to provide spectroscopic evidence of possible chemical pathways that took place in the formation of fossil resins Class I. The natural polymerization process is mimicked in the laboratory using pure communic acids (terpene derivatives) as reactants, which were subjected to controlled temperature treatment. We shall focus here on the trans-, cis-and iso-/ mirceo-communic acid isomers, and the temperature-induced reactivity is discussed on the basis of the different arrangements of the conjugated double-bonds moieties in the monomeric units. Transformations starting at 130, 90 and 127°C, for trans-, cisand iso-communic acids, respectively, led to the formation of intermediate products. The whole process was followed and analyzed by micro-Raman spectroscopy. The absence of several Raman signatures suggests conjugation loss in the side-chain of these intermediate compounds. With increasing temperature, the intermediate products suffer additional maturation reactions to form the final fossil resin analogues object of this work.