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Duivenvoorden JR, Caporaletti F, Woutersen S, Keune K, Hermans JJ. Nanoconfined Water Clusters in Zinc White Oil Paint. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2023; 127:19269-19277. [PMID: 37791101 PMCID: PMC10544026 DOI: 10.1021/acs.jpcc.3c04720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 08/31/2023] [Indexed: 10/05/2023]
Abstract
Pigments in oil paint are bound by a complex oil polymer network that is prone to water-related chemical degradation. We use cryo-Fourier-transform infrared spectroscopy and differential scanning calorimetry to study how water distributes inside zinc white oil paint. By measuring water freezing and melting transitions, we show that water-saturated zinc white oil paint contains both liquid-like clustered water and nonclustered water. A comparison of titanium white paint and nonpigmented model systems indicates that water clustering happens near the pigment-polymer interface. The cluster size was estimated in the nanometer range based on the ice melting and freezing temperatures and on the position of the O-D vibration band. As liquid-like water can play a crucial role in the dissolution and transport of ions and molecules, understanding the factors that favor this phenomenon is essential for establishing safe conditions for the conservation of painted works of art.
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Affiliation(s)
- Jorien R. Duivenvoorden
- Van
‘t Hoff Institute for Molecular Sciences, University of Amsterdam Science Park 904, 1098 XH Amsterdam, The Netherlands
- Conservation
& Science, Rijksmuseum Hobbemastraat 22, 1071 ZC Amsterdam, The Netherlands
| | - Federico Caporaletti
- Laboratory
of Polymer and Soft Matter Dynamics, Experimental Soft Matter and
Thermal Physics, Université Libre
de Bruxelles Avenue, Franklin Roosevelt 50, 1050 Brussels, Belgium
| | - Sander Woutersen
- Van
‘t Hoff Institute for Molecular Sciences, University of Amsterdam Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Katrien Keune
- Van
‘t Hoff Institute for Molecular Sciences, University of Amsterdam Science Park 904, 1098 XH Amsterdam, The Netherlands
- Conservation
& Science, Rijksmuseum Hobbemastraat 22, 1071 ZC Amsterdam, The Netherlands
| | - Joen J. Hermans
- Van
‘t Hoff Institute for Molecular Sciences, University of Amsterdam Science Park 904, 1098 XH Amsterdam, The Netherlands
- Conservation
& Science, Rijksmuseum Hobbemastraat 22, 1071 ZC Amsterdam, The Netherlands
- Conservation
& Restoration, Amsterdam School of Heritage, Memory and Material
Culture, University of Amsterdam Turfdraagsterpad 15-17, 1012 XT Amsterdam, The Netherlands
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2
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Vagnini M, Anselmi C, Vivani R, Sgamellotti A. Non-invasive detection of lead carboxylates in oil paintings by in situ infrared spectroscopy: How far can we go? SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 301:122962. [PMID: 37302196 DOI: 10.1016/j.saa.2023.122962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 05/07/2023] [Accepted: 05/30/2023] [Indexed: 06/13/2023]
Abstract
This paper demonstrates the efficacy of portable mid-infrared spectroscopy as a diagnostic tool for revealing the presence of lead carboxylates on artworks, in situ, without sampling. Samples of cerussite and hydrocerussite - the main components of lead white - were separately mixed with linseed oil, and artificially aged in two steps. Their compositional changes have been monitored over time by infrared spectroscopy in two investigation modes: absorption (benchtop instrument) and reflection (portable instrument), and by XRD spectroscopy. Each component of lead white showed different behavior depending on aging conditions, giving important information about the degradation products which are found in real cases. The accordance of results obtained in both modalities demonstrates that portable FT-MIR is a reliable technique for individuating and identifying lead carboxylates directly on paintings. Examples of the efficacy of this application are provided, by studying paintings from the 17th and 18th centuries.
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Affiliation(s)
- M Vagnini
- SMAArt, c/o Dipartimento di Chimica, Università degli Studi di Perugia, via Elce di Sotto 8, I-06123 Perugia, Italy.
| | - C Anselmi
- Istituto CNR di Ricerca sugli Ecosistemi Terrestri (CNR-IRET), via G. Marconi 2, 05010 Porano (TR), Italy
| | - R Vivani
- Dipartimento di Scienze Farmaceutiche, Università degli Studi di Perugia, via Fabretti 48, 06125 Perugia, Italy
| | - A Sgamellotti
- SMAArt, c/o Dipartimento di Chimica, Università degli Studi di Perugia, via Elce di Sotto 8, I-06123 Perugia, Italy; Istituto CNR di Scienze e Tecnologie Chimiche (CNR-SCITEC), c/o Dipartimento di Chimica, Università degli Studi di Perugia, via Elce di Sotto 8, I-06123 Perugia, Italy; Accademia Nazionale dei Lincei, via della Lungara 10, 00165 Rome, Italy
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3
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Hermans J, Helwig K, Woutersen S, Keune K. Traces of water catalyze zinc soap crystallization in solvent-exposed oil paints. Phys Chem Chem Phys 2023; 25:5701-5709. [PMID: 36734512 PMCID: PMC9930726 DOI: 10.1039/d2cp04861b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The crystallization of metal soaps in polymer matrices is a complex process that affects the stability of oil paintings, as well as the properties of commercial ionomer materials. In the context of conservation of paintings, it is crucial to investigate the influence of solvent exposure on such detrimental chemical processes. Using Fourier transform infrared spectroscopy and a polymer model system that contains metastable amorphous zinc soaps, it is shown that water induces zinc soap crystallization, while solvent swelling alone has no effect. In particular fast-diffusing polar organic solvents with water impurities are able to induce extensive crystallization, delivering high concentrations of water quickly deep into paint layers. Finally, it is demonstrated, both with the model system and real oil paint samples, that even with very short solvent exposure times, significant quantities of crystalline zinc soaps are formed. This strong effect of water impurities in common solvents gives reason to be cautious when conservation treatments are being considered for oil paints that contain zinc white or other water-sensitive chemicals.
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Affiliation(s)
- Joen Hermans
- Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands. .,Conservation & Science, Rijksmuseum, Amsterdam, The Netherlands
| | | | - Sander Woutersen
- Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands.
| | - Katrien Keune
- Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands. .,Conservation & Science, Rijksmuseum, Amsterdam, The Netherlands
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Garrappa S, Frøysaker T, Streeton NLW, Hradil D, Platania E, Beltinger K, Caruso F. Micro-spectroscopic study of late 19th-early 20th century tube paints. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 279:121414. [PMID: 35640470 DOI: 10.1016/j.saa.2022.121414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 04/29/2022] [Accepted: 05/18/2022] [Indexed: 06/15/2023]
Abstract
Many issues in the conservation of paintings from the early modern period are still unresolved due to lack of information on paints from the late 19th and early 20th centuries, in particular their production, formulations, and later degradation processes. The inconsistency of the names that paint manufacturers chose for their products furthermore compounds the challenges faced by conservators and chemists wishing to study them. This paper addresses a number of these issues through investigations of commercial tube oil paints from a paint box owned by the Norwegian painter Harriet Backer (1845-1932). Samples were analyzed using a multi-instrumental approach. Micro-attenuated total reflection Fourier transform infrared spectroscopy and micro-Raman spectroscopy - supported by micro-X-ray powder diffraction - allowed the identification of binders, pigments, and extenders. The data highlight the use of materials that were new at the time and not reported in the manufacturer's catalog. Furthermore, zinc stearate has been detected for the first time. Its detection and the absence of any zinc-based pigments confirms that zinc stearate was already used as dispersing agent in paint formulations at that time.
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Affiliation(s)
- Silvia Garrappa
- Institute of Inorganic Chemistry of the Czech Academy of Sciences, ALMA Laboratory, 250 68 Husinec-Řež, Czech Republic.
| | - Tine Frøysaker
- Department of Archaeology, Conservation, and History (IAKH), Conservation Studies, University of Oslo (UiO), Postboks 1008, Blindern, 0315 Oslo, Norway
| | - Noëlle Lynn Wenger Streeton
- Department of Archaeology, Conservation, and History (IAKH), Conservation Studies, University of Oslo (UiO), Postboks 1008, Blindern, 0315 Oslo, Norway
| | - David Hradil
- Institute of Inorganic Chemistry of the Czech Academy of Sciences, ALMA Laboratory, 250 68 Husinec-Řež, Czech Republic; Academy of Fine Arts in Prague, ALMA Laboratory, U Akademie 4, 170 22 Prague 7, Czech Republic
| | - Elena Platania
- Department of Archaeology, Conservation, and History (IAKH), Conservation Studies, University of Oslo (UiO), Postboks 1008, Blindern, 0315 Oslo, Norway; Norwegian Institute for Cultural Heritage Research (NIKU), Storgata 2, 0155 Oslo, Norway
| | - Karoline Beltinger
- Swiss Institute for Art Research (SIK-ISEA), Department of Art Technology, Zollikerstrasse 32, 8032 Zurich, Switzerland
| | - Francesco Caruso
- Department of Archaeology, Conservation, and History (IAKH), Conservation Studies, University of Oslo (UiO), Postboks 1008, Blindern, 0315 Oslo, Norway; Swiss Institute for Art Research (SIK-ISEA), Department of Art Technology, Zollikerstrasse 32, 8032 Zurich, Switzerland
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Vislavath P, Billa S, S P, Bahadur J, Sudarshan K, Patro TU, Rath SK, Ratna D. Heterogeneous Coordination Environment and Unusual Self-Assembly of Ionic Aggregates in a Model Ionomeric Elastomer: Effect of Curative Systems. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Prakash Vislavath
- Polymer Division, Naval Materials Research Laboratory, Ambernath, Maharashtra 421506, India
| | - Srikanth Billa
- Polymer Division, Naval Materials Research Laboratory, Ambernath, Maharashtra 421506, India
| | - Praveen S
- Polymer Division, Naval Materials Research Laboratory, Ambernath, Maharashtra 421506, India
| | - Jitendra Bahadur
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - Kathi Sudarshan
- Radio Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - T. Umasankar Patro
- Department of Metallurgical & Materials Engineering, Defence Institute of Advanced Technology, Pune, Maharashtra 411025, India
| | - Sangram K. Rath
- Polymer Division, Naval Materials Research Laboratory, Ambernath, Maharashtra 421506, India
| | - Debdatta Ratna
- Polymer Division, Naval Materials Research Laboratory, Ambernath, Maharashtra 421506, India
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Modelling the Interaction between Carboxylic Acids and Zinc Oxide: Insight into Degradation of ZnO Pigments. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27113362. [PMID: 35684300 PMCID: PMC9181975 DOI: 10.3390/molecules27113362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 05/11/2022] [Accepted: 05/17/2022] [Indexed: 11/28/2022]
Abstract
Computational modelling applied to cultural heritage can assist the characterization of painting materials and help to understand their intrinsic and external degradation processes. The degradation of the widely employed zinc oxide (ZnO)—a white pigment mostly used in oil paints—leads to the formation of metal soaps, complexes of Zn ions and long-chain fatty acids coming from the degradation of the oil binder. Being a serious problem affecting the appearance and the structural integrity of many oil paintings, it is relevant to characterize the structure of these complexes and to understand the reaction pathways associated with this degradation process. Density functional theory (DFT) calculations were performed to investigate the adsorption of the acetate and acetic acid on relatively large ZnO clusters and the formation of Zn–acetate complexes. Carboxylic acids with longer alkyl chains were then investigated as more realistic models of the fatty acids present in the oil medium. In addition, DFT calculations using a periodic ZnO slab were performed in order to compare the obtained results at different levels of theory. Optimization calculations as well as the formation energies of the ZnO@carboxylate coupled systems and the thermodynamics leading to possible degradation products were computed. Our results highlight the potential for DFT calculations to provide a better understanding of oil paint degradation, with the aim of contributing to the development of strengthening and conservation strategies of paintings.
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Vannoni L, Pizzimenti S, Caroti G, La Nasa J, Duce C, Bonaduce I. Disclosing the chemistry of oil curing by mass spectrometry using methyl linoleate as a model binder. Microchem J 2022. [DOI: 10.1016/j.microc.2021.107012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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8
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Grøntoft T. The influence of photochemistry on outdoor to indoor NO 2 in some European museums. INDOOR AIR 2022; 32:e12999. [PMID: 35225381 PMCID: PMC9305208 DOI: 10.1111/ina.12999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 12/22/2021] [Accepted: 01/24/2022] [Indexed: 06/14/2023]
Abstract
This paper reports 1 year of monthly average NO2 indoor to outdoor (I/O) concentrations measured in 10 European museums, and a simple steady-state box model that explains the annual variation. The measurements were performed in the EU FP5 project Master (EVK-CT-2002-00093). The work provides extensive documentation of the annual variation of NO2 I/O concentration ratios, with ratios above unity in the summer, in situations with no indoor emissions of NO2 . The modelling included the most relevant production and removal processes of NO2 and showed that the outdoor photolysis was the probable main explanation of the annual trends in the NO2 I/O concentration ratios.
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Nardelli F, Martini F, Lee J, Lluvears-Tenorio A, La Nasa J, Duce C, Ormsby B, Geppi M, Bonaduce I. The stability of paintings and the molecular structure of the oil paint polymeric network. Sci Rep 2021; 11:14202. [PMID: 34244532 PMCID: PMC8270892 DOI: 10.1038/s41598-021-93268-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 06/11/2021] [Indexed: 02/06/2023] Open
Abstract
A molecular-level understanding of the structure of the polymeric network formed upon the curing of air-drying artists' oil paints still represents a challenge. In this study we used a set of analytical methodologies classically employed for the characterisation of a paint film-based on infrared spectroscopy and mass spectrometry-in combination with solid state NMR (SSNMR), to characterise model paint layers which present different behaviours towards surface cleaning with water, a commonly applied procedure in art conservation. The study demonstrates, with the fundamental contribution of SSNMR, a relationship between the painting stability and the chemical structure of the polymeric network. In particular, it is demonstrated for the first time that a low degree of cross-linking in combination with a high degree of oxidation of the polymeric network render the oil paint layer sensitive to water.
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Affiliation(s)
- Francesca Nardelli
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy
| | - Francesca Martini
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy
- Centro Per L'Integrazione Della Strumentazione Scientifica Dell'Università Di Pisa (CISUP), Lungarno Pacinotti 43, 56126, Pisa, Italy
| | - Judith Lee
- Conservation Department, Tate, Millbank, London, SW1P 4RG, UK
| | - Anna Lluvears-Tenorio
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy
| | - Jacopo La Nasa
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy
| | - Celia Duce
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy
| | - Bronwyn Ormsby
- Conservation Department, Tate, Millbank, London, SW1P 4RG, UK
| | - Marco Geppi
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy
- Centro Per L'Integrazione Della Strumentazione Scientifica Dell'Università Di Pisa (CISUP), Lungarno Pacinotti 43, 56126, Pisa, Italy
| | - Ilaria Bonaduce
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy.
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10
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Hermans J, Helwig K. The Identification of Multiple Crystalline Zinc Soap Structures Using Infrared Spectroscopy. APPLIED SPECTROSCOPY 2020; 74:1505-1514. [PMID: 33035076 DOI: 10.1177/0003702820935183] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The formation of crystalline zinc soaps (zinc salts of fatty acids) in oil paint layers is a common sign of paint degradation. In this study, we have used infrared spectroscopy to systematically identify differences in structure and composition of crystalline zinc soap phases, and report data analysis methods for structure attribution in challenging oil paint samples. Supported by reported crystal structures, it was possible to distinguish two distinct types of zinc soap geometry: a highly symmetrical packing for long-chain saturated soaps (type B) and an alternating packing for zinc soaps with short, unsaturated, or dicarboxylic chains (type A). These two types of packing can be identified by a single or split asymmetric COO stretch vibration band. With this new information, we studied the structure and composition of zinc soaps formed in a zinc white model paint and in a cross-section from the painting Equations in Space by Lawren Harris. Using non-negative matrix factorization, band integration and band position maps, it was possible to clearly identify zinc azelate in the model paint and map its spatial distribution. The same methods showed that the paint cross-section contained both types of zinc soap structure within the same paint layer, with the less symmetrical structure appearing only at the interface with the ground layer. The results give valuable information on the internal chemistry of oil paint layers, and the demonstrated methods can find widespread application for in-depth analysis of infrared microscopy data.
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Affiliation(s)
- Joen Hermans
- Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands
- Conservation & Science, Rijksmuseum, Amsterdam, The Netherlands
| | - Kate Helwig
- Canadian Conservation Institute, Ottawa, Canada
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Garrappa S, Kočí E, Švarcová S, Bezdička P, Hradil D. Initial stages of metal soaps` formation in model paints: The role of humidity. Microchem J 2020. [DOI: 10.1016/j.microc.2020.104842] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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12
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Baij L, Buijs J, Hermans JJ, Raven L, Iedema PD, Keune K, Sprakel J. Quantifying solvent action in oil paint using portable laser speckle imaging. Sci Rep 2020; 10:10574. [PMID: 32601362 PMCID: PMC7324590 DOI: 10.1038/s41598-020-67115-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 05/26/2020] [Indexed: 01/30/2023] Open
Abstract
The exposure of oil paintings to organic solvents for varnish removal or to water for the removal of surface dirt can affect the chemical and physical properties of oil paint in an undesired way. Solvents can temporarily plasticise and swell the polymerised oil paint binding medium, enhancing both the thermal mobility and mechanical displacement of pigments embedded in this film. The enhancement of these microscopic motions can affect both the chemical and physical stability of the object as a whole. In order to minimise solvent exposure during cleaning, an analytical method that can quantitatively measure the microscopic motions induced by solvent uptake, is required first. In this study, we use Fourier Transform Laser Speckle Imaging (FT-LSI) and a newly developed portable FT-LSI setup as highly resolved motion detection instruments. We employ FT-LSI to probe pigment motion, with high spatiotemporal resolution, as a proxy for the destabilising effects of cleaning solvents. In this way, we can study solvent diffusion and evaporation rates and the total solvent retention time. In addition, qualitative spatial information on the spreading and homogeneity of the applied solvent is obtained. We study mobility in paint films caused by air humidity, spreading of solvents as a result of several cleaning methods and the protective capabilities of varnish. Our results show that FT-LSI is a powerful technique for the study of solvent penetration during oil paint cleaning and has a high potential for future use in the conservation studio.
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Affiliation(s)
- Lambert Baij
- University of Amsterdam, Van 't Hoff Institute for Molecular Sciences, PO box 94720, 1090GD, Amsterdam, The Netherlands.
- Rijksmuseum, Conservation and Science, PO box 74888, 1070DN, Amsterdam, The Netherlands.
| | - Jesse Buijs
- Wageningen University and Research, Department of Physical Chemistry and Soft Matter, Wageningen, The Netherlands.
| | - Joen J Hermans
- University of Amsterdam, Van 't Hoff Institute for Molecular Sciences, PO box 94720, 1090GD, Amsterdam, The Netherlands
- Rijksmuseum, Conservation and Science, PO box 74888, 1070DN, Amsterdam, The Netherlands
| | - Laura Raven
- Rijksmuseum, Conservation and Science, PO box 74888, 1070DN, Amsterdam, The Netherlands
| | - Piet D Iedema
- University of Amsterdam, Van 't Hoff Institute for Molecular Sciences, PO box 94720, 1090GD, Amsterdam, The Netherlands
| | - Katrien Keune
- University of Amsterdam, Van 't Hoff Institute for Molecular Sciences, PO box 94720, 1090GD, Amsterdam, The Netherlands
- Rijksmuseum, Conservation and Science, PO box 74888, 1070DN, Amsterdam, The Netherlands
| | - Joris Sprakel
- Wageningen University and Research, Department of Physical Chemistry and Soft Matter, Wageningen, The Netherlands
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