Reactivity of Waterlogged Archeological Elm Wood with Organosilicon Compounds Applied as Wood Consolidants: 2D <sup>1</sup>H–<sup>13</sup>C Solution-State NMR Studies
Some organosilicon compounds, including alkoxysilanes and siloxanes, proved effective in stabilizing the dimensions of waterlogged archaeological wood during drying, which is essential in the conservation process of ancient artifacts. However, it was difficult to determine a strong correlation betwe...
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| Format: | Article |
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MDPI AG
2022-05-01
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| Series: | Molecules |
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| Online Access: | https://www.mdpi.com/1420-3049/27/11/3407 |
| _version_ | 1797492562137710592 |
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| author | Magdalena Broda Daniel J. Yelle |
| author_facet | Magdalena Broda Daniel J. Yelle |
| author_sort | Magdalena Broda |
| collection | DOAJ |
| description | Some organosilicon compounds, including alkoxysilanes and siloxanes, proved effective in stabilizing the dimensions of waterlogged archaeological wood during drying, which is essential in the conservation process of ancient artifacts. However, it was difficult to determine a strong correlation between the wood stabilizing effect and the properties of organosilicon compounds, such as molecular weight and size, weight percent gain, and the presence of other potentially reactive groups. Therefore, to better understand the mechanism behind the stabilization effectiveness, the reactivity of organosilicons with wood polymers was studied using a 2D <sup>1</sup>H–<sup>13</sup>C solution-state NMR technique. The results showed an extensive modification of lignin through its demethoxylation and decarbonylation and also the absence of the native cellulose anomeric peak in siloxane-treated wood. The most substantial reactivity between wood polymers and organosilicon was observed with the (3-mercaptopropyl)trimethoxysilane treatment, showing complete removal of lignin side chains, the lowest syringyl/guaiacyl ratio, depolymerization of cellulose and xylan, and reactivity with the C6 primary hydroxyls in cellulose. This may explain the outstanding stabilizing effectiveness of this silane and supports the conclusion that extensive chemical interactions are essential in this process. It also indicates the vital role of a mercapto group in wood stabilization by organosilicons. This 2D NMR technique sheds new light on the chemical mechanisms involved in organosilicon consolidation of wood and reveals what chemical characteristics are essential in developing future conservation treatments. |
| first_indexed | 2024-03-10T01:05:28Z |
| format | Article |
| id | doaj.art-776bc2423d1b409e80b4024388bd761d |
| institution | Directory Open Access Journal |
| issn | 1420-3049 |
| language | English |
| last_indexed | 2024-03-10T01:05:28Z |
| publishDate | 2022-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Molecules |
| spelling | doaj.art-776bc2423d1b409e80b4024388bd761d2023-11-23T14:28:12ZengMDPI AGMolecules1420-30492022-05-012711340710.3390/molecules27113407Reactivity of Waterlogged Archeological Elm Wood with Organosilicon Compounds Applied as Wood Consolidants: 2D <sup>1</sup>H–<sup>13</sup>C Solution-State NMR StudiesMagdalena Broda0Daniel J. Yelle1Department of Wood Science and Thermal Techniques, Faculty of Forestry and Wood Technology, Poznan University of Life Sciences, ul. Wojska Polskiego 38/42, 60-637 Poznan, PolandForest Biopolymers Science and Engineering, Forest Products Laboratory, USDA Forest Service, One Gifford Pinchot Drive, Madison, WI 53726, USASome organosilicon compounds, including alkoxysilanes and siloxanes, proved effective in stabilizing the dimensions of waterlogged archaeological wood during drying, which is essential in the conservation process of ancient artifacts. However, it was difficult to determine a strong correlation between the wood stabilizing effect and the properties of organosilicon compounds, such as molecular weight and size, weight percent gain, and the presence of other potentially reactive groups. Therefore, to better understand the mechanism behind the stabilization effectiveness, the reactivity of organosilicons with wood polymers was studied using a 2D <sup>1</sup>H–<sup>13</sup>C solution-state NMR technique. The results showed an extensive modification of lignin through its demethoxylation and decarbonylation and also the absence of the native cellulose anomeric peak in siloxane-treated wood. The most substantial reactivity between wood polymers and organosilicon was observed with the (3-mercaptopropyl)trimethoxysilane treatment, showing complete removal of lignin side chains, the lowest syringyl/guaiacyl ratio, depolymerization of cellulose and xylan, and reactivity with the C6 primary hydroxyls in cellulose. This may explain the outstanding stabilizing effectiveness of this silane and supports the conclusion that extensive chemical interactions are essential in this process. It also indicates the vital role of a mercapto group in wood stabilization by organosilicons. This 2D NMR technique sheds new light on the chemical mechanisms involved in organosilicon consolidation of wood and reveals what chemical characteristics are essential in developing future conservation treatments.https://www.mdpi.com/1420-3049/27/11/3407archaeological woodsilanesiloxanewood consolidation2D NMRchemical reactivity |
| spellingShingle | Magdalena Broda Daniel J. Yelle Reactivity of Waterlogged Archeological Elm Wood with Organosilicon Compounds Applied as Wood Consolidants: 2D <sup>1</sup>H–<sup>13</sup>C Solution-State NMR Studies Molecules archaeological wood silane siloxane wood consolidation 2D NMR chemical reactivity |
| title | Reactivity of Waterlogged Archeological Elm Wood with Organosilicon Compounds Applied as Wood Consolidants: 2D <sup>1</sup>H–<sup>13</sup>C Solution-State NMR Studies |
| title_full | Reactivity of Waterlogged Archeological Elm Wood with Organosilicon Compounds Applied as Wood Consolidants: 2D <sup>1</sup>H–<sup>13</sup>C Solution-State NMR Studies |
| title_fullStr | Reactivity of Waterlogged Archeological Elm Wood with Organosilicon Compounds Applied as Wood Consolidants: 2D <sup>1</sup>H–<sup>13</sup>C Solution-State NMR Studies |
| title_full_unstemmed | Reactivity of Waterlogged Archeological Elm Wood with Organosilicon Compounds Applied as Wood Consolidants: 2D <sup>1</sup>H–<sup>13</sup>C Solution-State NMR Studies |
| title_short | Reactivity of Waterlogged Archeological Elm Wood with Organosilicon Compounds Applied as Wood Consolidants: 2D <sup>1</sup>H–<sup>13</sup>C Solution-State NMR Studies |
| title_sort | reactivity of waterlogged archeological elm wood with organosilicon compounds applied as wood consolidants 2d sup 1 sup h sup 13 sup c solution state nmr studies |
| topic | archaeological wood silane siloxane wood consolidation 2D NMR chemical reactivity |
| url | https://www.mdpi.com/1420-3049/27/11/3407 |
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