Archeological wood conservation with selected organosilicon compounds studied by XFM and nanoindentation

Abstract

Waterlogged wood conservation is a complex and challenging task. Detailed knowledge about the interactions between the applied chemicals and wood is necessary to ensure the effective and safe conservation of wooden artifacts. The present research aims to determine the mechanism of dimensional stabilization of archeological wood by organosilicon compounds using the combination of synchrotron-based X-ray fluorescence microscopy (XFM) and nanoindentation. Archeological oak wood was treated with methyltrimethoxysilane, (3-mercaptopropyl)trimethoxysilane, or 1,3-bis-[(diethylamino)-3-(propoxy)propan-2-ol]-1,1,3,3-tetramethyldisiloxane, which in previous studies were found to be more effective than other organosilicons in stabilizing wood dimensions. The XFM and nanoindentation results showed that all three organosilicons infiltrated wood cell walls and enhanced their mechanical properties. The XFM also showed that part of the chemicals filled some void spaces like cell lumina. Based on the results obtained here and in our previous research, it is determined that the mechanism of archeological wood dimensional stabilization by organosilicon treatment is complex and likely involves both filling cell lumina and infiltration into cell walls where organosilicons interact with wood polymers.

A multi-technique and multiscale comparative study on the efficiency of conservation methods for the stabilisation of waterlogged archaeological pine

“…These silanes are capable of crosslinking with each other through condensation and with alkoxy bonds present within the wood polymers 40 . In a study by Broda 59 , the mode of action of various organosilicons in the wood structure was examined and aligned with a model proposed by Norimoto 60 . This model indicates that organosilicons have the capability to fill both the cell wall and lumina.…”

The Pivotal Role of Microscopy in Unravelling the Nature of Microbial Deterioration of Waterlogged Wood: A Review

“…[9], which enables large volumes of ancient woods exposed to prolonged anoxic environments to be rapidly scanned/assessed for microbial deterioration without the need for the tedious and time-consuming preparation and imaging processes associated with electron microscopy. Conservators can now take advantage of the information made available on both the physical state and chemical characteristics of heritage wood at tissue and cell wall levels [5,9,138,186] to develop a more targeted approach for improving the quality of preservation of precious heritage wooden objects as they continue to be uncovered, using natural or bio-based compounds [187][188][189] compatible with cell walls and cell wall residues where possible.…”