Consolidation of waterlogged archaeological wood
Long underwater burials and soaking lead to biological damage and the degradation of water-soaked archaeological wood. The content of the most important cell wall components (cellulose, hemicellulose and lignin) inevitably changes, which leads to a weakening of the strength and hardness and to changes in the chemical composition of the wood. These irreversible changes lead to more defects and ultimately to a significant reduction in the mechanical properties of the wood itself. When the water-saturated wood is allowed to dry, the water evaporates rapidly and leads to the collapse of the cell wall at the microstructural level or even to irreversible shrinkage and deformation at the macroscopic level due to surface tension. The preservation of water-impregnated archaeological wood requires the use of appropriate dehydration and reinforcement techniques to prevent wood relics from shrinking and breaking in order to preserve as much of their original historical appearance as possible. There are three main objectives for the conservation of archaeological wood. The ﬁrst to ﬁnd is a way to remove the excess water in the wood, but to avoid shrinkage or deformation. The second objective is to impregnate the wood with a material that replaces water and gives the wood lasting mechanical stability. Finally, the treatment process should be reversible. It is expected that the use of water-soluble cellulose ethers in combination with nanocellulose will simultaneously achieve these objectives.