New Consolidants for the Conservation of Archeological Wood

The preservation of cultural heritage is of great importance worldwide and, as such, has been the focus of an increasing number of research projects in recent years. In spite of considerable efforts around the world, significant problems have arisen with the conservation of many shipwrecks. The most common issues facing conservators are structural instability upon drying and biological degradation stemming from the aquatic flora and fauna active around the excavation site. However, many important artefacts – such as the sixteenth century warship Mary Rose – also suffer from metal ion saturation from degraded bolts and fittings. In most cases Fe3+ is the greatest problem, which catalyses the production of sulfuric and oxalic acid in the waterlogged timbers, adding chemical degradation to the potential conservation issues. Moreover, the Fe3+ also feeds biological degradation by providing bacteria with an iron source for sustained growth. As such, multi-functional consolidants are greatly needed to tackle not only the many-pronged conservation issues already visible, but also to prevent others from evolving over time. This paper discusses the recent successes in the development of such materials from sustainable, bio-based sources and some potential areas for the future development of these tools.

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