Andrea Casini, Lucia Bucciacchio, Teresa Guaragnone, Damiano Bandelli, Rodorico Giorgi
Iron-based artworks, often exposed to harsh environmental conditions that accelerate degradation, require conservation methods that balance effective cleaning with environmental impact. Traditional cleaning techniques, which rely on aggressive chemical agents, can damage both the artworks and the surrounding environment, highlighting the critical need for more sustainable alternatives. In response, this study explores a novel approach utilizing a cross-linked gel matrix derived from Jin Shofu starch, chemically and physically modified, and combined with citric acid, a natural chelating and cleaning agent. The cross-linking process is achieved using sodium trimetaphosphate and sodium tripolyphosphate, which are common in the food industry for modifying starch properties. In addition, the freeze-thaw technique exploits the formation and melting of ice crystals to alter the molecular structure of starch, creating new hydrogen bonds and reinforcing the starch matrix's internal cohesion. This method eliminates the need for additional chemical agents, further advancing the sustainability of the process. The starch-based gel's biodegradability and compostability ensure that any waste generated during the cleaning process can be disposed of in an environmentally friendly manner, reducing the overall impact of conservation practices.