Thesis title: Terpene-based cleaning systems in art conservation
This research investigates the development of sustainable, bio-inspired cleaning systems for cultural heritage, specifically targeting the removal of acryl and alkyd overpaints from various substrate. Grounded in the principles of "Green Conservation," the study evaluates essential oils and their primary terpene constituents, notably linalool (from Lavandula hybrida) and 1,8-cineole (from Laurus nobilis), as bio-available alternatives to hazardous petrochemical solvents. The methodology integrates the chemical characterisation of essential oils via GC-MS with Hansen Solubility Parameters (HSP) to theoretically predict solvent-polymer interactions. Crucially, the research expands beyond thermodynamic affinity by investigating the empirical diffusion kinetics and swelling dynamics of whole phytocomplexes compared to their isolated primary components. To achieve operational control, the study presents two primary soft-matter delivery systems tailored for distinct cleaning challenges. A linalool-based oil-in-water (O/W) microemulsion was developed for the removal of alkyd-based spray paints from porous matrices, such as cement and mortar. Experimental results, supported by Small-Angle X-ray Scattering (SAXS), confirm that this system operates via a dewetting mechanism, enabling the detachment of the synthetic film without compromising the original substrate. Moreover, to address the high sensitivity of classical gilded decorations, terpene-based solvents were confined within chemical organogels. This structural confinement provided the necessary control to selectively remove non-original overpaints whilst preserving the fragile underlying gold leaf and preparation layers. Finally, the environmental viability of these systems was assessed through a screening Life Cycle Assessment (LCA) and green chemistry metrics, highlighting specific parameters to reduce the ecological footprint of custom-distilled natural Eos. By bridging the gap between advanced physical chemistry and environmental responsibility, this research provides a scientifically validated toolkit for the conservation of both modern urban art and classical decorated surfaces.