Speaker
Descrizione
Metallic artworks are highly susceptible to rapid deterioration driven by complex chemical and electrochemical reactions. These processes are triggered by several environmental factors, including temperature, humidity, oxygen and concentration of airborne corrosive species. Materials design can significantly contribute to the preservation of metallic cultural heritage by enabling the development of advanced protective coatings capable of isolating artifacts from external aggressive agents. However, coatings intended for precious artistic and historical objects must meet stringent requirements: they must be highly transparent and preserve the original appearance of the surface; they must be easy and safe to apply and remove; they must provide effective barrier properties against corrosive species, and retain all these properties over a long service life.
In this contribution, we present our ongoing efforts conducted within the EU GREENART project in the design, development and validation of sustainable protective coatings based on biopolymers derived from natural and/or waste resources and containing green functional additives such as corrosion inhibitors and nanofillers [1,2]. We aim to highlight the main challenges and open research questions associated with the development of sustainable conservation materials for metallic heritage. Our ultimate goal is to further improve our current coating technologies, which already demonstrate a high level of technological readiness, by enhancing their effectiveness through the introduction of additional functionalities.
In particular, we address the intrinsic hydrophilicity of many biopolymer-based coatings, which limits their barrier performance in highly humid environments. Strategies such as the incorporation of nanofillers to enhance hydrophobicity are promising, but still require systematic investigation to balance effectiveness with transparency and reversibility. The second challenge concerns the long-term chemo-physical stability of biopolymer coatings. Mitigating degradation induced by light exposure or radical processes remains an open issue, particularly when strict aesthetic requirements must be fulfilled.
Furthermore, a significant open question concerns the in-depth understanding of the complex interactions between corrosion inhibitors and metal surfaces, which can seriously compromise their efficacy if not properly assessed. The performance of inhibitors is strongly influenced by the geometry and chemistry of their adsorption, which vary depending on the metal type, surface condition, and oxidation state (e.g., cleaned or patinated surfaces). A deeper insight into these interfacial mechanisms is essential to ensure reliable protective performance.
Finally, we propose to broaden the applicability of these biopolymer-based systems beyond metallic substrates to encompass other classes of materials. This perspective opens new opportunities, but also raises additional questions regarding compatibility, durability, and functional performance across different contexts.
[1] Boccaccini F., Giuliani C., et al. Toward a Green and Sustainable Silver Conservation: Development and Validation of Chitosan-Based Protective Coatings. International Journal of Molecular Sciences. 2022; 23(22):14454. 10.3390/ijms232214454
[2] Boccaccini F., Pascucci M., et al. Sustainable biopolymers as protective coatings against indoor corrosion of bronze: A comparison among alginate, carboxymethyl cellulose, chitosan and pectin. International Journal of Biological Macromolecules. 2026; in press. 10.1016/j.ijbiomac.2026.153088
| Giovane Ricercatore (under 40) | Yes |
|---|
