Assessing the swelling behavior of oil paint in fatty acid methyl esters (FAMEs)

Fatty Acid Methyl Esters (FAMEs) have gained attention as low-impact solvents, offering low toxicity and versatility in applications ranging from biofuels to chemical feedstocks. This study investigates the swelling behavior of naturally-aged zinc white oil paint fragments when exposed to FAMEs with varying chain lengths. Swelling was monitored using a microscopy-based image analysis technique over a 15 minutes period, demonstrating that FAMEs induce low to moderate swelling in oil paints, consistent with prior findings on solvent-paint interactions. The degree of swelling is influenced by the molecular properties of the solvents, such as polarity, chain length, and rate of diffusion. Additionally, the study underscores the importance of considering the competing processes of swelling and leaching, where solvent penetration can lead to the extraction of low-molecular-weight components from the paint matrix. This research underscores the need for careful solvent selection in conservation practices to minimize the risk of swelling-induced damage and leaching. Further studies are required to fully understand the long-term effects of FAMEs on oil paint stability and integrity.