Dewetting acrylic polymer films with water/propylene carbonate/surfactant mixtures – Implications for cultural heritage conservation
Authors: Baglioni M., Montis C., Brandi F., Guaragnone T., Meazzini I., Baglioni P., Berti D.
Autors Affiliation: Chemistry Department, CSGI, University of Florence, via della Lastruccia 3, Sesto Fiorentino, FI 50019, Italy; School of Chemistry, Trinity College, University of Dublin, College Green, Dublin 2, Ireland
Abstract: The removal of hydrophobic polymer films from surfaces is one of the top priorities of modern conservation science. Nanostructured fluids containing water, good solvents for polymers, either immiscible or partially miscible with water, and surfactants have been used in the last decade to achieve controlled removal. The dewetting of the polymer film is often an essential step to achieve efficient removal; however, the role of the surfactant throughout the process is yet to be fully understood. We report on the dewetting of a methacrylate/acrylate copolymer film induced by a ternary mixture of water, propylene carbonate (PC) and C9-11E6, a nonionic alcohol ethoxylate surfactant. The fluid microstructure was characterised through small angle X-ray scattering and the interactions between the film and water, water/PC and water/PC/C9-11E6, were monitored through confocal laser-scanning microscopy (CLSM) and analised both from a thermodynamic and a kinetic point of view. The presence of a surfactant is a prerequisite to induce dewetting of µm-thick films at room temperature, but it is not a thermodynamic driver. The amphiphile lowers the interfacial energy between the phases and favors the loss of adhesion of the polymer on glass, decreasing, in turn, the activation energy barrier, which can be overcome by the thermal fluctuations of polymer film stability, initiating the dewetting process.
Journal/Review: PHYSICAL CHEMISTRY CHEMICAL PHYSICS (PRINT)
Volume: 19 (35) Pages from: 23723 to: 23732
More Information: Cordis, H2020-NMP-21-2014/646063. European Geosciences Union, EGU. Yukawa Institute for Theoretical Physics, Kyoto University, YITP. – Orlando Cialli is acknowledged for the assistance during some experiments. CSGI is acknowledged for partial funding of this work, otherwise supported by the European Union (CORDIS) – Project NANORESTART (H2020-NMP-21-2014/646063). Marcell Wolf is gratefully acknowledged for assistance with the SAXS experiments at the Austrian beamline (Elettra, Trieste, Italy). IM gratefully acknowledges the support of a Young Investigators Training Program (YITP) scholarship financed by ACRI (Italian Banking Foundation Association).KeyWords: Conservation; Ethyl silicate; NONIONIC SURFACTANTS; MICELLAR-SOLUTIONSDOI: 10.1039/c7cp02608kCitations: 10data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2019-09-15References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here