Polymer Film Dewetting by Water/Surfactant/Good-Solvent Mixtures: A Mechanistic Insight and Its Implications for the Conservation of Cultural Heritage

Michele Baglioni; Costanza Montis; David Chelazzi; Rodorico Giorgi; Debora Berti; Piero Baglioni

doi:10.1002/anie.201710930

Polymer Film Dewetting by Water/Surfactant/Good-Solvent Mixtures: A Mechanistic Insight and Its Implications for the Conservation of Cultural Heritage

Angew Chem Int Ed Engl. 2018 Jun 18;57(25):7355-7359. doi: 10.1002/anie.201710930. Epub 2018 Jan 11.

Authors

Michele Baglioni¹, Costanza Montis¹, David Chelazzi¹, Rodorico Giorgi¹, Debora Berti¹, Piero Baglioni¹

Affiliation

¹ Department of Chemistry and CSGI, University of Florence, via della Lastruccia 3, 50019, Florence, Italy.

PMID: 29215783
DOI: 10.1002/anie.201710930

Abstract

Aqueous nanostructured fluids (NSFs) have been proposed to remove polymer coatings from the surface of works of art; this process usually involves film dewetting. The NSF cleaning mechanism was studied using several techniques that were employed to obtain mechanistic insight on the interaction of a methacrylic/acrylic copolymer (Paraloid B72) film laid on glass surfaces and several NSFs, based on two solvents and two surfactants. The experimental results provide a detailed picture of the dewetting process. The gyration radius and the reduction of the T_g of Paraloid B72 fully swollen in the two solvents is larger for propylene carbonate than for methyl ethyl ketone, suggesting higher mobility of polymer chains for the former, while a nonionic alcohol ethoxylate surfactant was more effective than sodium dodecylsulfate in favoring the dewetting process. FTIR 2D imaging showed that the dewetting patterns observed on model samples are also present on polymer-coated mortar tiles when exposed to NSFs.

Keywords: art conservation; cleaning; dewetting; micelles; microemulsions.

Publication types

Research Support, Non-U.S. Gov't