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

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 amethacrylic/acrylic copolymer (Paraloid B72) film laid on glass surfaces and several NSFs,b ased on two solvents and two surfactants.The experimental results provide adetailed 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 anonionic 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.Aged and discolored varnishes,old fixatives,a dhesives,a nd

Twin-Chain Polymer Networks Loaded With Nanostructured Fluids for the Selective Removal of a Non-Original Varnish From the Picasso’s “L’atelier” at the Peggy Guggenheim Collection, Venice

“…Moreover, a system composed by mixed micelles of nonionic/ionic surfactants in the presence of two water-miscible solvents, which are partitioned between the aqueous and the micellar phase, is structurally more complex than classically-defined o/w microemulsions composed of water/oil/surfactant and whose PDI usually does not exceed 0.2-0.4 [47,48]. The shell thickness is quite high, as usually is for systems based on alcohol ethoxylates with medium/long polar head chains, but in agreement with the data obtained on previous systems based on the same or similar surfactants [18,19,49,50]. Finally, the SLD of the continuous phase is consistent with the almost complete solubilization of both BuOH and MEK in the ethoxylates groups/water, with little penetration of organic solvents in the micelles' hydrophobic core.…”

Twin-chain polymer hydrogels based on poly(vinyl alcohol) as new advanced tool for the cleaning of modern and contemporary art

“…In past years, we have developed a different approach based on the use of colloidal systems (10)(11)(12)(13)(14)(15)(16)(17). The latest advancement is represented by the confinement of cleaning fluids in gels (18)(19)(20) specifically tailored to treat water-and solvent-sensitive works of art.…”

Graphene‐Enhanced Nanomaterials for Wall Painting Protection

“…Wall paintings are the commonwealth of human beings and highly valuable to learn more about our ancestors . However, wall paintings have been facing severe damaging problems over the years, including color change due to ultraviolet (UV) irradiation (Figure S1a,b, Supporting Information), flaking phenomena (Figure S1c,d, Supporting Information) because of crystallization and dissolution of salt, hollowing (Figure S1e, Supporting Information), fungus damage, and cracks. The fact is that wall paintings are quite fragile compared with other cultural relics such as ancient metals, jades, and pottery, and it is hard to protect them compared with cultural heritage artifacts as mentioned above (Figure S2, Supporting Information) .…”

“…The fact is that wall paintings are quite fragile compared with other cultural relics such as ancient metals, jades, and pottery, and it is hard to protect them compared with cultural heritage artifacts as mentioned above (Figure S2, Supporting Information) . So far, various organic materials such as Paraloid B72 and Primal AC33 have been developed for the protection of wall paintings due to the easy permeation into wall painting, good adhesion, and excellent transparency . However, low compatibility, quick degradation, and color change with time cause severe cracking, flaking, and even detachment of the pigments from painting's surface, making them unsuitable as conservation materials .…”