Colloidal Properties of Aqueous Poly(vinyl acetate)–Borate Dispersions with Short‐Chain Glycol Ethers

Abstract

We report the influence of adding five short-chain glycol ethers (SCGEs) on the structure, stability, and viscoelastic properties of aqueous dispersions of partially hydrolyzed poly(vinyl acetate) and borax. The properties of these gel-like materials have been investigated as a function of the structure of the added SCGE both below and above the critical aggregation (or micellar) concentrations using (11) B and (13) C NMR, rheology, and small-angle neutron scattering. The results indicate that the SCGE aggregation behavior is not affected by incorporation into the gel-like network. However, changes in the viscoelasticity and structural properties of the dispersions were detected that can be correlated to the nature of the solvent system. Also, the ability of these materials to clean an unvarnished acrylic paint surface coated with synthetic soil has been evaluated using colorimetery, and the surface of the dispersion after cleaning was visualized with scanning electron microscopy.

Maximizing Contact of Supersoft Bottlebrush Networks with Rough Surfaces To Promote Particulate Removal

“…Typically, gels are used to deliver a cleaning liquid to the topmost layer of the art surface. However, recent studies have demonstrated that gels can be used to gently remove particulate contaminants by pressing and peeling from the surface. ,, For a gel to be effective in removing particulates from a surface, it should be able to (1) conform to the topography of the rough surface (to increase the surface area capable of being cleaned), (2) conform around individual particulates (as an increase in contact area will increase the adhesive force between the two materials), and (3) provide favorable surface energetics at the interface to promote chemical adhesion.…”

“…In the context of conservation of works of art, soft materials (i.e., gels) have been used in a variety of applications, including material (e.g., pigment) identification, − solvent delivery to aid in the removal of stains or deteriorated layers, − or removal of particulate contaminants. − One common feature in all of these applications is the requirement for a gel to make intimate contact with a substrate surface. Although the removal of contaminants from delicate surfaces can be achieved with dry (e.g., laser ablation, , microfiber cloths, and polymeric micropillars) and wet (e.g., solvents, surfactants, and microemulsions) methods, gels have been shown to be a gentle and effective strategy. ,, However, the contact between soft cleaning materials (e.g., gels) and substrates has not been investigated in relation to cleaning efficacy.…”

Soft, Peelable Organogels from Partially Hydrolyzed Poly(vinyl acetate) and Benzene-1,4-diboronic Acid: Applications to Clean Works of Art

“…In a third example, it was found that the x PVAc/borax gel-like materials (i.e., containing added water) ,,, were more efficient than the dry x PVAc/BDBA ones at removing an oil-based layer. During treatment, a conservator found that a nonoriginal drying oil layer on Portrait of an Old Woman by Maarten de Vos (1556) (Figure S9) could not be removed with solvents.…”

“…Although swab cleaning removed only a small portion of the swelled layer (Figure 10j), it was removed effectively with a bamboo skewer to lift the softened varnish from the underlying paint surface (Figure 10k) and brushing the pieces away (Figure 10l) to reveal the paint layer below (Figure 10m). In a third example, it was found that the xPVAc/borax gellike materials (i.e., containing added water) 18,30,34,35 were more efficient than the dry xPVAc/BDBA ones at removing an oilbased layer. During treatment, a conservator found that a nonoriginal drying oil layer on Portrait of an Old Woman by Maarten de Vos (1556) (Figure S9) could not be removed with solvents.…”