Environment-Friendly Poly(2-ethyl-2-oxazoline) as an Innovative Consolidant for Ancient Wall Paintings

Abstract

The research of innovative materials on the conservation of ancient wall paintings has given rise to increased attention in recent years. One of the most used synthetic organic consolidation material for the wall paintings is the commercial acrylic resin Paraloid B72 (PB 72), which encounters problems of the use of toxic solvents, low water vapor transmission, and poor penetration. Here, the non-toxic, environment-friendly product poly(2-ethyl-2-oxazoline) (PEOX) has been demonstrated as a great potential consolidant for wall paintings to solve these issues. First of all, thanks to the better penetration ability, the simulating plaster sample treated with PEOX shows greater enhanced surface hardness than PB 72. The single-lap joint shear strength test and the scotch tape test revealed the good adhesion of PEOX on inorganic surfaces and effective pigment consolidation. At the same time, the PEOX-treated sample presents less surface gloss. The hydrophilic nature of PEOX merits itself with superior water vapor permeability compared with PB 72. These advantages enable PEOX to be a progressive choice to replace the use of PB 72 in the controlled indoor working environment.

Mechanical enhancement of cellulose nanofibril (CNF) films through the addition of water-soluble polymers

“…Likewise, PEOX is a low cytotoxicity polymer with good light stability and re-solubility. The PEOX structure contains a substituted amide group (Fig SI3 (b), that polymerizes by cationic ring-opening polymerization (Zhang et al 2018). PEOX is suspected to form hydrogen-bonded complexes with polymers containing proton donating groups (Lin et al 1988).…”

Bone-adhesive barrier membranes based on alendronate-functionalized poly(2-oxazoline)s

“…We attributed the higher work of adhesion values of P(EtOx)-impregnated membranes than with other POx groups to the hydrophilic nature of P(EtOx). 46 Importantly, all POx-impregnated membranes showed similar shear strength and work of adhesion values. Nevertheless, the standard deviations are large which compromise the statistical analysis.…”

Water vapor transmission properties of acrylic organic coatings

“…For example, we only found two works of which data could be used to estimate these quantities for the Paraloid B72. Carretti et al 11 and Zhang et al 23 measured the WVTR of plaster and mortar samples coated with Paraloid B72. Their aim was to show that the new coating materials they studied had much higher WVTR than that of the Paraloid B72, which is favorable to protect wall paintings.…”

“…To examine if the results obtained for the coatings prepared by the spin coating can be applied in general, we also used brushing as it is the most frequently used technique in art conservation. 23 In this case, we dropped 0.6 ml on the substrate surface with an automatic pipette, and the whole surface of the substrate was covered by using a soft brush. The thicknesses of the coating layers were 10 lm (± 20%).…”

“…One of the most important physical properties of the coatings is the water vapor transmission rate (WVTR). 5,11,[19][20][21][22][23][24] In some cases, low WVTR, and in other cases, high WVTR is desired. For example, in the case of wall paintings, the water inside them exchanges with the outer environment in the form of vapor through the porous structure.…”