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

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.