Tough and translucent hydrogel electrode for electrochemical cleaning of paper artworks

Abstract

Due to the favorable retention power and viscosity, the hydrogel that is loaded with an aqueous detergent, represents a promising cleaning tool for removing the foreign matters such as polymer adhesive, starch paste, and animal glue from paper artworks. However, it is still challenging to eliminate other stains, including organic dyes, commercial drinks, foxing, and mildew. Herein, we present an alternative methodology, translucent hydrogel-containing electrolyte-based electrochemical cleaning (EC), which incorporates electrochemical reactions into the hydrogel-based cleaning process using the extremely tough and translucent alginate/polyacrylamide hydrogel as cathode and PbO2 as anode. The proposed approach is generally applicable to eliminate different stains such as organic dyes, commercial drinks, mildew, and foxing from paper under several mA/cm2 and a few minutes in a small controlled area. For the excellent mechanical strength, the hydrogel electrode can be reused for several times without losing its efficiency and easily peeled-off from paper as one body without any gel residues after cleaning. We further demonstrate the effect of EC on the treated paper, including the morphology, degree of polymerization, crystal structure, and mechanical properties. We conclude that the influence of EC on the paper is slight under the mild treatment.