Acrylonitrile-butadiene-styrene (ABS) is a well-known discard product from the industry. This copolymer can be dissolved in organic solvents, and thin films can be created by immersion. Two requirements for coatings used for cultural heritage conservation purposes are transparency and reversibility, both fulfilled by ABS films. The aim of this work was to characterize the copolymer and to evaluate the electrochemical properties of ABS coatings applied to copper. Such performance was compared to that of a commercial varnish commonly used in conservation. The results indicate high protection values of the ABS film, generating a potential application for this waste material. The electrochemical techniques included electrochemical noise, impedance spectroscopy, and potentiodynamic polarization. 1. Introduction Cultural heritage conservation constitutes a relevant field of research which frequently relies on material science to solve the challenges posed by the degradation of artifacts, architectural structures, and ornaments [1–5]. Historic, artistic, and archaeological items are frequently built of metals. Through the ages, copper and its alloys constitute a particular set of metals widely used in such manufactures [6]. Even when these materials tend to form protective patinas due to their interactions with the environment, such natural protective layers may fail, especially in highly polluted atmospheres [7]. Therefore, the application of coatings to both clean and patina covered metallic surfaces has proved to be useful to preserve cultural heritage [8]. Two highly desirable conditions of conservation-oriented coatings are transparency in order not to affect the aesthetical traits of the artifacts and reversibility, which refers to an easy removal process [9]. On the other hand, acrylonitrile-butadiene-styrene (ABS) waste and residues represent a well-known discard product from the automotive industry. Since law usually forbids the recycling of this material because all pieces must be brand new, considerable amounts of ABS become unused waste and a nuisance to dispose due to environmental restrictions. Therefore, research has been done trying to find usable recycling applications with added value to this and other polymer discards. Due to the finite reserve of hydrocarbon in the world, a proposal has been obtaining degradation oils from plastics, potentially useful as fuel [10]. However, such processes cannot avoid the presence of heteroatoms such as chlorine from poly(vinyl chloride) (PVC) or nitrogen from ABS. These heteroatoms relate to corrosion of
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