Abstract
This research evaluates the stability of an aqueous emulsion of acrylic copolymers and waxes. Edelwachs, generally applied on wood, has been recently used as an unconventional medium in contemporary painting. Through Pyrolysis–Gas Chromatography–Mass Spectrometry (Py-GC-MS) and Fourier Transformed Infrared Attenuated Total Reflectance (FT-IR-ATR) analyses, the composition of Edelwachs was defined as a mixture of acrylic polymers (MA, MMA, nBA, nBMA), Carnauba and microcrystalline waxes and additives. Mock-ups-obtained mixing Edelwachs with titanium white, zinc white and ultramarine blue were subjected to UV, high temperatures, and high relative humidity accelerated ageing. The effect of the ageing procedures was evaluated through optical microscopy, colourimetric measurements, FT-IR-ATR, Thermogravimetry and Differential Scanning Calorimetry (TG-DSC) and wettability measures. FT-IR-ATR spectra do not show significant variations in terms of chemical stability, indicating a fair stability of Edelwachs as a painting binder. UV and high temperature treatments show the most relevant effects in terms of colorimetric changes (increasing of b*) and thermal stability. The TG-DSC highlights the influence of the pigments (specifically zinc white) mainly on the thermal behaviour of the acrylates. The unexpected decrease of wettability of the paint films, registered after ageing, may indicate a possible phase separation among acrylates and waxes.
Highlights
In the last decades, the scientific literature has been enriching in research related to the study and the stability of polymeric films in the field of Heritage and Conservation Science for contemporary art
This study takes into consideration an anomalous pictorial binder used in contemporary art, never studied either from a compositional point of view or regarding its stability over time; this product, named Edelwachs, is commercially sold as a wood coating produced by Pigrol (Tikkurila GmbH, Germany)
The main aim of this paper was to study the stability and the durability of paint films obtained with Edelwachs and mixed with three different inorganic pigments, namely ultramarine blue, titanium and zinc white
Summary
The scientific literature has been enriching in research related to the study and the stability of polymeric films in the field of Heritage and Conservation Science for contemporary art. This topic represents a relevant and current focus, in consideration of the relative instability, sometimes unexpected, found in numerous artworks. The assessment of the ageing and durability of these polymers is, fundamental for studying and understanding their behaviour over time and for preserving artworks in which they have been (sometimes unconventionally) employed as binding media and coatings or finishing layers. According to the technical sheet, it consists of a complex mixture containing wax emulsion, acrylic dispersion, additives, organic and mineral pigments and water.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
