Applying Atmospheric Chemistry to Art Conservation in the Laboratory and the Classroom

Abstract

There are millions of art and cultural heritage objects displayed and stored across Canada, which have historical, cultural, and aesthetic importance to the Canadian people and the world. Cultural heritage is chemically complex and reactive with its environment; its conservation over decades and centuries has necessitated research in materials science and environmental chemistry. In the course of better understanding how cultural heritage degrades, conservation scientists have identified gaps of fundamental chemical knowledge in their research projects that may be challenging to answer in conservation laboratories, but that atmospheric and analytical chemists are equipped to address. In this thesis, I aimed to apply analytical and atmospheric chemistry techniques to further understanding of conservation science research questions and foster increased collaboration between these two fields. In the first project, I apply art conservation science as a context for chemistry education in the development of “Chemistry in the Art Gallery,” a week-long module teaching environmental chemistry to non-chemistry undergraduate students. In addition to providing students a holistic overview of conservation research, this module gave students hands-on opportunities to study museum-relevant reactions and helped them foster a connection with a local museum by examining art from both aesthetic and chemical perspectives. In the second project, I model the morphology dependence of titanium dioxide-catalyzed photodegradation of acrylic paint surfactants. This photodegradation has been identified on mid-century acrylic artworks and is an area of concern and further study for acrylic conservation scientists. Here, I show that this reaction proceeds rapidly in the presence of anatase, but is slower in rutile and coated pigments, which suggests that art objects with anatase are more susceptible to this reaction. I also investigate the wavelength dependence of the photodegradation to further assess conditions under which it may be suppressed. In the third project, I characterize the effect of material suitability test parameters on emission profiles from museum-relevant construction materials. These are used to construct enclosures to house cultural heritage objects, and conservation scientists artificially age them at elevated conditions to determine if the volatile species they emit pose risk to heritage materials. In this work, I show that museum-relevant species are affected by changes to temperature and humidity, and that the high heat, high humidity environments of the artificial aging test may lead to under-sampling of relevant water-soluble pollutants. I also show how sample age, material manufacturer, and sample preparation can affect the emission profiles obtained. Conservation science is a complex, multifaceted field of research, and analytical and atmospheric chemists can make meaningful contributions to this field’s research through collaboration with conservation scientists. This thesis provides key insights into chemical processes relevant to understanding and preventing heritage degradation, which will enable conservation scientists to develop better methods to preserve art and cultural heritage.