Synthetic and semisynthetic polymer materials are dominating the materials within many of the contemporary and modern collections of galleries and museums. For over a century now, they enable the creation of new and exciting forms of art and design expression and tell a story about 20th- and 21st-century civilisation. The conservation of this heritage is necessary, but conservators and scientists still don't have clear guidelines for reaching this goal.
Conservatory prevention is a branch of conservation sciences, which works on modifying the storage conditions of artworks to enable simultaneous care for multiple objects at once in the most economically and ecologically effective way and at the same time allow for wide access to those objects. The accomplishment of the goal requires an understanding of the basic mechanism of the material's degradation - that requires in-depth research - and an evaluation of the ongoing research in terms of the supervision and management of collections. The previous findings have shown that of the most popular plastic materials within art collections, three are most prone to accelerated ageing because they undergo a degradation that can be visible even within a few decades of the creation of the art piece, which leads to the diminishing of esthetical value, an increase in viscosity and development of craquelure (a network of cracks and fractures) - collectively, to the disturbance of the art reception. Finally, chemical and mechanical degradation of cultural heritage objects can lead to their loss. The three most endangered polymers are cellulose acetate and nitrate, and poly(vinyl chloride), PVC. The first two have already been exhaustedly researched, while PVC, which can comprise even up to 13% of nowadays art collections, hasn't been yet the subject of common, domestic or international research efforts.
To fill this gap in science, a team of researchers from the Faculty of Chemistry at the Jagiellonian University, the Jerzy Haber Institute of Catalysis and Surface Chemistry of the Polish Academy of Sciences and the University of Ljubljana, with many years of joint experience in the field of polymer and heritage sciences, have combined their efforts with conservators and curators from Centre for the Documentation of the Art of Tadeusz Kantor Cricoteka, Kraków, Museum of Architecture and Design, Ljubljana, and Centre Pompidou, Paris. The collaboration of scientists from Poland and Slovenia is an additional asset of this project by being uniquely beneficial for its execution because the combined efforts of both countries will enable effective work on this complex subject. In addition, the collaboration will allow for the combination of available resources, which will make the research much more efficient and holistic, not confined to the chemical point of view.
The main goal of the research is an in-depth analysis of the degradation processes of PVC within art collections, and the determination of the mechanisms of chemical and mechanical degradation in historical samples by using many different techniques and computer models of the damage accumulated in samples. The damage means especially the processes that occur during conservatory handling of pieces throughout extended periods of time, e.g. discolourations, changes in the viscosity of the surface or the development of craquelure. On the basis of understanding and connections modelling between the rate of degradation, environmental factors and the material composition, it will be possible to prepare extensive conservatory guidelines for PVC pieces.
Even though poly(vinyl chloride) and the plastic material made out of it were undergoing extensive studies by scientists and engineers, the subject of the research was mainly the degradation that is taking place at highly elevated temperatures or under UV irradiation, and such studies have limited use for the conservatorship protections of art. So, it is necessary to run further research to understand the mechanism of the degradation of PVC during its storage, under museum conditions, which are close to room temperature.
Additionally, the outcome of this multifaceted research on the degradation of PVC will be the development of an innovative tool for online modelling, which will enable conservators to analyze their storage conditions and create attuned environmental guidelines for their collections. This will greatly expedite the implementation of necessary strategies for possibly the most effective reduction in the rate of ageing of PVC heritage pieces.