Investigations of paint coatings in the context of cultural heritage science present a unique set of technical challenges because of the evolution of the properties of materials over time scales that are much too long to be reproduced directly. As a result, data-driven kinetic models of the aging process are needed in order to understand the physical state of aged paints and to develop effective restoration and cleaning strategies. In this collaborative project involving Northwestern University and the Art Institute of Chicago, a kinetic Monte Carlo model of paint curing and aging will be developed, as will experimental systems needed to determine relevant model parameters. The net result will be a set of simulation models that can be viewed as 'virtual' oil-based paint coatings. These 'virtual' coatings will enable the time dependent, structural features of complex, multicomponent paint coatings to be tracked. The models, with their experimentally determined input parameters, represent a physical and chemical knowledge base for oil-based paint coatings that will serve as a platform for addressing a wide range of questions. Specific issues to be addressed concern the curing and aging of systems when subjected to heat, humidity and various cleaning solutions. Kinetic parameters will be determined experimentally with coatings made from well characterized starting materials, using the quartz crystal microbalance (QCM) as the primary experimental tool. Nanoindentation will be used to correlate the high frequency mechanical response obtained with the QCM to complementary measures of the mechanical response and to actual paint samples. While these techniques will be applied directly to oil-based coatings used by artists, the methodology is broadly applicable in a variety of areas, including characterization of high performance protective coatings, and the development of sustainable, bio-derived materials.
NON-TECHNICAL SUMMARY:
This project is a collaborative effort between Northwestern University and the Art Institute of Chicago. State-of-the art scientific tools will be used to study the curing and aging properties of modern oil-based paints and the impact of conservation treatments on them. Although oil-based paints were widely used throughout the 20th century, and in some of the most prominent artworks of that period, their properties are poorly understood. Advancing our knowledge in this area is crucial for preserving the integrity of such artworks for future generations. The results of this research will be used to develop more effective conservation strategies for paintings in collections at the Art Institute and at other museums throughout the world. An educational outreach element linking science and art will also be developed in conjunction with the Art Institute's Department of Museum Education. Outreach offerings will be developed to attract middle school and high school science classes to the museum. These activities will be designed to attract students to science who would otherwise not likely be drawn to science-related programs. Similarly, the connection with the Art Institute will enable undergraduate and graduate students at Northwestern to understand the ways in which scientific concepts can benefit disciplines that lie outside the traditional scientific realm.
