Liaisons Dangereuses, Conservation of Modern and Contemporary Art: A study of the synthetic binding media in Portugal
Joana Lia Ferreira
Department of Conservation and Restoration and Requimte – FCT/Universidade Nova de Lisboa
Maria João Melo; Ana Maria Ramos, María Jesús Ávila
Date of completion
January 31st 2011
Poly(vinyl acetate) - PVAc; vinyl emulsions; poly(methyl methacrylate) - PMMA; acrylic sheet; photodegradation; Joaquim Rodrigo; Ângelo de Sousa; Lourdes Castro
This project was focused on the study of synthetic materials used by Portuguese artists in the twentieth century. The main purpose of the study was the molecular characterization of vinyl polymers used in waterborne emulsion paints since the 1950s and the study of their evolution over time. The molecular photodegradation of PVAc was studied; the presence of degradation products on references, model samples and dated works of art was investigated. The artists Joaquim Rodrigo (1912-1997) and Ângelo de Sousa (b.1938) were chosen as case studies. Accelerated photodegradtion studies were performed and the results achieved by means of infrared micro-spectroscopy point out the considerably stable nature of these binding media. The photodegradation process was further studied by means of size exclusion chromatography following the molecular weight distribution. It was concluded that main-chain scission is the major degradation mechanism, although not yet affecting the polymer performance. The influence of pigments on the polymer’s stability was also considered. Photodegradation quantum yields were calculated for monochromatic irradiation at 313nm and the polymer was determined to be very stable; therefore, degradation is quantified and a comparison may be performed for different polymers.
A parallel study, according to a similar experimental approach, was undertaken on the stability of poly(methyl methacrylate) – PMMA. Dated samples belonging to Lourdes Castro were studied.
How to access the dissertation
Available online: http://hdl.handle.net/10362/5342
Previous education and/or work experience
2003-2010 Teaching experience (History of art technology and materials, Polymers in conservation, Project co-supervising); 1999-2004 Field work as a private conservator; 2003 Graduate degree in Conservation and Restoration (research project on the characterization of vinyl paints); 2001 Bachelor in Conservation and Restoration (internship focusing on the conservation of a contemporary wall painting).
Collaborator at the Department of Conservation and Restoration – FCT/Universidade Nova de Lisboa
Joana Lia Ferreira
Address: Dept. de Conservação e Restauro – FCT/UNL, Campus da Caparica, Quinta da Torre, 2829-516 Caparica, Portugal
Phone: +351 212948322 / +351 962904621
URL: http://www.dcr.fct.unl.pt/ / http://www.cqfb.fct.unl.pt/fotoquimica/