Yvonne Shashoua

Development of a conservation strategy for a collection of waterproofed military uniforms

Abstract The development of a conservation strategy to prolong the useful lifetime of a collection of waterproofed military uniforms dating from 1880 to 1960 is described. Waterproofing agents present at the surfaces of each costume were identified, mainly using Attenuated Total Reflection‐Fourier Transform Infrared spectroscopy, as: drying oils from plant and fish sources, bitumen, natural rubber and plasticised polyvinyl chloride (PVC). Despite the fact that most uniforms had never been worn, many exhibited extensive deterioration: oil‐treated uniforms were tacky due to incomplete oxidation either because of incomplete preparation of the oils or excessively thick application. Bitumen‐waterproofing was tacky because it had depolymerised during exposure to light. By changing the storage environment to one of stable moderate temperature and relative humidity, it is suggested that the deterioration of the waterproofing materials would be slowed to some extent. Uniforms treated with oils or bitumen also require external covers to isolate their tacky surfaces, and internal support to maintain their shape. Tests suggested that uniforms treated with oils could be supported by silicone paper or polyethylene‐based films; suitable covering materials were polyethylene and Cryovac® BDF‐200. Uniforms treated with bitumen could be supported by polyethylene film and covered by polyethylene, Melinex® or Cryovac BDF‐200. Natural rubber‐treated uniforms had oxidised, developing cracks and crazes: oxygen‐free storage is recommended. Uniforms waterproofed with plasticised PVC exhibited slight tackiness due to migration of plasticiser.

Mesocycles in conserving plastics

Analysis suggests that progress in conservation of plastics objects and artworks can be described by a series of overlapping mesocycles. Focus has been placed for periods of 5–10 years each on determining the degradation pathways in the 1990s, developing strategies to inhibit those pathways from the late 1990s and, since 2006 on actively stabilizing and treating the symptoms of degradation. The primary driving forces behind the direction and rate of progress within each of these three mesocycles have been different and specific. The controlling factor in understanding degradation pathways for heritage plastics has been the origin of the data describing lifetimes. By contrast, mesocycles in developing suitable storage and display microclimates for plastics have mirrored preventive conservation practices for natural polymeric materials. The rate of the third mesocycle, interventive conservation, has been driven by the need to balance the requirements for reversibility in conservation practices with the artists intent and significance. Developments within each of the three mesocycles from the 1990s to date are discussed in this article. Environmental science and toxicology of waste plastics offer a novel source of information about real time degradation in terrestrial and marine microenvironments that seems likely to contribute to the conservation of similar materials in contemporary artworks.

Poliflexsol polyester resin: It's properties and applications to conservation

Abstract Poliflexsol is a light curable, glass fibre reinforced polyester resin supplied in sheet form. Since sheets of Poliflexsol are contained between two nylon films, the resin is clean and easy to handle. Its high flexibility allows it to be shaped as required and this has led to its application as a support material. The purpose of this paper is to present the results of an investigation into the properties of Poliflexsol and to describe three examples of its use both on and off‐site. Poliflexsol undergoes minimal shrinkage on curing and ageing and is suitable for use with metals and organic materials.