Evaluation of cold flow of structural adhesive joints for sculpture conservation

Erik Risser and Jerry Podany


Expanding on earlier work between the Department of Antiquities Conservation at the Getty Museum in Los Angeles and the Conservation Department of the Nelson Atkins Museum in Kansas City on the properties of Paraloid B-72, the current studies are an initial evaluation of the long-term creep and cold flow deformation of adhesive/solvent mixture layers used in the assembly of large scale structural joints in sculpture. Paraloid B-72 mixed with a variety of solvents and in a variety of percentages was tested both as an adhesive and as a reversible barrier coating coupled with structural two-part epoxy resin between marble test joints. Test joints were prepared to mimic mid-size structural joints between segments of marble sculpture (i.e. slightly over-life-size, outstretched arm segment attached at the shoulder) and were placed under equal constant cantilevered load mimicking realistic forces within reassembled sculpture. The joints were monitored for movement over an extended period of time. The overall design of the tests, observed bond failures, and examples of on-going joint stability as related to adhesive usage (whether as primary adhesive or as a coating), solvent type, and solvent-to-solids ratios, will be reported. Future directions for more in depth and expanded evaluations will be discussed.

2005 | Minneapolis | Volume 12