While accelerated aging tests have been used for paper for several decades, there has been no systematic study to see if a similar test at elevated temperatures and a controlled relative humidity level can be used to predict the life of adhesives used in bookbinding.
A study conducted by the Preservation Directorate of the Library of Congress will determine whether a scientific basis exists for developing an accelerated aging test for polyvinyl acetate adhesives (PVA). Arrhenius plots, determined over a range of aging conditions, will establish whether the degradative reactions that occur at a higher speed at elevated temperatures are the same as the ones that prevail at lower temperatures.
Significant progress has been made in this project. A series of test samples, constructed from buckram and crash (both fabrics used in book structure) joined by two different PVA adhesives, are being aged under a wide range of aging conditions. The effect of the aging process upon the adhesive joint will be measured by a peel test. Conformance of these data to an Arrhenius relationship will demonstrate the validity of the accelerated aging process. These experiments will also determine whether the adhesive benefits from a deacidification treatment. Samples with and without Bookkeeper deacidification treatment are being tested.
Reprinted from Int. Presn. News #17, May 1998.