TEST FOR COMPATIBILITY WITH ORGANIC HERITAGE MATERIALS – A PROPOSED PROCEDURE

To evaluate the compatibility of conservation and storagematerials with heritage objects of organic origin, a newtest method is proposed.The test is performed in closed vials at 100oC for 5 dayswith the tested material and a reference paper in the vial.Volatiles off-gassed from the tested material may causedegradation of the reference paper and lead to a decreasein its degree of polymerization. This is determined usingviscometry. The optimal vial type is proposed, leading toreproducible results with a standard deviation for three parallelexperiments typically under 2%. The selected referencematerial, Whatman No. 1 filter paper, being made ofpurified cotton linters, is susceptible to volatiles promotingboth hydrolytic and oxidative degradation, and its responseto tested materials is thus likely to be relevant to a widevariety of heritage materials and objects of organic origin.The case studies show possible uses of the proposedmethod, and a pronounced pro-degrading effect of groundwoodcontaining paper on the reference paper is shown, avariety of combinations of rag, groundwood and recycledpapers were studied and a number of cardboards used forwrapping or for boxes were evaluated.The new test is proposed as a repeatable, inexpensive andrapid method of assessment of compatibility of materialsused for housing or display of heritage objects of organicorigin, thus enabling conser vators, providers of conservationmaterials and collection managers to make betterinformed selection of appropriate housing or display materials.