BEVA 371

David Laine <david.laine [at] freebel__net> writes

>According to Feller's classification of useful life, witch gives a
>very approximate indication of the stability of the polymer,
>Ethylene/vinyl acetate copolymers, such as BEVA 371,is classified as
>A, over 100 years....

In addition to David's comment on the stability of EVA co-polymers
as reported by Feller and Curran, the other major component of BEVA
371 is Ketone Resin N, a cyclohexanone polymer.  Other
cyclohexanones or methyl cyclohexanones may have been substituted in
the formulations currently available, as I have came across the
substitution of Ketone Resin N with MS2A in the dry-mix form of the
adhesive.  De la Rie has reported on the non-yellowing properties of
several methyl/cyclohexanones that were investigated through
light-aging experiments, although some increased absorption in the
ultra-violet region was noted:

    E. Rene de la Rie and Alexander M. Shedrinsky
    "The Chemistry of Ketone Resins and the Synthesis of a
    Derivative with Increased Stability and Flexibility"
    in Studies in Conservation, Volume 34, 1989, pp. 9-19.

The following published study reports on a perceptible yellowing of
BEVA film when subjected to light and UV aging:

    Jane L. Down, Maureen A. MacDonald, Jean Tetreault and
    R. Scott Williams
    "Adhesive Testing at the Canadian Conservation Institute--An
    Evaluation of Selected Poly(Vinyl Acetate) and Acrylic
    Adhesives"
    in Studies in Conservation, Volume 41, 1996, pp. 19-44.

Lawrence Chin
MA Conservation in Fine Art (Easel Paintings)
University of Northumbria at Newcastle


                                  ***
                  Conservation DistList Instance 14:41
                 Distributed: Monday, January 29, 2001
                       Message Id: cdl-14-41-002
                                  ***