Epotek 302 and Epotek 730 UNF

Robert K. MacDowell <robert [at] rstarmail__com> writes

>We would be very interested to know if anyone has evaluated Epoxy
>Technology (Epotek) adhesives 302 and 730 UNF for use in bonding
>ceramics and glass and we are especially interested in the issues of
>color, yellowing, and how the adhesives resist being absorbed into
>the body of soft-paste and other porous ceramics.

I'd like to suggest you consider using acrylic adhesives rather than
epoxies. I think that the use of epoxies is overkill, especially on
porous ceramics. Testing has been done on B-72 as a structural
adhesive, and the research found that a blend of B-72 and B-48N was
nearly as strong as the epoxies tested (Epotek 301-2 was one of
them). The research was done on marble, but I believe these
adhesives are plenty strong to repair ceramics. Porous ceramics will
require a thin application of a barrier coat (10% B72 in acetone) to
seal the break edges to avoid "starving the joint." Once you trust
B-72 as a structural adhesive, you won't have to worry about
yellowing and other aging issues. See the following articles for B72
as a structural adhesive:

    Jorjani, M., G. Wheeler, C. Riccardelli, W. Soboyejo, N. Rahbar.
    2009.
    "An evaluation of potential adhesives for marble repair".
    In Holding it All Together: ancient and modern approaches to
    joining, repair and consolidation. Janet Ambers et al., eds.
    London: Archetype Publications.

    Note: Another version of this paper can be found in the OSG 2008
    Postprints, Vol. 15

    Rahbar, N., M. Jorjani, C. Riccardelli, G. Wheeler, I. Yakub, T.
    Tan, and W. Soboyejo. 2010.
    "Mixed mode fracture of marble/adhesive interfaces".
    In Materials Science and Engineering: A 527, no. 18-19:
    4939-4946. DOI: 10.1016/j.msea.2010-04-029.

    Podany, J., K. M. Garland, W. R. Freeman, J. Rogers. 2001
    "Paraloid B-72 as a structural adhesive and as a barrier within
    structural adhesive bonds: evaluations of strength and
    reversibility".
    Journal of the American Institute for Conservation, Vol. 40,
    No. 1, pp.15-33.
    <URL:http://cool.conservation-us.org/jaic/articles/jaic40-01-002.html>


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                  Conservation DistList Instance 26:46
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