Subject: Paleo-Bond
Diana Komejan <dandi [at] tallships__ca> writes >Does anyone have any information of an adhesive called Paleo-Bond? >Specific it has been recommended as a filler and adhesive for >Mammoth Ivory. Is this an appropriate adhesive? **** Moderator's comments: Paleo-Bond is a a product of: Uncommon Conglomerates, Inc. 400 Western Ave. N. St. Paul, MN 55103-2257 651-227-7000 Fax: 651-227-6526 800-323-4545 <URL:http://www.uncommonconglomerates.com/paleobond/> This is in response to Diana Komejan's request for information on Paleo-Bond adhesives. CCI has been looking into cyanoacrylate (CA) adhesives over the last few years. Ann Elder from the Dinosaur National Monument in Utah and myself were trying to obtain a NCPTT grant to study these adhesives for paleo collections but we were unsuccessful. These adhesives are being used for paleo collections very frequently but the long term aging studies have not been done. In the process of writing the grant application, we did a thorough literature review on the subject. We found that the medical profession has done the most work in this area for tissue closure and bone fractures. They discovered that ETHYL CA adhesives degrade very quickly causing dermatitis from the toxic byproducts. On the other hand, the BUTYL CA were found to degrade slowly enough to allow the body to absorb the degradation products and these are the CA adhesives that are now being used in the medical profession. Most testing was done in saline type solutions which, of course, are not the conditions that are found in a museum. Most commercially available types of CA adhesives in North America are the ethyl CA type including Paleo-Bond (some varieties of CA contain poly(methyl methacrylate) or silica as a thickener). I am hoping to start a small project on CA adhesives in the next year or so comparing the ethyl and butyl types under various relative humidities and UV light. Humidity and light seem to be the big deteriorating factors for CA adhesives. Whether the humidity found in a typical museum will degrade the CA to the point that it is unsuitable as a long-term adhesive choice is not known at this point in time. Perhaps the butyl variety will be more suitable than the ethyl variety. Vestergaard and Horie did a study on five adhesives, which included an ethyl CA adhesive, for a mastodon tooth which might be of interest to Diana (references below). They found that the CA filled the gap, suffered internal shrinkage cracks, and had strong joins (epoxy was the strongest). I believe they favoured the poly(vinyl acetate) as the best overall. If anyone would like more information on CA adhesives, please do not hesitate to contact me via email or by telephone 613-998-3721. References: Vestergaard, I.K.L. "Physical and Chemical Changes of Fossil Tooth Material by Use of Adhesives", Thesis, Goteborg University, Institute of Conservation, Goteborg, Sweden, (1994). Vestergaard, I.K.L,. and C.V. Horie. "A Comparison of the Interaction of Five Adhesives with Mastodon Tooth Adherends." In: Preprints of ICOM Committee for Conservation, II (1996) pp. 938-943. Jane Down Senior Conservation Scientist, CCI *** Conservation DistList Instance 14:56 Distributed: Monday, April 23, 2001 Message Id: cdl-14-56-007 ***Received on Friday, 20 April, 2001