[Nhcoll-l] Potential problem with older PE jar lid liners

[Jean-Marc Gagnon]

Paul,

At the Canadian Museum of Nature, we have been using F217 PE Seals for a good 20 years and have not observed deterioration. This is not to say that we have checked all lids with such gaskets installed since that time, but we have had the opportunity to open quite a few.

As Stott Williams indicated, there may certainly be differences between batches, as it's been for instance observed for batches of Ethafoam and other closed-cell polyethylene products.

While it is still hard to predict the long-term durability of PE seal, the use of a good sealing tape around the lid can certainly serve to at least partly mitigate this problem and insure the preservation of the collection specimens (Steigerwald, Michele and Sylvie Laframboise, 1996. Tape application: a jar sealing method for reducing ethanol evaporation in fluid-preserved collections. Collection Forum 12(2): 45-53).

Jean-Marc

Jean-Marc Gagnon, Ph.D.
Past President (2012-2014) of the Society for the Preservation of Natural History Collections (www.spnhc.org<http://www.spnhc.org/>)

Curator / Conservateur des collections
Invertebrate Collections / Collections des invertébrés
Canadian Museum of Nature / Musée canadien de la nature
P.O. Box 3443, Stn "D" / C.P. 3443, Succ. D
Ottawa, ON Canada K1P 6P4
T: 613-364-4066 / F: 613-364-4027
E/C: jmgagnon at mus-nature.ca<mailto:jmgagnon at mus-nature.ca>
http://www.nature.ca<http://www.nature.ca/>

From: nhcoll-l-bounces at mailman.yale.edu [mailto:nhcoll-l-bounces at mailman.yale.edu] On Behalf Of Paul Callomon
Sent: July-30-12 3:56 PM
To: NH-COLL listserv (nhcoll-l at mailman.yale.edu)
Subject: [Nhcoll-l] Potential problem with older PE jar lid liners

Colleagues,

I have today found a severely deteriorated jar lid liner in our alcohol collection. The liner is made from polyethylene foam. It was sold to us in 1999 and installed in 2000. The material has failed completely, with crazing and cracking of the surface and tearing along the compression face. The foam has become weak and powdery in places. The jar was filled with 70% ethanol.

The manufacturers have suggested that the use of this liner for long-term storage of alcohol is responsible for the deterioration. If this is true, the implications for our collection - we have about 20,000 bottles that use these liners - are potentially serious.

Does anyone have experience with this problem? Are Teflon liners a better alternative?

Paul Callomon
Collections Manager in Malacology, Invertebrate Paleontology and General Invertebrates
The Academy of Natural Sciences of Drexel University
1900 Benjamin Franklin Parkway
Philadelphia, PA  19103
callomon at ansp.org<mailto:callomon at ansp.org>
Tel. 215-405-5096
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