Ethafoam

We seem to have a large quantity of Ethafoam in artifact storage
areas that is deteriorating.  It still appears sound, but if one
presses a finger into it, the product compacts and crushes, leaving
a hole where the finger was inserted.  It also leaves a white powder
on the finger and surrounding areas.  I believe, but am not 100%
sure, that this Ethafoam was purchased about 15 years ago when there
was a large storage project underway that included making custom
Ethafoam inserts for a huge number of drawers and shelving units.

I contacted Dow Canada to enquire about the problem and was told
that this was the first they have heard of it.  I asked if the
problem could be associated with a change in blowing agent,
instigated by the move away from CFC's around that time.  The
representative emphatically stated that the blowing agents, several
of which have been used over the years, are all inert and should not
cause any breakdown of the polyethylene.  I asked if they had
subcontracted out the manufacture of Ethafoam at some point, and
perhaps lost some control over the production methods and was told
that manufacture of Ethafoam has never been farmed out.  All they
could suggest is that we had purchased something marketed as
Ethafoam, but which was, in fact, another product.  I'm not ruling
out this possibility, since there don't seem to be any records of
the purchase that might confirm the product's identity.

I'm interested in finding out if anyone else is having this problem
and if so, have you determined that it is, in fact, true Ethafoam
that is breaking down?  Is there a way of predicting the progress of
deterioration?  Is there a way of identifying the "bad" foam?  And
one other question... in at least one case, the "bad" foam is
surrounding some small tools which are covered with surface rust.
Could the foam be off-gassing and causing the corrosion? Your
anecdotes and/or research would be most appreciated.

Kasey Brewer
Head of Conservation
Royal British Columbia Museum
675 Belleville Street
Victoria, BC   V8W 9W2
Canada
250-387-5518
Fax: 250-356-8197


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                  Conservation DistList Instance 19:12
                Distributed: Wednesday, August 31, 2005
                       Message Id: cdl-19-12-012
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