Polystyrene beads

Can anybody assist with a reference or advice on the long term
chemical stability polystyrene beads.   At present polystyrene beads
(sealed within pillows made from polythene or cotton) are being used
as supports during treatment and as packing during transportation.

The museum will soon be moving it's collections into a new building
after which there will be a large number of these pillows which may
be reused for long term supports.

I have received mixed opinions re the chemical stability of
polystyrene.  My conclusions are this material is stable enough for
short term use (eg to support objects during treatment) but not for
long term storage because it degrades and/or may react with some
materials.

Colleagues tell me there has been research on this topic but we
cannot find a reference.

Any help would be very much appreciated, thank you in advance

Tony Clarke
Preventive Conservator
Museum of New Zealand
Wellington
New Zealand

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                  Conservation DistList Instance 10:38
                 Distributed: Monday, October 14, 1996
                       Message Id: cdl-10-38-002
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