Preserving plastic

Danelle Orange <daorange [at] dwu__edu> writes

>I have several donations of plastic signs and bags from the 1970s
>that we need to keep. ...
>...   There is very
>little indication of what types of plastic and dyes were used to
>create the items. What would be the best way to preserve these?

It is my understanding that in most cases the primary chemical
changes leading to the degradation of plastic are as a result of
oxidation.

One of the methods suggested for preventing or reducing oxidation is
to store the artefacts in an oxygen--free (anoxic) environment. This
can be easily produced by storing the artefacts in an enclosure
(bag) made of barrier film (for example Escal), along with the
appropriate oxygen absorbers (Ageless or RP System).

More information on oxygen free storage is at
<URL:http://www.keepsafe.ca>  Unfortunately this new iteration of
the keepsafe website is still under construction. so I would be
happy to personally answer any inquiries.

I might also suggest an excellent article by Scott Williams of the
Canadian Conservation Institute: "Composition Implications of
Plastic Artifacts" published in "Saving the Twentieth Century: The
Conservation of Modern Materials" (pages 135-153).

Jerry Shiner
Keepsafe Microclimate Systems
416-703-4696


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                  Conservation DistList Instance 22:41
                Distributed: Wednesday, January 21, 2009
                       Message Id: cdl-22-41-003
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