Anoxia and plastics

Ingrid Neuman <berkart [at] earthlink__net> writes

>I am curious if anyone has thought about, is looking into or
>currently experimenting with anoxic encapsulation of small
>contemporary art pieces composed of plastics (in Escal for instance
>with Ageless) in order to slow down the rate of deterioration of
>certain types of polymers? ...

Any reduction in temperature possible will slow deterioration, so
where possible, cold or cool storage will help, keeping in mind that
plastics become brittle at low temperatures.

I am looking into storing the occasional polymer material showing
serious deterioration sealed in Mylar with Ageless and placed in the
freezer, to exclude both oxygen and light, and keep temperatures
low. Another concern with some plastics is the presence of water, as
they can undergo hydrolysis reactions. In this instance silica gel
may be needed in the enclosure, as Ageless affects humidity levels
(as well as heating up as it absorbs oxygen, another concern). Along
these lines, rubber and some other materials will off-gas sulphur
compounds as they deteriorate, which could increase deterioration,
especially in a sealed environment, and may require a pollution
absorber enclosed with the object.

I have not done any controlled studies to determine how these
factors affect rates of reaction, but according to literature, these
measures should reduce deterioration. It would be interesting to
look into this if suitable material for experimentation could be
found. Keep me posted.

Valerie Tomlinson
Conservator
Auckland Museum
Tamaki Paenga Hira
The Domain
Private Bag 92018
Auckland 1142, New Zealand


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                  Conservation DistList Instance 25:5
                   Distributed: Tuesday, July 5, 2011
                        Message Id: cdl-25-5-001
                                  ***