Case for displaying architectural models

The Museum of Fine Arts Boston intends to display an architectural
model in a temporary exhibition. The model, made in 1974, was
constructed from painted wood, acrylic and polystyrene sheet, and
metal mesh. In order to ensure a safe display and protect the model
from fluctuations in humidity in the gallery, we are considering
exhibiting the model in a sealed case with a silica compartment.

This sealed environment would not allow ventilation for potential
off-gassing of degradation products from the plastic components. In
your experience, do acrylics and polystyrene release a considerable
amount of degradation products almost 40 years into their existence?
Could activated carbon in the display case absorb these degradation
products? And how can we detect and monitor the potential release of
the degradation products?

We would greatly appreciate learning from of your experiences in
this area. Please do not hesitate to contact us if should you have
questions or require further information.


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                  Conservation DistList Instance 27:18
                Distributed: Thursday, October 24, 2013
                       Message Id: cdl-27-18-020
                                  ***