Plastics and storage

On behalf of Maryly Snow <slides [at] ced__berkeley__edu>
  Ann Swartzell <aswartze [at] library__berkeley__edu> writes

>I need some advice on the relative merits of three different plastic
>materials, ABS, polycarbonate, and phenolics.

I would recommend ABS plastic dividers out of the three choices that you
mentioned for the slide drawers.  ABS is susceptible to degradation by
UV light, which should not be a problem in this application.

Polycarbonate is attacked by alkalis, ammonia and other amines.  Light
and humidity levels need to be minimal.  Solvents such as acetone can
cause stress cracks.

Phenolics have poor moisture-resistance, and are sensitive to acids,
alkalis and solvents.

Your best choice in my opinion, would be Coroplast corrugated boards.
These are composed of a stable polypropylene/polyethylene copolymer.
They are available in several thicknesses (2-6mm) and colors.  The
colorants are stable.  Cor-X and PolyFlute are analogous products.  The
coroplast is very easy to cut and is recommended for storage box
construction (see references below).  Check with local plastic suppliers
for availability or contact Coroplast directly.  For detailed drawings
and further information on cutting and bonding the sheeting see

    Storage of Natural History Collections: Ideas and Practical
    Solutions. C.L. Rose and A.R. Torres, editors, SPNHC, 1992;

and

    Technical Bulletin 14: Working with Polyethylene Foam and Fluted
    Plastic Sheet. Carl Schlichting, CCI, Ottawa, Canada, 1994.

Paul S. Storch
Objects Conservator
Minnesota Historical Society
bm.mha [at] rlg__stanford__edu

Michael Fox
Head of Processing
Minnesota Historical Society

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                  Conservation DistList Instance 8:29
                 Distributed: Tuesday, October 25, 1994
                        Message Id: cdl-8-29-001
                                  ***