Dear Sara:
 
Please check the following websit: <http:// www.spnch.org/concorn/suppliers-cdn.pdf.>
This websit provides very practical, and useful information about supplies and materials for museum collections.
 
Coroplast composed of 90% food-grade polypropylene and 10% polyrthylene, looking like a plastic version of corrugated cardboard. The uncoloured translucent is marketed as "archival", and said to be free of colouring agents, and anti-static and ultraviolet inhibitors. But it may degrade when exposed to sunlight. Coroplast is said to offer 15-20 years protection for non-ferrous mentals.
 
It is very easy to make any shape of storage box with coloplast, boxes can be constructed by screwing, rivetting, stitching, trying with cotton tape, glueing with hot-melt Japanese rice glue, or using staple or plastic fasteners.  Chemically, they have no difference between per-made, custom made  box , or  board itself.
 
Correx is very similar to Coroplast, they have different trade name and  each produced different densities, and thicknesses to suit their buyers.
 
Best Wish,
jiuan lin