Storing photographic materials

Can somebody give me a information about which material is better
polyethylene or polypropylene as a storage pages for photographic
materials?

Maria Karen Sigurdardottir
Photographic conservator
Reykjavik Museum of Photography
Iceland

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                  Conservation DistList Instance 13:28
                 Distributed: Tuesday, November 2, 1999
                       Message Id: cdl-13-28-022
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