Packing wet books

Linda A. Cranston <lcransto<-a t->longwood< . >lwc< . >edu> asked about the low
temperature strength of plastics packaging boxes, comparing milk
crates with the moulded storage boxes widely available.

I think there could be a problem with the storage boxes as they are
very competitively priced (in the UK) and made from polypropylene.
The lowest cost polypropylene is homopolymer, which loses its impact
strength very quickly at below freezing temperatures. Milk crates
were *traditionally* made from high density polyethylene which has
much better low temperature impact strength, so there is probably
something in the theory. As always, I guess the best way is to leave
a few crates overnight at the lowest temperature they are likely to
encounter, under a reasonable load, then impact them at that low
temperature and see what happens.

Colin Williamson

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                  Conservation DistList Instance 10:71
                 Distributed: Monday, February 10, 1997
                       Message Id: cdl-10-71-007
                                  ***