Gaskets and alcohol

Louis Sorkin <sorkin [at] amnh__org> writes

>Does anyone have any information on gaskets and alcohol storage (for
>specimens)?  ...
>...
>...  The gasket can
>become gooey, hardened, discolored and the alcohol also discolors
>and becomes "greasy" or cloudy. ...

I have come across this problem before with Le Parfait jars which
fit the description of Mason jars.  The older-style rubber gaskets,
for use in museum fluid collections, have been superseded by black
coloured gaskets  of EPDM (Ethylene-propylene-Diene-monomer) and
these should not leach phthalates or lead to discolouration,
vulcanisation, etc.  As for tubes, I never use any form of bung
except those made from nylon.

Simon Moore MIScT, FLS, ACR
20 Newbury Street,
Whitchurch RG28 7DN


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                  Conservation DistList Instance 23:20
                 Distributed: Sunday, December 6, 2009
                       Message Id: cdl-23-20-005
                                  ***