[NHCOLL-L:3505] Re: Neoprene rubber stoppers

[Mark O'Brien]

Brad:

After having to replace about 70,000 gray EPDM  stoppers (sold by West, and
we should have sued them) and  3 dram vials in our collections with 4 dram
vials with screwtop polyseal closures, I can tell you that rubber stoppers
of any kind are to be avoided.  Although the real neoprene stoppers tend to
have quite a long life, they are not archival, and they do not always fit
the vials properly, etc.  In our case, the EPDM materials oxidized and the
part exposed to the air melted after 15+ years of use.  My suggestion is to
make the switch to the screw top glass vials  and use bakelite tops with the
polyseal cone liners.  M Jacobs and Sons  in Detroit, MI sell them in bulk
at a fraction of the cost of places like VWR, etc.

Mark

---------------------
Mark F. O'Brien, Collections Manager
Insect Division, Museum of Zoology
2053 Ruthven Museums
University of Michigan, Ann Arbor, MI 48109-1079
734-647-2199
----------------------



On 7/25/07 10:54 AM, "Brad Hubley" <bradh at rom.on.ca> wrote:

> Hi all;
>  
> I'm searching for a supplier of neoprene rubber stoppers for our glass vials.
> We used to purchase our stoppers from West Pharmaceutical but have been told
> that they no longer supply them.  I have tried a number of other sources
> (Plasticoid, VWR Scientific, BioQuip, etc.) but have come up short, mainly
> because the length of our stoppers are what is proving to be problematic.  The
> dimensions of our stoppers are 16 mm top diameter x 12 mm bottom diameter x 20
> mm length and the samples I have been provided are 25 mm in length (or
> longer).  (If you need to see what kind of stoppers I'm talking about then go
> to http://www.vwrcanlab.com/catjpg/y01/y0155.jpg).  I'm concerned that if I go
> with the longer stoppers, that the bottom of the stoppers will expand in the
> vials over time making them almost impossible to get back into the vials
> (we've encountered this on a regular basis with stoppers that are pushed too
> far into vials).
>  
> If you have any suggestions as to suppliers, could you please let me know?
>  
> Many thanks,
> Brad
>  
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>   Brad Hubley
>   Entomology Collection Manager
>   Department of Natural History
>   Royal Ontario Museum
>   100 Queen's Park, Toronto, Ontario
>   Canada    M5S 2C6
>  
>   Phone:  1-416-586-5764
>   FAX:      1-416-586-5553
>   email:  bradh at rom.on.ca
>   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 


-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.yale.edu/mailman/private/nhcoll-l/attachments/20070726/276d31c4/attachment.html