On 04/28/2017 09:20 AM, Al Kossow via cctalk wrote:
  I wish I knew of a gasket material I could trust to
survive.
 Norprene is polypropylene based, as opposed to PVC, polyurethane,
 etc.
 Home weather stripping is made from polyurethane.
 This is the stuff I'm going to try
 
http://www.ebay.com/itm/281947335227 
It's hard to beat butyl foam rubber.  They build boats with it--and I
think it's also used on lab equipment where contact with corrosive
solvents is anticipated.
It's expensive, though.
--Chuck