The One wrote:
I really need a non-biodegradable, self-sealing, heavy-duty,
absolutely water-tight plasic bag, at least four feet by two feet
but I was unable to find anything like this from any packaging
supplier. I figure I can glue together two sides of a shower curtin
but I need an adhesive that is very secure and water tight. Home
Depot did not seem to have anything like this. Any ideas on what
product would work and where to get it ? Stephen

Consider can liners. Here's some:

three x four feet, 2 mil thickness (less than a shower curtain, but far
stronger).

http://www.toiletpaperworld.com/tpw/...05011-88%20GRA