sploople

Thanks for the quick response. Is this to say that even a layered membrane, such as the suggested mylar and kevlar, or something similar to that of vacuum pack bags, wouldn't hold for 10 years? Would they even hold for 1 year?

Insane Alien... thanks for the tips! Let me put some bounds on the requirements of this material. Say we can produce a high to ultra high vacuum with this material while it is placed over an internal skeleton... Is there a material that would hold for a decade before it leaked in enough atmospheric gases to be lowered to a medium vacuum? We have been tinkering with a small experiment in my mom's kitchen, and are now curious as to how long a vacuum bubble would last!! THANKS FOR THE HELP!

Newb here... didn't know where else to post this.... I realize there are rigid solids that will hold a vacuum for a very long time, but is there any flexible plastic or fabric that will hold a medium vacuum for a very long time? Another way of asking this... is there a plastic -- or even a coating that can be applied to a plastic-- which will not allow any molecules found in the atmosphere through? An actual zero-permeable material? How long will the bags used in vacuum food storage hold their vacuum?