Wet bag - material to keep the smell in?

[principii]

I've been digging around online this morning, trying to find what type of material actually keeps the smell in the wet bag, but I haven't had much luck! I'd like to make some for myself (though yes, I'm drooling over Blueberry's minky bags, LOL) ... but seeing as how I'm stuck at step one, finding material, I thought I'd turn to y'all here, The Diaper Gurus.

Help, anybody? TIA!!!

[funkymamajoy]

I use a boiled wool wet bag that is pretty heavily lanolized on the inside. Doesn't smell at all.

[DizzySkunk]

I just use a freezer ziplock bag. Note: FREEZER, not sandwich... the plastic seems to be better.