you could buy some of that short infomercial rubber spray stuff that the guys uses over a screen door for a boat??!!
Actually, that doesn’t sound like to bad of an idea. In the video I saw a few years back, the guy used a can of liquid plastic. He poured it in a big tub and dipped his net bag into it, then hung it to dry over some newspapers making sure the bag wasn’t over lapping anywhere so it wouldn’t stick together.