Really interesting! I've been thinking if we could do our own acetate celluloid from cotton. Not an easy task, probably, but then it would be 100% home-brew .
I thought that the corona discharge subbing of polyester would be easy but it has proven to be quite tricky. I can't repeat the phenomena described in patents and still have problems with adhesion. PET is just so easily available as a modern plastic, that's why I'd like to use it.
Isn't triacetate more stable? I thought triacetate replaced diacetate for this reason.