Sciencemadness Discussion Board

Alkali-hydroxide-stable, conductive membranes from cross-linking polyvinyl alcohol

Melgar - 26-3-2017 at 16:17

I know plenty of people here have been interested in polymeric membranes for divided-cell reactions, and the attached NASA paper discusses three ways to make them from polyvinyl alcohol, as well as the properties of the resulting film.

They used three different methods to do the crosslinking, first with gluteraldehyde, then by using periodic acid to cleave the 1-2% of the sites where diols exist, which is apparently an impurity in commercial samples that they took advantage of. The last method used radioactive water, which I'll assume is outside of what people here have access to. The most conductive membranes were those made with gluteraldehyde, because they could be controlled best, but the ones made by cleaving diol sites apparently were acceptable and tended to be more durable.

Seems promising. Incidentally, I wonder if it'd be possible to use diisocyanates as cross-linking agents for PVA? It could just be sprayed on in a diluted form, and diisocyantes are one of the two parts in two-part polyurethane foam mixtures.

I posted this in the organic chemistry forum, but I just realized most of the electrolytic stuff is here, so I figure I should post it here too.

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