If you've got some Teflon on hand, by all means give it a try and monitor it. With intermittent contact between it and the chain cold flow may not be an issue.

https://en.wikipedia.org/wiki/Creep_(deformation)

There are soooooooooo many different plastics available (I know a chemist who specializes in plastics) so garage tinkerers like us have our work cut out to try and pick an appropriate materials. Some of them absorb water (and change size while doing it), others cold flow, some are a PITA to machine (you may need to freeze them first). Garden variety acetal may not have the same properties as a name brand version (Delrin) but does it make a difference in our applications? UHMW-PE is what was recommended to me for one-off rub strips by that road-racing chemist but it wouldn't surprise me if there was something even better that I've never heard of.

I think we are all well advised to make our best selection of a material and then keep an eye on how things are holding up for "just in case" issues. PTFE may be great stuff on cookware, but that doesn't mean it is ideal for using on a motorcycle (maybe if you use bacon grease to lube the chain . . .).

cheers,
Michael