The link here is to a company that makes peal on UHMW for several different applications. Seems to me, one could just order this stuff in the right width & thickness (upto 1/8" I believe) and put it on the bottom of a canoe as a low friction, sacrifical, abrasive surface. My only concern would be that the edges would peal away during a bottom dragging event. If your're thinking about using it, let us know your experience & what Crown Plastic has said about this type of application.
I'm suppose to be getting a heavy fiberglass canoe this winter, so maybe I'll give it a go.
Here's the link on how it is applied. The material in the video seems thin, but like I said you can get thicker.