I bought some gore tex thread some time ago for use on my biminis.

A seam on my 16 whalers bimini finally separated and I decided to try
out the gore tex thread. Gore tex thread (aka tenara) is like 10x the
cost of polyester and has a lighter initial breaking strength. I have
been doing basic repairs to sails and tops with V-69 polyester but
because goretex does not rot in the sun like the polyester does they
say you can use a lighter weight and get away with it. I want to
recall reading that the stuff was difficult to stitch with and that may
be why I have passed up other opportunities to experiment with it but
to my surprise I had NO problems with it running through my old Kenmore
sewing machine. When filling the bobbins the thread felt very
inconsistant and uneven (lumpy!) but to my surprise I had no problems
working with it !