Gel spun type material can work fairly well ..
for adding a ton of backing on to a reel. Two factors to keep in mind (this is from folks who have used same for this purpose):
1. Make darned sure you're got gloves on if you try to grab this line while it's moving ... it will saw your finger(s) off due to its small size.
2. If you don''t get a good lie/lay going onto your spool it can 'over wrap' it self and make a hell of a mess PDQ with a hot running fish.