Why isn’t polypro used as a core in surfboards. Beaded polypro is tough, has flex and memory and does not absorb water. Is it a matter of expense or is it a question of getting it to bond to traditional surfboard material? A lot of epoxy boards use EPS foam. It looks like the stuff they make $2.00 coolers out of! I have an EPS core in a longboard. Very floaty, but also stiff and chattery. Not ideal. Polyester/clark foam just feels the best to me in surfboards, but it alas breaks down, will absorb water over time if exposed to it. I have boogies with polpro cores and srtringered with graphite, they last almost forever - why not polypro in surfoards??
Polypropylene does have some interesting properties both extruded and beaded. Cost has been a factor in the past but seems to less of a factor now. The PP I’ve used has had water intrusion issues but here are today better PP materials out there. But finding them in the right size and right quality has yet to be done. Tom Morey does use some and Channin is working on some PP blanks as well. We have been working with some new resin formulations for the product, but wether it ever comes to market only time will tell. Bottom line here is that it has been looked at and will continue to be a product that may, in the future, be developed.