Not bmx, but it is plastic - and that's definitely topical. And apparently it's quite light, so it's checking boxes there. Regardless, it's interesting - in a kind of freak show way:
This thing proves how much designers love plastic and that they will attempt to make everything and anything from it.
The guy responsible for this is an industrial designer named Matt Clark. His idea was to make a bike that uses mass production techniques rather than the laborious techniques of notching, aligning and welding tubes of aluminium, steel or whatever. And to combine that with a cheap material such as polypropylene so you end up with a super cheap bike frame that you could pump out in the hundreds of thousands. Theoretically.
An internal ribbing structure of thermoformed polypropylene is heat welded into each half of the frame, then along with a reinforce polypropylene insert in the chainstays, the two halves are fused together to create a cheap and rigid (?) ride.
Definitely no bmx application and possibly no real application at all, but there you go - designers like plastic.
And thanks to Errol at Everyone for the link.