Are you sure you are an engineer? Have you not heard of HDPE or high density polyethylene? This material is not only UV stabilised which means it does not fade or change colour, it has been independently tested to have five times the impact resistance of fibreglass. HDPE is used to make wheelie bins, pontoons, wheel barrows, plumbing supplies, polycraft boats to name a few... Sorry, just get a little annoyed by unqualified posts.
GSDogs