HDPE for side bending forms

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I have not come across that process before, and don’t profess to be very knowledgeable about plastics. From my understanding, Corian is very dense and rigid as far as plastics are concerned, and so if it can be heat bent to suit this purpose, it should retain its shape and strength well. Even though HDPE is dense as far as PEs are concerned, I think that its rigidity/strength would be questionable if used the same way.

HDPE will thermo-form at around 250F to 300F depending on how HD it is. It should be quite non-stick too for gluing up laminates.
True about the rigidity problem, it will be flexible. Maybe you can solve that with some type of frame under it

Just watched a YouTube vid of a kid making HDPE sheets out of milk bottle and soda bottle tops. His mum is a star - he melts the stuff in the household's domestic oven!