Always had me thinking(and yes i do think occasionally
) about how boards are constructed and if there are any other alternatives out there that could be used
Wouldn't it be great if you could just pop boards out of a mold that need virtually no labour to build are reasonably light and stiff and will outlast anything out there today.
I wonder how Nylon 6 would fo as a board material? i know the small nylon gears made out of it are extremely light. 
Nylon 6 is the most common commercial grade of molded nylon. Nylon is available in glass-filled variants which increase structural and impact strength.
The gears might be light, but would the same volume of a board be lighter than what we have now?
You could always weigh those gears and work out their volume and compare.
Styrofoam is incredibly light, so I think it would take something special to beat the weight and strength of current boards.
First google result shows me it is a bit over 1 gram per cubic centimetre - same as water.
So an 80L board would weigh 80kg if it was solid.
If moulded, like old polyethylene boards, it would be pretty much the same weight as them - and weight is why they faded away.
Also, regardless of glass filling it would be more flexible than sandwich laminates .... that is simple engineering - a laminated structure is stiffer.
So yes you could use it, but you'd have something that was basically a Bombora Trifin but made out of recycled VCR gears.
Nylon absorbs water
Why not look for a nature product that is renewable. The way BP is wasting oil at the moment composite are going to get very rare and expensive.
There is a lot of interesting stuff being done with plant based epoxy and nature fibres to replace glass.
