Is it possible to use recycled plastic in the roto mold process?

Question

I was told virgin material only.

Answer 1

Who told you that?

Answer 2

The plastic has to be thermo-formable.

The "virgin material only" bit applies to injection molding, and even there, you can get away with 30% or so remix.

Virgin material adheres better to itself. Once it has been exercised, the only bonding really going on is mechanical (plastic wrapping around other plastic - as opposed to sticking to it).