I know that plastics (polyurethane, polystyrene, polyethylene, etc) are very different from one another.

What I’ve been thinking about is, would it be possible to make some sort of powder with a mix of all these plastics, that could then be mixed with a binding agent to make bricks, plates and other, well, plastic things?

For anyone wondering “why”, this is a recycling idea, one that, if simply mixing in some binding agent (glue) works, or some glue + another plentiful material (dirt? sand?), wouldn’t need heat to give reuse to the plastics, thus eliminating a possible source of toxic fumes and allowing PVC to be thrown into the mix.

I know it is possible to do something like this with heat. You need to heat the mixture, usually to ~300º C, so once the molten plastic cools, most everything is stuck together. Such examples are plentiful around the internet. That’s why I wanna know if there’s a way to do it without using heat