This is specifically a biodegradable polyurethane. It's just one kind of plastic and not suitable for everything.
We have others including old stuff like cellophane, pPLA, PGA, PGL, PHB even biodegradable polyesters... They're cheap. They can be fiber reinforced as needed. However...
The tricky bit is that almost always they need to be properly composted to decompose. This is called procedure 7 and cannot be usually applied to plastics that have a pigment added or are painted - the additives would poison the compost heap or leech. You need to be particularly choosy about paints and plasticizers if you want it to decompose safely.
We have others including old stuff like cellophane, pPLA, PGA, PGL, PHB even biodegradable polyesters... They're cheap. They can be fiber reinforced as needed. However...
The tricky bit is that almost always they need to be properly composted to decompose. This is called procedure 7 and cannot be usually applied to plastics that have a pigment added or are painted - the additives would poison the compost heap or leech. You need to be particularly choosy about paints and plasticizers if you want it to decompose safely.