Polyurethanes are nearly everywhere, but these highly versatile materials can have a major downside. Derived from crude oil, toxic to synthesize, and slow to break down, conventional polyurethanes are not environmentally friendly. Now, researchers discuss devising what they say should be a safer, biodegradable alternative derived from fish waste -- heads, bones, skin and guts -- that would otherwise likely be discarded. The researchers will present their results today at ACS Spring 2021.