In Chicago, a plastic has been developed that can be hard or soft depending on the temperature at which it is synthesised. A useful tool for a trip to Mars?

For more than three thousand years, metalworkers have played with temperature to adjust the hardness of iron alloys. But in the world of plastics, people have tended to look for a polymer with the best physico-chemical properties for each application. That’s fine as long as you can order the ideal plastic from the factory, but it gets tricky when you want to make your own spare parts with a 3D printer. Especially if you’re in the middle of the ocean or in a spaceship with a limited collection of plastic filaments.