While PP makes the "best" live hinges, any plastic that can form linear crystals (ie any plastic that makes good fibres) can make a reasonable live hinge. Nylon can work if it's other properties are OK. It will have limited hinge life compared to PP.
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I agree with Pat. Also, if you don't know nylons have very good resistance to automotive fluids such as gasoline / petrol. You can find a comparison of chemical resistance for many common thermoplastics at
Nylon becomes much softer and with better elongation to beak only after some time exposed to humidity in the air. That means it's not a good idea to flex the hinge straight from the mold, better to wait. Also you can speed up the flexibilisation by dipping it in water for some time.