Fig. 7. Compressive mechanical properties of the collagen sample and biomimetic UHANWs/Col porous nanocomposite with 66.7 wt% UHANWs: Stress–strain curves (a and b) and Young's modulus (c and d) of the freeze-dried porous nanocomposite (a and c) and rehydrated porous nanocomposite (b and d).