The high toughness of natural spider-silk is attributed to their unique β-sheet secondary structures. However, the preparation of mechanically strong β-sheet rich materials remains a significant challenge due to challenges involved in processing the polymers/proteins, and managing the assembly of the hydrophobic residues. Inspired by spider-silk, our approach effectively utilizes the superior mechanical toughness and stability afforded by localised β-sheet domains within an amorphous network. Using a grafting-from polymerisation approach within an amorphous hydrophilic network allows for spatially controlled growth of poly(valine) and poly(valine-r-glycine) as β-sheet forming polypeptides via N-carboxyanhydride ring opening polymerisation. The resulting continuous β-sheet nanocrystal network exhibits improved compressive strength and stiffness over the initial network lacking β-sheets of up to 30 MPa (300 times greater than the initial network) and 6 MPa (100 times greater than the initial network) respectively. The network demonstrates improved resistance to strong acid, base and protein denaturants over 28 days.

天然蜘蛛丝的高韧性归因于其独特的β-折叠二级结构。然而，由于加工聚合物/蛋白质以及管理疏水残基的组装所涉及的挑战，机械强度高的富含β-折叠的材料的制备仍然是重大挑战。受蜘蛛丝的启发，我们的方法有效地利用了无定形网络中局部β-sheet域提供的卓越的机械韧性和稳定性。使用无定形的亲水网络内的接枝-从聚合方法允许聚空间受控生长（缬氨酸）和聚（缬氨酸- [R-甘氨酸）通过N-羧酸酐开环聚合形成β-折叠片。所得的连续β-折叠纳米晶体网络在初始网络上显示出改进的抗压强度和刚度，而缺少分别高达30 MPa（比初始网络大300倍）和6 MPa（比初始网络大100倍）的β-薄片。该网络在28天内显示出对强酸，碱和蛋白质变性剂的增强抗性。