Spiders silks have extraordinary strength and toughness simultaneously, thus has become dreamed materials by scientists and industries. Although there have been tremendous attempts to prepare fibers from genetically manufacture spider silk proteins, however, it has been still a huge challenge because of tedious procedure and high cost. Here, a facile spider-silk-mimicking strategy is reported for preparing highly scratchable polymers and supertough fibers from chemical synthesis route. Polymer films with high extensibility (>1200%) and supertough fibers (~387 MJ m-3) are achieved by introducing polypeptides with β-sheet and α-helical structure in polyureathane/urea polymers. Notabley,the toughness of the fiber is more than twice the reported value of a normal spider dragline silk, and comparable with the toughest spider silk, aciniform silk of Argiope trifasciata.
Quantifying the fraction of glycine and alanine in β-sheet and helical conformations in spider dragline silk using solid-state NMR