Bio-sourced nanocellulosic materials are promising candidates for spinning high-performance sustainable macrofibers for advanced applications. Various strategies have been pursued to gain nanocellulose-based macrofibers with improved strength. However, nearly all of them have been achieved at the expense of their elongation and toughness. Inspired by the widely existed hierarchical helical and nanocomposite structural features in biosynthesized fibers exhibiting exceptional combinations of strength and toughness, we report a design strategy to make nanocellulose-based macrofibers with similar characteristics. By combining a facile wet-spinning process with a subsequent multiple wet-twisting procedure, we successfully obtain biomimetic hierarchical helical nanocomposite macrofibers based on bacterial cellulose nanofibers, realizing impressive improvement in their tensile strength, elongation and toughness simultaneously. The achievement certifies the validity of the bioinspired hierarchical helical and nanocomposite structural design proposed here. This bioinspired design strategy provides a potential platform for further optimizing or creating many more strong and tough nanocomposite fiber materials for diverse applications.

中文翻译：

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基于细菌纤维素纳米纤维的仿生分级螺旋纳米复合材料粗纤维


生物来源的纳米纤维素材料是纺制高性能可持续粗纤维以用于先进应用的有前途的候选材料。人们已经采取了各种策略来获得具有更高强度的纳米纤维素基粗纤维。然而，几乎所有这些都是以牺牲伸长率和韧性为代价实现的。受到生物合成纤维中广泛存在的分层螺旋和纳米复合结构特征的启发，表现出强度和韧性的特殊组合，我们报告了一种设计策略，可以制造具有类似特征的纳米纤维素基粗纤维。通过将简便的湿纺工艺与随后的多次湿加捻工艺相结合，我们成功地获得了基于细菌纤维素纳米纤维的仿生分级螺旋纳米复合粗纤维，同时实现了其拉伸强度、伸长率和韧性的显着提高。该成果证明了此处提出的仿生分层螺旋和纳米复合材料结构设计的有效性。这种仿生设计策略提供了一个潜在的平台，可以进一步优化或创造更多坚固耐用的纳米复合纤维材料，以适应不同的应用。