Abstract In aramid nanofiber (ANF) films, the chemical interactions between individual fibers are mainly hydrogen bonds that formed in C=O and N-H, which are highly ordered and ensure the high strength and modulus of ANF paper. In this work, the ANF is firstly hydrolyzed in NaOH aqueous solution to realize carboxylation. Subsequently, the carboxylated ANF is covalently crosslinked by bio-inspired polydopamine (PDA) and assembled to be a paper-like film through vacuum filtration. Compared to pure ANF and un-crosslinked PDA-ANF films, the covalently crosslinked composite film shows an improved mechanical strength and toughness simultaneously. This indicates that the covalent bonds are more useful than hydrogen bonds on improving the mechanical properties of ANF paper.

中文翻译：

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芳纶纳米纤维薄膜的仿生共价交联以提高机械性能

摘要 在芳纶纳米纤维（ANF）薄膜中，单根纤维之间的化学相互作用主要是在C=O和NH中形成的氢键，它们高度有序，保证了ANF纸的高强度和高模量。在这项工作中，ANF首先在NaOH水溶液中水解以实现羧化。随后，羧化 ANF 被仿生聚多巴胺 (PDA) 共价交联，并通过真空过滤组装成纸状薄膜。与纯 ANF 和未交联的 PDA-ANF 薄膜相比，共价交联复合薄膜同时显示出改善的机械强度和韧性。这表明共价键在提高 ANF 纸的机械性能方面比氢键更有用。