How to overcome the dilemma between self-healing capacity and the mechanical strength for polyurethane materials is an intriguing but challenging topic. Taking advantage of the nano-scaled dispersion of the lignosulfonates in tailored waterborne polyurethane (WPU) emulsion, herein an aqueous dispersion strategy was proposed. Different from the previously reported methods, it is simple, efficient and environmentally friendly. The prepared self-healing polyurethane exhibited an ultra- high tensile strength of 51.4 MPa (higher than previously reported results) combined with a elongation at break of 670% when merely 6 wt% of lignosulfonate was introduced into the WPU system. Upon undergoing three cycles of thermal processing, a tensile strength higher than 30 MPa was still remained. Atomic Force Microscope (AFM) combined with Variable-Temperature Infrared Spectroscopy (V-FTIR) confirmed the existence of the nano-scaled lignosulfonate aggregates within the WPU matrix and the reinforcing mechanism was discussed from a viewpoint of the intermolecular interactions. V-FTIR further revealed the origin of the self-healing from the detected dissociation of the oxime-carbamate bonds with the increased temperature. This nano-scaled aqueous dispersion strategy demonstrates a high potential in designing polyurethane materials with balanced self-healing performance and mechanical properties.

如何克服聚氨酯自愈能力与机械强度之间的困境材料是一个有趣但具有挑战性的话题。利用木质素磺酸盐在特制水性聚氨酯 (WPU) 乳液中的纳米级分散性，本文提出了一种水性分散策略。与之前报道的方法不同，它简单、高效且环保。当仅将 6 wt% 的木质素磺酸盐引入 WPU 系统时，制备的自修复聚氨酯表现出 51.4 MPa 的超高拉伸强度（高于之前报道的结果）和 670% 的断裂伸长率。经过三个循环的热处理后，仍保持高于30 MPa的抗拉强度。原子力显微镜 (AFM) 结合变温红外光谱 (V-FTIR) 证实了 WPU 基质内存在纳米级木质素磺酸盐聚集体，并从分子间相互作用的角度讨论了增强机制。V-FTIR 进一步揭示了随着温度升高检测到的肟-氨基甲酸酯键的解离自愈的起源。这种纳米级水性分散策略在设计具有平衡自愈性能和机械性能的聚氨酯材料方面具有巨大潜力。V-FTIR 进一步揭示了随着温度升高检测到的肟-氨基甲酸酯键的解离自愈的起源。这种纳米级水性分散策略在设计具有平衡自愈性能和机械性能的聚氨酯材料方面具有巨大潜力。V-FTIR 进一步揭示了随着温度升高检测到的肟-氨基甲酸酯键的解离自愈的起源。这种纳米级水性分散策略在设计具有平衡自愈性能和机械性能的聚氨酯材料方面具有巨大潜力。