Self-healing hydrogels with intrinsic self-healing ability, injectability, and biocompatibility have good potential in biomedical applications. The relevance between the self-healing ability and inner structure of hydrogels, however, has rarely been examined. The design criteria of self-healing hydrogels remain to be established. In this study, we utilized in situ small-angle X-ray scattering (in situ SAXS) and coherent X-ray scattering (CXS) to analyze the dynamics and gelation mechanism of three types of chitosan-based self-healing hydrogels with different dynamic interactions. In situ SAXS revealed the nucleation and growth mechanism for the gelling process, which has not been reported in a system of self-healing hydrogels. The critical nucleation radius (CNR) with different interactions could further influence the gelation rate and self-healing ability. Moreover, the continuous time-resolved CXS profile unveiled the dynamic behavior of different self-healing hydrogels in mesoscale, supported by rheological experiments. Information linking the rheological properties and structural changes could be useful in designing self-healing hydrogels for biomedical applications.

中文翻译：

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原位 SAXS 和相干 X 射线散射壳聚糖自愈水凝胶的凝胶机制和结构动力学

具有内在自愈能力、可注射性和生物相容性的自愈水凝胶在生物医学应用中具有良好的潜力。然而，很少有人研究水凝胶的自愈能力和内部结构之间的相关性。自愈水凝胶的设计标准仍有待确定。在本研究中，我们利用原位小角度 X 射线散射（原位 SAXS）和相干 X 射线散射（CXS）分析了三种不同动力学的壳聚糖基自愈水凝胶的动力学和凝胶机制。互动。原位 SAXS 揭示了胶凝过程的成核和生长机制，这在自愈水凝胶系统中尚未见报道。具有不同相互作用的临界成核半径（CNR）会进一步影响凝胶速率和自愈能力。此外，连续时间分辨的 CXS 曲线揭示了不同自修复水凝胶在中尺度中的动态行为，并得到流变实验的支持。将流变特性和结构变化联系起来的信息可用于设计用于生物医学应用的自愈水凝胶。