Abstract In this study, the polyacrylamide-gelatin composite hydrogels reinforced by halloysite nanotubes@polydopamine (HNTs@PDA) with NIR triggered shape memory performance and self-healing capacity were prepared through in-situ free radical polymerization of acrylamide in the mixture of Laponite-RD, HNTs@PDA and gelatin. HNTs@PDA was firstly synthesized through oxidative polymerization of dopamine on the surfaces of HNTs. HNTs@PDA was characterized by transmission electron microscopy, scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, Zeta potential, particle size analysis, and X-ray photoelectron spectroscopy. The photothermal performance of HNTs@PDA was then determined and the results reveal that HNTs@PDA can be employed as a superior photothermal agent to prepare light responsive hydrogels. The structure, morphology, mechanical properties, NIR triggered shape memory performance and self-healing capacity of the composite hydrogels were studied. The modified nanotubes act as cross-linking agent of polyacrylamide to form a rigid network in the hydrogel matrix, which leads to a significant increase in the mechanical properties. Moreover, the NIR triggered shape recovery process of the hydrogel is quite rapid, for example, it is only 63 s for recovering 720° shape change for the hydrogel of HNTs@PDA 40. The maximum NIR triggered healing efficiency of the hydrogels can reach 76%. The HNTs@PDA reinforced hydrogels with superior mechanical properties, NIR triggered shape memory, and self-healing ability exhibit promising applications in biomedical materials and smart engineering materials.

中文翻译：

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埃洛石纳米管@聚多巴胺增强聚丙烯酰胺-明胶水凝胶，具有近红外光触发形状记忆和自修复能力

摘要 本研究通过丙烯酰胺在 Laponite- 混合物中的原位自由基聚合制备了埃洛石纳米管@聚多巴胺 (HNTs@PDA) 增强的聚丙烯酰胺-明胶复合水凝胶，具有 NIR 触发形状记忆性能和自愈能力。 RD、HNTs@PDA 和明胶。HNTs@PDA 最初是通过多巴胺在 HNTs 表面的氧化聚合合成的。HNTs@PDA 通过透射电子显微镜、扫描电子显微镜、傅里叶变换红外光谱、X 射线衍射、热重分析、Zeta 电位、粒度分析和 X 射线光电子能谱进行表征。然后确定了 HNTs@PDA 的光热性能，结果表明 HNTs@PDA 可以作为一种优良的光热剂来制备光响应性水凝胶。研究了复合水凝胶的结构、形态、力学性能、近红外触发形状记忆性能和自愈能力。改性后的纳米管作为聚丙烯酰胺的交联剂，在水凝胶基质中形成刚性网络，从而显着提高机械性能。此外，水凝胶的近红外触发形状恢复过程非常迅速，例如，HNTs@PDA 40 的水凝胶恢复 720°形状变化仅需 63 s。水凝胶的最大近红外触发愈合效率可达 76 %。HNTs@PDA 增强的水凝胶具有优异的机械性能，