Poly(vinyl alcohol) (PVA) hydrogels are water-rich, three-dimensional (3D) network materials that are similar to the tissue structure of living organisms. This feature gives hydrogels a wide range of potential applications, including drug delivery systems, articular cartilage regeneration, and tissue engineering. Due to the large amount of water contained in hydrogels, achieving hydrogels with comprehensive properties remains a major challenge, especially for isotropic hydrogels. This study innovatively prepares a multiscale-reinforced PVA hydrogel from molecular-level coupling to nanoscale enhancement by chemically cross-linking poly(vinylpyrrolidone) (PVP) and in situ assembled aromatic polyamide nanofibers (ANFs). The optimized ANFs–PVA–PVP (APP) hydrogels have a tensile strength of ≈9.7 MPa, an elongation at break of ≈585%, a toughness of ≈31.84 MJ/m³, a compressive strength of ≈10.6 MPa, and a high-water content of ≈80%. It is excellent among all reported PVA hydrogels and even comparable to some anisotropic hydrogels. System characterizations show that those performances are attributed to the particular multiscale load-bearing structure and multiple interactions between ANFs and PVA. Moreover, APP hydrogels exhibit excellent biocompatibility and a low friction coefficient (≈0.4). These valuable performances pave the way for broad potential in many advanced applications such as biological tissue replacement, flexible wearable devices, electronic skin, and in vivo sensors.

中文翻译：

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芳纶纳米纤维增强的强韧、生物相容性聚（乙烯醇）-聚（乙烯基吡咯烷酮）多尺度网络水凝胶

聚乙烯醇（PVA）水凝胶是富含水的三维（3D）网络材料，与生物体的组织结构相似。这一特性赋予水凝胶广泛的潜在应用，包括药物输送系统、关节软骨再生和组织工程。由于水凝胶中含有大量的水，获得具有综合性能的水凝胶仍然是一个重大挑战，特别是对于各向同性水凝胶。本研究通过化学交联聚（乙烯基吡咯烷酮）（PVP）和原位组装芳香族聚酰胺纳米纤维（ANF）创新性地制备了从分子级偶联到纳米级增强的多尺度增强PVA水凝胶。优化后的ANFs-PVA-PVP（APP）水凝胶的拉伸强度约为9.7 MPa，断裂伸长率约为585%，韧性约为31.84 MJ/m ³，压缩强度约为10.6 MPa，并且具有较高的耐压强度。 -含水量约80%。它在所有报道的 PVA 水凝胶中表现优异，甚至可以与一些各向异性水凝胶相媲美。系统特性表明，这些性能归因于特定的多尺度承载结构以及 ANF 和 PVA 之间的多重相互作用。此外，APP水凝胶表现出优异的生物相容性和低摩擦系数（约0.4）。这些宝贵的性能为生物组织替代、柔性可穿戴设备、电子皮肤和体内传感器等许多先进应用的广泛潜力铺平了道路。