Inspired by the avoidance of toxic chemical crosslinkers and harsh reaction conditions, this work describes a poly(vinyl alcohol)‐based (PVA) double‐network (DN) hydrogel aimed at maintaining biocompatibility through the combined use of bio‐friendly additives and freezing–thawing cyclic processing for the application of synthetic soft‐polymer implants. This DN hydrogel is studied using techniques that characterize both its chemical and mechanical behavior. A variety of bio‐friendly additives are screened for their effectiveness at improving the toughness of the PVA hydrogel system in monotonic tension. Starch is selected as the best additive for further tensile testing as it brings about a near 30% increase in ultimate tensile strength and maintains ease of processing. This PVA–starch DN sample is then studied for its tensile fatigue properties through cyclic, strain‐controlled testing to develop a fatigue life curve. Though an increase in monotonic tensile strength is observed, the PVA–starch DN hydrogel does not bring about an improvement in the fatigue behavior as compared to the control. Although synthetic hydrogel reinforcement is widely researched, this work presents the first fatigue analysis of its kind and it is intended to serve as a guide for future fatigue studies of reinforced hydrogels.

中文翻译：

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含生物增韧剂的聚乙烯醇水凝胶的拉伸疲劳

受避免使用有毒化学交联剂和苛刻的反应条件启发，这项工作描述了一种基于聚乙烯醇（PVA）的双网（DN）水凝胶，旨在通过结合使用生物友好型添加剂和冷冻来保持生物相容性，用于合成软聚合物植入物的解冻循环加工。使用表征其化学和机械行为的技术研究了这种DN水凝胶。筛选了多种生物友好型添加剂，以提高单调张力下PVA水凝胶体系的韧性。淀粉被选作进一步拉伸试验的最佳添加剂，因为它可使最终抗张强度提高近30％，并且易于加工。然后通过循环应变控制测试研究这种PVA-淀粉DN样品的拉伸疲劳性能，以绘制疲劳寿命曲线。尽管观察到单调抗张强度有所增加，但与对照组相比，PVA-淀粉DN水凝胶并未带来疲劳性能的改善。尽管合成水凝胶增强材料得到了广泛的研究，但这项工作还是首次进行了疲劳分析，旨在为增强水凝胶的疲劳研究提供指导。