Cook-Chennault Kimberly, Anaokar Sharmad, Medina Vázquez Alejandra M, Chennault Mizan
Mechanical and Aerospace Engineering Department, Rutgers University, Piscataway, NJ 08854-5750, USA.
Biomedical Engineering Department, Rutgers University, Piscataway, NJ 08554-5750, USA.
Polymers (Basel). 2024 Jun 25;16(13):1797. doi: 10.3390/polym16131797.
Hydrogels have been extensively studied for biomedical applications such as drug delivery, tissue-engineered scaffolds, and biosensors. There is a gap in the literature pertaining to the mechanical properties of hydrogel materials subjected to high-strain dynamic-loading conditions even though empirical data of this type are needed to advance the design of innovative biomedical designs and inform numerical models. For this work, HEMA-DMAEMA hydrogels are fabricated using a photopolymerization approach. Hydrogels are subjected to high-compression oscillatory dynamic mechanical loading at strain rates equal to 50%, 60%, and 70%, and storage and loss moduli are observed over time, e.g., 72 h and 5, 10, and 15 days. As expected, the increased strains resulted in lower storage and loss moduli, which could be attributed to a breakdown in the hydrogel network attributed to several mechanisms, e.g., increased network disruption, chain scission or slippage, and partial plastic deformation. This study helps to advance our understanding of hydrogels subjected to high strain rates to understand their viscoelastic behavior, i.e., strain rate sensitivity, energy dissipation mechanisms, and deformation kinetics, which are needed for the accurate modeling and prediction of hydrogel behavior in real-world applications.
水凝胶已被广泛研究用于生物医学应用，如药物递送、组织工程支架和生物传感器。尽管推进创新生物医学设计的设计并为数值模型提供信息需要此类经验数据，但关于承受高应变动态加载条件的水凝胶材料的机械性能，文献中仍存在空白。在这项工作中，采用光聚合方法制备了甲基丙烯酸羟乙酯-甲基丙烯酸二甲氨基乙酯（HEMA-DMAEMA）水凝胶。使水凝胶在应变速率分别为50%、60%和70%的条件下承受高压缩振荡动态机械加载，并随时间观察储能模量和损耗模量，例如72小时以及5天、10天和15天。正如预期的那样，应变增加导致储能模量和损耗模量降低，这可能归因于水凝胶网络因多种机制而破裂，例如网络破坏增加、链断裂或链滑移以及部分塑性变形。这项研究有助于增进我们对承受高应变速率的水凝胶的理解，以了解它们的粘弹性行为，即应变速率敏感性、能量耗散机制和变形动力学，这些对于在实际应用中准确建模和预测水凝胶行为是必需的。
