Comparison of Bulk- vs Layer-by-Layer-Cured Stimuli-Responsive PNIPAM–Alginate Hydrogel Dynamic Viscoelastic Property Response via Embedded Sensors
Comparison of Bulk- vs Layer-by-Layer-Cured Stimuli-Responsive PNIPAM–Alginate Hydrogel Dynamic Viscoelastic Property Response via Embedded Sensors
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DOI：
10.1021/acsapm.2c00634
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发表时间：
2022-07
影响因子：
5
通讯作者：
Yang Liu;Keturah Bethel;Manjot Singh;Junru Zhang;R. Ashkar;E. Davis;Blake N. Johnson
中科院分区：
文献类型：
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作者：
Yang Liu;Keturah Bethel;Manjot Singh;Junru Zhang;R. Ashkar;E. Davis;Blake N. Johnson
虽然刺激响应型水凝胶目前正被广泛研究，例如用于增材制造应用，但使用传统表征方法持续监测其材料特性对刺激的动态响应仍然是一个挑战。在这里，我们报告了动态模式压电微悬臂传感器能够实时监测块体和逐层（LBL）固化复合聚（n -异丙基丙烯酰胺）(PNIPAM) -海藻酸盐水凝胶结构在25-37℃温度范围内的热变化的粘弹性响应。扫描电镜和传感研究表明，离子-共价纠缠复合pnipam -海藻酸盐水凝胶结构的网络结构和粘弹性响应取决于水凝胶的加工方法。与体固化结构相比，LBL固化制备的pnipam -海藻酸盐复合结构在热刺激驱动的剪切储存模量变化幅度方面表现出相对更高的响应性，这表明增材制造应用的机会。总之，我们表明，传感器与传统表征方法相结合，可以研究刺激响应软材料的动态过程-结构-流变特性关系，并使用低样本量测量格式实时监测材料流变特性。
While stimuli-responsive hydrogels are now being widely investigated, such as for additive manufacturing applications, it remains a challenge to continuously monitor the dynamic response of their material properties to stimuli using traditional characterization methods. Here, we report that dynamic-mode piezoelectric milli-cantilever sensors enable real-time monitoring of the viscoelastic response of bulk- and layer-by-layer (LBL)-cured composite poly(N-isopropylacrylamide) (PNIPAM)–alginate hydrogel constructs to thermal changes across the 25–37 °C temperature range. Scanning electron microscopy and sensing studies revealed that the network structure and viscoelastic response of ionic–covalent entanglement composite PNIPAM–alginate hydrogel constructs are dependent on the hydrogel processing method. Composite PNIPAM–alginate constructs fabricated using LBL curing exhibited relatively increased responsiveness compared to bulk-cured constructs in terms of the magnitude of thermal stimulus-driven shear storage modulus change, suggesting opportunities for additive manufacturing applications. In summary, we show that sensors, in combination with traditional characterization methods, enable the study of dynamic process–structure–rheological property relations of stimuli-responsive soft materials and real-time monitoring of material rheological properties using a low-sample volume measurement format.