Cano Théotime, Na Hyeonuk, Sun Jeong-Yun, Kim Ho-Young
Department of Mechanical Engineering, Seoul National University, Seoul 08826, South Korea.
École des Mines de Saint-Étienne, Saint-Étienne 42100, France.
Soft Matter. 2023 Nov 22;19(45):8820-8831. doi: 10.1039/d3sm01228j.
A cross-linked polymer network immersed in a solvent will absorb molecules from its surroundings, leading to transient swelling. Under the constraint of a semi-permeable membrane, the system will swell less and generate a larger internal pressure in return, a system rarely analyzed to date. We use a nonlinear poroelastic theory to model the kinetics of swelling under mechanical constraint. We find the simulation results agree well with our experimental data using hydrogel beads made of a mixture of 3-sulfopropyl acrylate potassium salt and acrylamide, bathed in water. Understanding and predicting the response speed and the actuation stress developed during the swelling of constrained hydrogels can guide the design of polymer-based soft actuators with unusually high strength.
浸入溶剂中的交联聚合物网络会从周围环境中吸收分子，导致瞬间膨胀。在半透膜的约束下，系统的膨胀程度会减小，作为回报会产生更大的内部压力，这是一个迄今为止很少被分析的系统。我们使用非线性多孔弹性理论来模拟机械约束下的膨胀动力学。我们发现，使用由丙烯酸钾磺丙酯和丙烯酰胺的混合物制成的水凝胶珠，并将其浸泡在水中，模拟结果与我们的实验数据非常吻合。理解和预测约束水凝胶膨胀过程中的响应速度和产生的驱动应力，可以指导具有异常高强度的聚合物基软致动器的设计。
