Background Little is known about the effect of water content on the mechanical properties of dual cross-linked hydrogels. Objective To quantify the changes in the mechanical response and equilibrium modulus in a PVA hydrogel as a function of the hydration level. Methods A dual cross-linked hydrogel was tested in tension to a stretch of 1.3 at two stretch rates and in a stress relaxation test. The equilibrium modulus was calculated using the final relaxation stress value. Results The stiffness of the hydrogel increases significantly as the gel dries. Conclusions The equilibrium modulus is found to be linear with the hydration level and approximately 2 × stiffer at 60% hydration relative to 90%.

中文翻译：

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水合作用对双交联 PVA 水凝胶拉伸响应的影响

背景 关于水含量对双交联水凝胶机械性能的影响知之甚少。目的量化 PVA 水凝胶中机械响应和平衡模量的变化，作为水合水平的函数。方法 在两种拉伸速率和应力松弛测试中测试双交联水凝胶拉伸至 1.3 倍。使用最终松弛应力值计算平衡模量。结果随着凝胶干燥，水凝胶的刚度显着增加。结论 平衡模量被发现与水化水平呈线性关系，并且在 60% 的水化率相对于 90% 的水化率高约 2 倍。