Abstract Ecoflex, a commercially available silicone polymer, has attracted considerable attention due to its wide range of applications. The polymer has various Shore hardnesses that represent its wide range of stiffnesses. In this contribution, we have conducted a plethora of experiments under the uniaxial mode of tensile deformation. These experiments consist of loading-unloading cyclic tests, stretchability tests, single-step relaxation tests, Mullins effect tests, stress recovery tests, and temperature-dependence tests at different strain levels. All tests are revisited with Ecoflex of five Shore hardnesses ranging from Shore 00–10 to Shore 00–50. Extensive experimental findings illustrate that the material consists of an equilibrium stress part and an overstress part. Constitutive frameworks with an amplified strain invariant are proposed to predict the mechanical responses of Ecoflex over a wide range of Shore hardnesses. Afterwards, the frameworks are extended to capture the stress softening behaviour significantly observed in the material. Relevant examples illustrate that proposed constitutive models accurately predict stress-strain responses and the stress softening behaviour of Ecoflex. The current experimental study will work as a guide in selecting Ecoflex with an appropriate Shore hardness for applications in stretch sensors, soft robotics, and energy harvesters. Moreover, the novel concept of Shore-dependent modelling proposed herein can be applied to predict the stress-strain behaviour of other soft polymers appearing with various Shore hardnesses where there exist difficulties in obtaining experimental data of a particular Shore hardness.

中文翻译：

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不同肖氏硬度的 Ecoflex 聚合物：实验研究和本构建模

摘要 Ecoflex 是一种市售的有机硅聚合物，由于其广泛的应用而引起了广泛的关注。该聚合物具有代表其广泛刚度范围的各种肖氏硬度。在这个贡献中，我们在单轴拉伸变形模式下进行了大量实验。这些实验包括不同应变水平下的加载-卸载循环测试、拉伸性测试、单步松弛测试、穆林斯效应测试、应力恢复测试和温度依赖性测试。所有测试都使用 Ecoflex 重新审视，具有五种肖氏硬度，范围从肖氏 00-10 到肖氏 00-50。大量的实验结果表明，该材料由平衡应力部分和过应力部分组成。提出了具有放大应变不变量的本构框架来预测 Ecoflex 在广泛的肖氏硬度范围内的机械响应。然后，扩展框架以捕捉在材料中显着观察到的应力软化行为。相关示例表明，提议的本构模型准确预测了 Ecoflex 的应力应变响应和应力软化行为。当前的实验研究将作为选择具有适当肖氏硬度的 Ecoflex 的指南，用于拉伸传感器、软机器人和能量收集器的应用。而且，