Ficarella Elisa, Minooei Mohammad, Santoro Lorenzo, Toma Elisabetta, Trentadue Bartolomeo, De Spirito Marco, Papi Massimiliano, Pruncu Catalin I, Lamberti Luciano
Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, 70125 Bari, Italy.
Istituto di Fisica, Università Cattolica del S. Cuore, 00168 Roma, Italy.
Materials (Basel). 2021 Mar 5;14(5):1223. doi: 10.3390/ma14051223.
This article presents a very detailed study on the mechanical characterization of a highly nonlinear material, the immature equine zona pellucida (ZP) membrane. The ZP is modeled as a visco-hyperelastic soft matter. The Arruda-Boyce constitutive equation and the two-term Prony series are identified as the most suitable models for describing the hyperelastic and viscous components, respectively, of the ZP's mechanical response. Material properties are identified via inverse analysis based on nonlinear optimization which fits nanoindentation curves recorded at different rates. The suitability of the proposed approach is fully demonstrated by the very good agreement between AFM data and numerically reconstructed force-indentation curves. A critical comparison of mechanical behavior of two immature ZP membranes (i.e., equine and porcine ZPs) is also carried out considering the information on the structure of these materials available from electron microscopy investigations documented in the literature.
本文对一种高度非线性材料——未成熟马透明带（ZP）膜的力学特性进行了非常详细的研究。ZP被建模为粘弹性超软物质。分别确定Arruda-Boyce本构方程和双项Prony级数为描述ZP力学响应的超弹性和粘性成分的最合适模型。通过基于非线性优化的反分析来确定材料特性，该反分析拟合了在不同速率下记录的纳米压痕曲线。原子力显微镜（AFM）数据与数值重建的力-压痕曲线之间的良好一致性充分证明了所提方法的适用性。还考虑了文献中电子显微镜研究提供的关于这些材料结构的信息，对两种未成熟ZP膜（即马ZP和猪ZP）的力学行为进行了关键比较。
