Large deformations of soft elastic beads spinning at high angular velocity in a denser background fluid are investigated theoretically, numerically, and experimentally using millimeter-size polyacrylamide hydrogel particles introduced in a spinning drop tensiometer. We determine the equilibrium shapes of the beads from the competition between the centrifugal force and the restoring elastic and surface forces. Considering the beads as neo-Hookean up to large deformations, we show that their elastic modulus and interfacial energy constant can be simultaneously deduced from their equilibrium shape. Also, our results provide further support to the scenario in which interfacial energy and interfacial tension coincide for amorphous polymer gels.

中文翻译：

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旋转弹性珠：一种同时测量软材料的剪切模量和界面能的途径。

使用引入纺丝液滴张力计的毫米尺寸聚丙烯酰胺水凝胶颗粒，在理论上，数值上和实验上研究了在较高的背景流体中以高角速度旋转的软弹性珠的大变形。我们通过离心力与恢复弹性力和表面力之间的竞争来确定珠粒的平衡形状。考虑到小变形之前的珠子都是新胡克星，我们表明它们的弹性模量和界面能常数可以同时从它们的平衡形状中推导出来。同样，我们的结果为无定形聚合物凝胶的界面能和界面张力一致的情况提供了进一步的支持。