Spinning elastic beads: a route for simultaneous measurements of the shear modulus and the interfacial energy of soft materials

Alessandro Carbonaro (1) , Kennedy-Nexon Chagua-Encarnacion (1) , Carole-Ann Charles (1) , Ty Phou (1) , Christian Ligoure (1) , Serge Mora (2) , Domenico Truzzolillo (1)

1 L2C - Laboratoire Charles Coulomb
2 PMMD - Physique et Mécanique des Milieux Divisés

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 polyacry-lamide 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 surface energy constant can be simultaneously deduced from their equilibrium shape. Also, our results provide further support to the scenario in which surface energy and surface tension coincide for amorphous polymer gels.

Domaines: Matière Molle [cond-mat.soft]

Alessandro Carbonaro, Kennedy-Nexon Chagua-Encarnacion, Carole-Ann Charles, Ty Phou, Christian Ligoure, et al.. Spinning elastic beads: a route for simultaneous measurements of the shear modulus and the interfacial energy of soft materials. Soft Matter, 2020, 16, pp.8412 - 8421. ⟨10.1039/d0sm01024c⟩. ⟨hal-02947316⟩