Capillary force in adhesive contact between hydrogel microspheres

The paper reports an experimental study of the adhesive contact between liquid-bridged hydrogel microparticles. A novel nanomechanical tester has been developed to measure both force-approach curves at sub-micro resolutions as well side-view images two agarose spheres during pull-off. Meanwhile, JKR theory extended quantify work adhesion solid-liquid-vapor interface and Young’s modulus particles based on measured parameters. Our research findings show is independent separation speed and, by contrast, exhibits a linear increase. also demonstrates that reconciles with generalized Hertz theory, which takes capillary force into account for soft microspheres in relationship equal twice surface tension water. These new are essential developing techniques quantitatively characterize particulate materials potentially improve material performance their applications.