A strong and reversible adhesive fibrillar surface based on an advanced composite with high strength and strong adhesion

ABSTRACT A material-structure integrated design method is proposed in this paper, with which micropillar and microwedge arrayed surfaces are fabricated based on a novel nanoparticle-reinforced silicone rubber composite (NRSRC) with high mechanical strength and strong surface adhesion. It is found that the micropillar-arrayed surface and the microwedge-arrayed surface show a normal adhesive strength of 50.9 kPa and a shear adhesive strength of 137.3 kPa, respectively, which are much higher than those of previously reported adhesive surfaces made by pure soft polymers. Furthermore, the microwedge-arrayed surface shows not only strong and stable adhesion on rough and smooth substrates but also an obvious anisotropy in the adhesion property. The latter consequently leads to an easy control of the attachment/detachment switch, which is evidenced by a mechanical gripper with a microwedged surface. Therefore, firmly picking up and easily releasing a heavy glass plate can be realized. All these results demonstrate the apparent advantages of the present composite-based fibrillar surfaces in achieving reliable and reversible adhesion and should have promising applications for manufacturing advanced adhesive devices, such as mechanical fixtures, portable climbing equipment and space robots. Graphical Abstract