Liquid Metal-Based\nElastomer Composite with Selective\nSwitchable Adhesion to Solids

Selective switchable adhesion has recently attracted\nmuch attention\ndue to its wide applications in transfer printing, information transfer,\nand flexible electronics. However, selective adhesive materials often\nhave a complex adhesion or preparation process, which limits their\nuse. To overcome this problem, this study prepares a composite of\nliquid metal foam and polydimethylsiloxane (PDMS) with selective photocontrolled\nadhesion, which can directly adhere to solids at room temperature.\nUtilizing the photoinduced phase transition of liquid metals, solid\nadhesion can be regulated by changing the backing layer modulus of\nthe adhesive layer. Since the phase transition process is gradually\ncompleted by heat transfer from the illuminated side to the backlight\nside that adheres to the solid, the melting area on the backlight\nside can be regulated by controlling the light time, which determines\nthe adhesion regulation area. Therefore, the accuracy of the adhesion\nregulation can reach less than 0.9 mm without relying on the accuracy\nof the infrared light. Moreover, based on the selective switchable\nadhesion, the selective transfer of solids with different scales can\nbe achieved at room temperature. The findings of this study may provide\nstrategies for the simple preparation of selective adhesive materials\nand the improvement of control accuracy.