Electrochemical Deactivation of Switchable Catechol-Containing Smart Adhesive from Nonconductive Surfaces

The feasibility of deactivating andreactivating a catechol-containingsmart adhesive electrochemically while in direct contact with a nonconductivesurface was explored in this work. The adhesive was coated over analuminum mesh-attached poly-(dimethylsiloxane) (AM-PDMS) substrate.The aluminum mesh served as an electrode to apply electricity throughthe adhesive. A silver (Ag) counter electrode was coated in the peripheryof the adhesive-substrate interface to deactivate the adhesiveattached to the nonconductive surfaces including glass and poly-(methylmethacrylate) (PMMA) substrates. The deactivation of the adhesivewas performed with the application of up to 20 V of applied electricityutilizing the Ag electrode as a cathode and the aluminum mesh as ananode. The adhesion strength of the adhesive toward nonconductivesurfaces decreased by 98% after in situ application of electricity.The deactivation rate was tunable with the applied voltage level,exposure time to the applied voltage, surface area of the adhesiveinterface, and aluminum mesh size. The deactivated adhesive was reactivatedelectrochemically by reversing the electrode polarity up to 3 cyclesutilizing catechol-boronate complexation chemistry.

Automated summary

This study explores the feasibility of deactivating and reactivating a catechol-containing smart adhesive electrochemically while in direct contact with a nonconductive surface. The adhesive is coated over an aluminum mesh-attached poly-(dimethylsiloxane) (AM-PDMS) substrate. A silver (Ag) counter electrode is coated in the periphery of the adhesive-substrate interface to deactivate the adhesive attached to nonconductive surfaces including glass and poly-(methyl methacrylate) (PMMA) substrates. The adhesion strength of the adhesive towards nonconductive surfaces decreases by 98% after in situ application of electricity. The deactivation rate can be tuned with the applied voltage level, exposure time to the applied voltage, surface area of the adhesive interface, and aluminum mesh size. The deactivated adhesive can be electrochemically reactivated by reversing the electrode polarity up to 3 cycles using catechol-boronate complexation chemistry.