Building Up Debondable Adhesion with Commercial Adhesives through Surface Modification of Substrate with Vitrimers

ABSTRACT Debondable adhesion is highly attractive in the development of high-performance adhesives, particularly for sustainability initiatives requiring material recycling and reuse. Vitrimers, which possess dynamic features under specific conditions─typically at elevated temperatures─have been widely studied for the development of debondable adhesives. This work demonstrates an alternative approach to achieving debondable adhesion by establishing thin vitrimer layers on substrate surfaces via chemical modification. Poly(ethylene terephthalate) (PET) films, surface-modified with diketoenamine (DKA)-based vitrimers, were prepared to demonstrate the proposed strategy. When a commercial epoxy AB glue was utilized as the adhesive, pristine PET films did not exhibit debondable behavior. In contrast, the vitrimer-modified PET films demonstrated debonding capabilities at 50 °C, evidenced by a reduction in lap shear strength from 8.2 ± 0.9 MPa to 3.3 ± 0.9 MPa. Furthermore, acid-catalyzed hydrolysis of the DKA layers in the adhered samples resulted in a reduction in lap shear strength from 4.9 ± 0.5 MPa to 1.8 ± 0.5 MPa. This study demonstrates a highly effective approach for engineering debondable interfaces that is readily applicable to commercial adhesive systems.