Multimodal Polymeric Crosslinker Capable of Dual Crosslinking for Enhanced Cohesion, Adhesion, and Debonding of Waterborne Acrylic Adhesives

Abstract

Waterborne acrylic adhesives, despite their widespread usage, often suffer from insufficient cohesive and adhesive properties, especially compared to solvent adhesives. Therefore, in order to improve the performance of waterborne adhesives, it is important to enhance and control these properties in a refined manner. For this purpose, herein presents a polymeric crosslinker presenting a variable number of methacrylic groups intended to control the degree of crosslinking. Polysuccinimide (PSI), which consists of a series of succinimidyl rings, is conveniently modified with methacrylic functional groups by ring-opening nucleophilic reaction to develop methacrylic PSI ("MA-PSI"). The cohesion and adhesion of MA-PSI crosslinked adhesive is comprehensively controlled by both concentration and degree of methacrylic substitution (DSMA) of MA-PSI. Moreover, the dual crosslinking, accomplished by the successive application of thermal- and photo-crosslinking, further increases the cohesion to the extent that significantly reduces the adhesion strength, which is ideal for debonding applications. Overall, the multimodal MA-PSI is a versatile crosslinker allowing broad controllability of cohesion and adhesion as well as imparting debonding capability.