Reworkable adhesives: Healable and fast response at ambient environment based on anthracene-based thiol-ene networks

Abstract

Fast response dismantlable and reworkable adhesives with healable and high mechanical properties are highly desirable for real-world device applications, and light-induced reworkable adhesives instead of heat-responsive systems have always been of great interest for fast speed and ambient operation. Here, anthracene-based thiol-ene networks, potentially useful as UV-induced dismantlable and reworkable adhesives, were designed and prepared via [4π+4π] cycloaddition reaction, which is active enough to be fast and efficient stimulus–response by UV-light click reaction. The synthesis and cross-linking process were tracked with infrared spectra, which confirmed successfully obtaining the target monomer and polymer networks. The extent of decrosslinking and recrosslinking were monitored by DSC and UV–vis spectroscopy, and the recovery rate of recrosslinking was up to 90%. Optical microscopy (OM) was used to observe the scratch dimensions as well as healing capability, and the results showed that the reversible cycloaddition of anthracene endowed the network with excellent self-healing properties at room temperature. And, qualitative and quantitative measurements of the mechanical properties of this reworkable adhesive showed a shear strength of up to 3.45 MPa, as well as a re-bonding recovery rate by 80%. Anthracene-based adhesives are readily fast and efficient dismantlable and reworkable, suggesting encouraging potential for degradable and re-bondable photoresists in the electronics industry and other related fields.