Stretchable and recoverable acrylate-based pressure sensitive adhesives with high adhesion performance, optical clarity, and metal corrosion resistance

Abstract

In the era of the Internet of Things, digital displays play a critical role in human-machine interfaces. In particular, displays applied to contemporary devices such as flexible smart watches and foldable/rollable electronics underline the need for pertinent materials and device technologies to fulfill their designed functions. However, despite the technical advancements of electronic components such as stretchable/flexible electrodes and flexible backplanes, their proper assembly remains a challenge. Herein, we report the compositional effect of acrylic acid (AA) on the physical properties of as-synthesized pressure sensitive adhesives (PSAs), especially on their adhesion performance in terms of wettability and peel adhesion. Accordingly, an empirical criterion for intimate wetting is proposed based on the storage modulus of the PSAs. In this study, the PSA with the best adhesion performance was evaluated for its viscoelastic properties and suitability for specific applications. The results demonstrated the strain-dependent conformational recovery of the adhesive; the implementation of the prestrain strategy enables rapid strain reversibility at 25% of the total strain. Furthermore, the AA-incorporated PSAs exhibited remarkable metal corrosion resistance as well as high optical clarity. Thus, this fundamental study of stretchable PSAs can provide useful guidance for the development of advanced PSAs that can be used in a wide range of applications involving display devices.