Heat-induced spontaneous and damage-free separation of transparent polymer thin films based on clickable decomposition of pyrolytic core-shell nanocapsules

Abstract

The automatic and damage-free manipulation for efficient separation of polymer thin films from various substrates has received growing interests in a broad range of applications from electronic devices to optical films because it can realize the innovative recycling and on-demand spontaneous detachment of scarce and valuable materials. Herein, we demonstrate a spontaneous and damage-free separation methodology for transparent polymer thin films based on the heat-induced microbubble generation from pyrolytic core-shell nanocapsules at the interface between the substrate and the thin film. The pyrolytic polymer nanocapsules were fabricated by encapsulating a latent gas-forming agent of benzenesulfonyl hydrazine in the crosslinked copolymer nanoparticle comprising polyacrylonitrile and poly(methyl methacrylate). The heat-induced clickable decomposition of pyrolytic core-shell nanocapsules generated a significant number of microbubbles inside the thin film, thereby inducing instantaneous and effortless detachment of the transparent film from substrate. The fabricated polymer thin films embedded with a small number of pyrolytic polymer nanocapsules afforded an excellent debonding performance with a maximum efficiency of 93.4% after short thermal treatment compared to that of the pristine thin films, simultaneously maintaining a remarkable optical clarity of about 99% and a high initial adhesion strength with a maximum of approximately 22 kgf cm−2.