Reprocessable thermoset organosilicon elastomer with good self-healable and high stretchable properties for flexible electronic devices

Abstract

Manufacturing organosilicon elastomers that have combined reprocessability, self-healing, and high stretchable properties, this remains a significant challenge. Herein, we proposed a simple one-pot method to synthesize thermoset organosilicon elastomers which could be self-healed and had good mechanical properties. The elastomers were capped with the α,ω-hydroxypolydimethylsiloxane and isophorone diisocyanate, following chain expansion with adipic dihydrazide, and cross-linked by triethanolamine. The average elongation of the elastomers was 1145%, with the largest strain of 4.1 MPa. Due to the highly flexible Si-O chain and the large number of hydrogen bonds formed by the dynamic acyl semicarbazide (ASC) groups, the elastomers had good self-healing ability. It was noted that the elastomers could be recycled entirely under the synergistic dynamic effect of ASC groups without chemical treatment, and the elastomers could achieve 91% of the initial mechanical strength even after ten times of dissolution recycling. And through three times of hot pressing recovery, 86% of the mechanical properties were also maintained. In addition, the self-healing flexible electronic devices were prepared by compounding multi-walled carbon nanotubes (MWCNTs), and they could monitor the subtle movements of the human body. This work fabricated the reprocessable and self-healing organosilicon elastomers for flexible electronic devices, which might have essential inspiration for the sustainable development of organosilicon materials.