Mechanochromic Photonic Vitrimer Thermal Management Device Based on Dynamic Covalent Bond

Abstract

Flexible self-healing thermal management devices are increasingly in demand due to their high flexibility, low driving voltage, and excellent stability of thermal property. In this paper, the design of mechanochromic self-healing thermal management devices is reported based on photonic vitrimer through self-healing dynamic covalent bond. A series of new photonic vitrimers i first prepared by dynamic disulfide covalent bond and PS@SiO2 photonic crystals. The resulting photonic vitrimer exhibits bright structural colors, large tensile strain (>1000%), high mechanical strength (>10 MPa) and self-healing ability (>95% efficiency). More importantly, the structural color remains constant after 10000 stretching/releasing cycles, demonstrating excellent mechanical stability, creep-resistance, and durability. Taking advantage of the above features, a novel mechanochromic flexible wireless thermal management (MFW) device is developed by semi-embedding the photonic vitrimer in a thermally conductive carbon nanotube film and then integrating it with a Bluetooth module and a control chip. Interestingly, the MFW device exhibits mechanochromic property, fast thermal response, low driving voltage (103 °C, at 3 V), and precise temperature control. Notably, the device even remains electrothermal performance (105 °C) after self-healing. This work provides new insight into the self-healing photonic materials, and the device shows promising applications in wearable electronics, vitro physiotherapy, and personal heating.