A high performance wearable strain sensor with advanced thermal management for motion monitoring

TLDR

Mechanical strain in stretchable electronics generates heat that degrades performance, so rapid heat dissipation is essential. We present a stretchable strain sensor with superior thermal management. The sensor combines a thermoplastic polyurethane–boron nitride nanosheet layer for high thermal conductivity and a porous electrospun TPU membrane for insulation, achieving high stretchability, sensitivity, durability, and enabling in‑situ monitoring of temperature fluctuations during repeated stretching. The device reduces peak operating temperature by 32 %, shows no cytotoxicity, and demonstrates suitability as a next‑generation wearable sensor.

Abstract

Resistance change under mechanical stimuli arouses mass operational heat, damaging the performance, lifetime, and reliability of stretchable electronic devices, therefore rapid thermal heat dissipating is necessary. Here we report a stretchable strain sensor with outstanding thermal management. Besides a high stretchability and sensitivity testified by human motion monitoring, as well as long-term durability, an enhanced thermal conductivity from the casted thermoplastic polyurethane-boron nitride nanosheets layer helps rapid heat transmission to the environments, while the porous electrospun fibrous thermoplastic polyurethane membrane leads to thermal insulation. A 32% drop of the real time saturated temperature is achieved. For the first time we in-situ investigated the dynamic operational temperature fluctuation of stretchable electronics under repeating stretching-releasing processes. Finally, cytotoxicity test confirms that the nanofillers are tightly restricted in the nanocomposites, making it harmless to human health. All the results prove it an excellent candidate for the next-generation of wearable devices.