Soft, stretchable thermal protective substrates for wearable electronics

Wearable electronics have continued to attract the attention of researchers and clinicians due to their great potential in medical applications. During their operations, the undesired heating may cause thermal discomfort or damage to skin. Seeking materials and structures for advanced thermal protection has become an urgent issue. Here, we report a soft, stretchable thermal protective substrate for wearable electronics with remarkable thermal insulating performance, mechanical compliance and stretchability. The thermal protective substrate features a composite design of the widely used polymeric material polydimethylsiloxane with embedded heat absorbing microspheres, consisting of phase change materials encapsulated inside the resin shell. Experimental and numerical studies show that the thermal protective substrate could be subjected to complex deformations over 150% and could reduce the peak skin temperature increase by 82% or higher under optimizations. In vivo demonstration of this concept on the mouse skin illustrates its unusual thermal protection capability for wearable thermal management.