Conductive Elastomer Composites With Microdome Structure For Wearable Pressure Sensing And Thermal Management

Recently,with the increasing demand for human health monitoring,great progress has been made on the wearable electronic devices.The pressure sensor,as an important part of the flexible electronic devices,has drawn considerable research interest.However,most of pressure sensors could not possess wide detection range and high sensitivity.Meanwhile,traditional pressure sensors are lack of efficient thermal management capability to satisfy the thermal comfort in human skins.Herein,we develop the thermoplastic polyurethane/boron nitride nanosheets/MXene（TPU/BNNS/MXene）composites with excellent sensing performance and advanced thermal management function,which can be employed to diagnose and treat the disease,such as tenosynovitis.（1）The polystyrene（PS）microspheres were assembled onto the polydimethylsiloxane（PDMS）substrate as the microsphere arrays,which was employed to prepare the reusable templates with the regular and uniform microsphere structure.Subsequently,thermoplastic polyurethane/boron nitride nanosheets（TPU/BNNS）composites with the microdome structure were prepared by the template method.Finally,TPU/BNNS/MXene composites were prepared by coating the TPU/BNNS composites with MXene.（2）The wearable TPU/BNNS/MXene pressure sensor was obtained by combining the TPU/BNNS/MXene composite with microdome structure and a TPU/BNNS film coated with an interdigitated electrode.The obtained sensor exhibited a high sensing sensitivity due to the rapid change of contact area between the microdome structure and the interdigitated electrode during compression.The sensor exhibited excellent sensing performance(excellent cycling stability:～20000 cycles;high sensitivity in a wide working range:288.95 k Pa^-1 for 50 Pa-5 k Pa;42.38 k Pa^-1 for 5 k Pa-～50 k Pa;8.41 k Pa^-1 for～50 k Pa-300 k Pa).Subsequently,it could monitor human motions at different scales（such as finger bending,pulse,and so on）.（3）The TPU/BNNS/MXene composite possessed advanced thermal management function and photothermal therapy capability to tenosynovitis.Owing to the thermally conductive network of BNNS,the TPU/BNNS composite possessed a high thermal conductivity（0.405 W/（m·K））at 15 wt%loading of BNNS,which can dissipate the heat in time and satisfy the thermal comfort.In addition,due to the good photothermal effect of MXene,the TPU/BNNS/MXene composite could be employed as the wearable heater with outstanding photothermal capability(reaching 51℃within 100 s at the NIR light power density of 0.50 W/cm^-2).Moreover,the TPU/BNNS/MXene sensor could monitor the wrist bending and diagnose the tenosynovitis.What’s more,due to the good photothermal performance of the TPU/BNNS/MXene composite,the composite could be attached to the wrist for photothermal heating,which could promote the blood flow and reduce the pain of the wrist.Therefore,the TPU/BNNS/MXene composite possessed a good thermal management function and could be used to diagnose and treat the tenosynovitis.