Preparation And Sensing Properties Study Of Degradable Elastomer/2D Nanocomposite

Flexible wearable electronic sensors have attracted tremendous attention due to their potential application in human motion detection and healthcare monitoring With the development of science and technology and the improved social living standards,the demand for electronics is also increasing.Traditional electronic devices are prone to produce various toxic substances to pollute the environment during the complex manufacturing process and the slow degradation process after discarding,therefore,it is of great significance to prepare environmental friendly and degradable polymer-based flexible electronic devices to reduce electronic waste and protect the environment.This study aims to prepare flexible wearable electronic sensors with excellent sensing performance and friendly degradability by developing degradable polymer substrate and rationally designing the sensing structure,which can be used for portable human motion detection and disease diagnosis.1.The sensing layer was prepared by spreading MXene layer onto the copolymer of poly(1,8-octanediol-citric acid)and polycaprolactone(POC-PCL)film with microspinous structure,which can greatly improve the sensing sensitivity.The flexible biodegradable pressure sensor was obtained by assembling the conductive sensing layer with a POC-PCL film patterned interdigitated electrode face to face.It is the rough microspinous structure and the interdigitated electrode that endow the sensor high sensitivity and wide sensing range.The effect of the roughness of the microspinous structure and the load content of MXene to the sensing performance was experimentally studied.The obtained sensor exhibits extremely high sensitivity(1527.80 kPa-1),wide sensing range(up to 125 kPa),ultra-low detection limit(2 Pa),fast response/recovery time(8 ms/8 ms),excellent cycle stability and good degradability.The sensor can be also used for real-time detection of human subtle physiological signals(such as pulse,chewing)and large-scale muscle movements.In addition,the array-type electronic skins were successfully assembled to realize large-area spatial pressure distribution monitoring,and it can also be coupled with a wireless transmitter to realize wirelessly real-time monitoring.2.In this work,we fabricated a flexible and highly sensitive NH3 sensor via in-situ polymerizations of aniline(ANI)and reduced graphene oxide(rGO)on a degradable PCL-TPU film.The sensor possesses extremely low detection limit to ammonia gas(100 ppb),high sensitivity,and excellent ammonia selectivity at room temperature,which is promising to be used for human healthcare monitoring by detecting the characteristic disease gas exhaled by human.What's more,the sensor not only exhibits stable sensing performance in different humidity environments(RH?14%-37%),but also possesses reliable and robust degradability in solvents,which paves the way for the preparation of environmentally friendly and degradable flexible ammonia sensors.