Preparation Of Stretchable Piezoelectric Acrylonitrile Elastomer And Its Application In Human Motion Monitoring/Wearable Devices

The human body has the characteristics of soft,stretchable,light and strong skin,and can transmit various input stimuli from the external environment?such as breeze?to the brain.Therefore,it has recently attracted many researchers to develop new materials for artificial skin,used in soft robots,wearable sensors and medical equipment and artificial intelligence equipment.Currently,piezoelectric sensors have been widely used in wearable devices to mimic the function of human skin.However,it is still a huge challenge to develop piezoelectric soft materials with high sensitivity,flexibility,high elasticity and suitable Young's modulus.The research of this topic is through the main monomers:N,N`-methylenebisacrylamide?MBA?,sodium p-styrene sulfonate?Na SS?,acrylonitrile?PAN?and polyvinylidene fluoride?PVDF?A polymer composite elastomer with good piezoelectric properties prepared after chain polymerization of several monomers and then through the freeze-drying process.Through various conventional characterizations such as scanning electron microscopy and special electrical performance characterization,we found that the dipole-dipole interaction between-C?N-chain and-CH₂/CF₂chain is used to cause the conformational change of PVDF from?conformation to?conformation),it brings with it enhanced mechanical properties.Through microscopic observations,this elastomer composed of all-organic polymers has an uneven wrinkle structure,with extremely high stretchability,super-compressibility and high elasticity.After testing with a universal electric meter,it can be found that this composite piezoelectric elastomer has excellent potential output capability(Voc_max=253 m V)and a higher piezoelectric coefficient(d_33max=63 p C/N).Experiments on finger bending,throat vibration,and pulse test verified the sensitivity,accuracy,and stability of the elastomer used as a flexible sensor.This research has made new explorations for the research and development of next-generation new wearable electronic devices.Self-powered electronic skin has been regarded by relevant researchers as a promising candidate device to solve the power consumption problem in the era of wearable medical sensors.Nowadays,research on all-organic piezoelectric sensors is still very rare.The reason is that the most commonly used organic piezoelectric material is polyvinylidene fluoride,which cannot be prepared as a film or sheet with excellent mechanical properties for the sensor.Therefore,the addition of polyvinylidene fluoride has high elasticity and high resistance.The flexible substrate can be applied to the human body or electronic equipment wearing real-time monitoring system,which provides new research ideas and methods for the research of self-powered electronic skin.