The Research Of Self-Healing Photonic Skin Based On Cholesteric Liquid Crystal Elastomers

In the age of information,digitization and intelligence,the demand for flexible and soft electronic equipment is growing.In particular,portable,highly sensitive and multi-functional flexible wearable electronic devices have attracted much attention in the fields of personalized health monitoring,human motion detection,man-machine interface and soft robots.Because of its excellent optical signal display,color-changing skin has enriched the functional diversity of electronic skin,so the research heat is increasing in recent years.Cholesteric liquid crystal elastomer(CLCE)is a kind of polymer material which can change the physical or chemical characteristics in response to external stimuli.It has a sensitive mechanical discoloration response,which presents a unique advantage as the optical coordination primitive of electronic skin devices.Triboelectric nanogenerator(TENG)relies on the triboelectrification and contact electrification principles to effectively collect and convert energy from various forms,including human movement,walking,vibration,mechanical departure and wind energy,into electric energy.The main purpose of this project is to prepare a composite photon film with sensitive mechanical discoloration response,design and construct photon skin with photoelectric cooperative signal output,and finally explore its potential application in the field of monitoring human movement.The research content includes the following two aspects:1.Photonic skin based on CLCE with non-polymerizable liquid crystalA photonoc skin with mechanical discoloration response and stable electrical output was designed and constructed.Firstly,cholesteric liquid crystal polymer films with specific reflection wavelength were prepared,and the non-polymerizable small molecule 5CB was introduced into the system to increase the flexibility of liquid crystal polymer.Then,based on the mechanism of dynamic imine bond,transparent self-healing polydimethylsiloxane(PDMS)film with excellent tensile properties was prepared.Metal Al sheet was used as an electrode to form a multilayer structure with the above materials,and a multifunctional electronic skin with light and electrical output was designed and prepared,which provided a strategic basis for the design of photonic skin with better performance in subsequent studies.2.Photonic skin of based on CLCE with thiol chain expansion reactionPhotonic skin with photoelectric cooperative signal output is designed and constructed,and its application in human motion monitoring is studied.Firstly,CLCE with excellent mechanical color-changing response was prepared by anisotropic antiswelling method based on the click chemical reaction of mercaptan acrylate and UV polymerization.The self-healing PDMS were also used as the friction layer of TENG,and then the electrode was optimized into more transparent silver nanowires(Ag NWs).Design and manufacture wearable electronic devices.The introduction of Ag NWs also provides excellent and stable electrical output for the photon skin without affecting the precursor of the photonic band gap change caused by CLCE stretching.The photonic skin with the collaborative output of photoelectric dual signals can be used to monitor human movement,which provides a new idea for the multi-functional selection of wearable electronic devices.