Preparation Of Multidimensional Electrospun Fibers And Construction Of Stretchable Electronic Devices

Flexible and stretchable conductors with both high tensile and high conductivity play a crucial role in high-performance flexible electronic devices.However,there are still some challenges to achieve stable and good electrical conductivity under large strains.Based on this background,six multidimensional electrospun fibers with different properties are prepared by electrospinning method and mechanical twisting.After studying their structures and properties,the polyvinylidene fluoride-hexafluoropropylene(PVDF-HFP)with better performance is selected as the substrate,and a multidimensional Ag NWs/PVDF-HFP helical fibrous conductor is prepared by dip-coating a conductive layer of silver nanowires(Ag NWs)on it.The multidimensional Ag NWs/PVDF-HFP helical fibers are found to be highly stretchable-highly conductive with antibacterial and environmental stability.Finally,their potential applications as stretchable conductors,strain sensors and antenna are explored.The specific research contents and results are as follows:1.Preparation of multidimensional electrospun fibers and characterization of their structures and properties.Firstly,six electrospun fibrous membranes are prepared by electrospinning technology,and the corresponding six multidimensional electrospun fibers with micro nano scale to macro helical structure scale are obtained by mechanical twisting.Then their microscopic morphology,wetting properties and mechanical properties are comparatively analyzed.It is found that changing the structure of the fibrous membranes by mechanical twisting can effectively regulate its wetting and mechanical properties.2.Select PVDF-HFP with strong spinnability and excellent performance as the substrate,and explore the structural properties and mechanism of multi-dimensional Ag NWs/PVDF-HFP helical fibers.The dynamic evolution mechanism and inter-mapping relationship of the structure and properties of multidimensional Ag NWs/PVDF-HFP helical fibers during the stretching process are illustrated,as well as the analytical characterization of antimicrobial properties and environmental stability resistance.It is found that the multidimensional Ag NWs/PVDF-HFP helical fibers have a multi-scale structure at the microscopic and macroscopic levels as well as possess high tensile-high electrical conductivity(271665 S/m at 1153% stretch)and antibacterial and environmental stability.3.Device applications of multidimensional Ag NWs/PVDF-HFP helical fibers.Multi-dimensional Ag NWs/PVDF-HFP helical fibers can be used as stretchable flexible wires to connect closed circuits at 800% high strain;multi-dimensional Ag NWs/PVDF-HFP helical fibers can be used as serial connection wires for microcontrollers to realize circuit conduction functions.The multidimensional Ag NWs/PVDF-HFP helical fibers can be used as flexible strain sensors directly attached to human joints to monitor joint motion.The multidimensional helical structure of Ag NWs/PVDF-HFP fibers can be used as antenna components of narrowband Io T modules to realize electromagnetic wave transmission and reception under mechanical stretching and harsh weather conditions.