Study On Preparation And Properties Of Electrospun Piezoelectric Nanofibrous Membrane

Polyvinylidene fluoride?PVDF?is a kind of white powder or particle with compact molecular chain,good chemical stability,excellent mechanical properties and good film-forming property.PVDF fiber membranes prepared by electrospinning technology have the characteristics of light weight,strong signal and measurability.This excellent material can be widely used in the fields of environment,energy,sensors biomedical treatment and so on.In this paper,we used PVDF as the raw material to make the fiber membrane by electrospinning technology.The micro-morphology of the fiber membrane was observed by scanning electron microscopy?SEM?and the average diameter and distribution of the fiber were counted that helped us optimize the experimental conditions such as solvent ratio,solution concentration,working voltage,injection speed and receiving speed.Then we prepared fiber membrane with better morphology and tested the piezoelectric property and the mechanical property.The results showed that the peak voltage of the piezoelectric signal was 270 mV,and the tensile strength and elastic modulus were13 MPa and 3665 MPa.In order to improve the piezoelectric and service properties of electrospun PVDF fiber membranes,we used three inorganic substances AgNO₃,FeCl₃·6H₂O and nano-graphene to dope and modify PVDF for preparing composite fiber membranes.The morphology and crystal structure of the composite fiber membranes were analyzed by SEM and X-ray diffraction?XRD?.The piezoelectric and the mechanical properties of the fiber membranes were also tested.We studied the effect of dopants with the same amount on PVDF fiber membranes and analyzed the doping modification mechanism.The results showed:when the addition of AgNO₃ was0.3 wt%,the average diameter of the fibers was small;when the addition of FeCl3·6H2O is 0.8 wt%,the piezoelectric property improved obviously;when the addition of nanographene was 1.0 wt%,the mechanical property was good.