Research on the Electrospinning Processed Highly Aligned P(VDF-TrFE) and Related Composite Film Applications

Using the electrospinning process to fabricate highly aligned arrays of nanofibers of poly(vinylidenefluoride-co-trifluoroethylene) (P(VDF-TrFE)(75/25) were the main research topic in this thesis and we found the optimal parameters of electrospinning process to fabricate the highly aligned membrane. (P(VDF-TrFE) was a ferroelectric material and having several advantages, such as good chemical stability, high sensitivity, biocompatibility and strong piezoelectricity. Because of the above-mentioned advantages, (P(VDF-TrFE) membrane was suitable for the development of flexible sensors. After electrospinning process, (P(VDF-TrFE) nanofiber was aligned to become highly aligned membrane and it provided (P(VDF-TrFE) with more β phase, i.e., with higher piezoelectric performance. Furthermore, we used annealing and corona poling processes to enhance the piezoelectricity of (P(VDF-TrFE). In this thesis, we measured the hysteresis loop of (P(VDF-TrFE) membrane to determine its ferroelectricity. We also used X-ray diffraction (XRD) and scanning electron microscope(SEM) to observe its crystallization and surface structure. Although P(VDF-TrFE) was identified to have improved mechanical properties along the fiber axial orientation after electrospinning and annealing process, it was found to be weak along the lateral axis. To alleviate this problem, we coated polydimethylsiloxane (PDMS) on the membrane to enhance its mechanical properties, water resistant and promote potential on application of flexible sensor.