Control of diameter, morphology, and structure of PVPF nanofiber fabricated by electrospray deposition

摘要

Poly(vinylidene fluoride) (PVDF) nanofibers were prepared by electrospray deposition (ESD). To control the diameter, morphology, and structure of PVDF nanofibers, some parameters were investigated, such as polymer concentration, nozzle-to-ground collector distance, feeding rate of the polymer solution, and applied voltage. The fabricated fiber was 80-700 nm in diameter. The increase in the polymer concentration caused an increase in the polymer viscosity and fiber diameter. At low polymer concentration (5 wt %), polymer nanoparticles were formed. An increase in applied voltage will increase the fiber diameter. Variation in the nozzle-to-ground collector distance did not result in significant changes in the fiber diameter. Increase in the feeding rate of the polymer solution decreased the fiber diameter. Differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WAXD) measurements showed that the melting point and total crystallinity were decreased. Fourier transform infrared spectroscopy (FTIR) measurement revealed that ESD process induced the formation of the oriented P-phase PVDF structures. It was also demonstrated that the addition of hydrofluorocarbon solvent to polymer solution remarkably enhanced the formation of beta-phase crystalline structure of PVDF nanofiber. (c) 2006 Wiley Periodicals, Inc.