Dielectric properties of electrospun titanium compound/polymer composite nanofibres

Poly(vinylpyrrolidone)/tetrabutyl titanate (PVP/ CH₃(CH₂)₃O₄Ti) composite nanofibres are prepared by electrospinning. After calcining parts of composite nanofibres in air at 700 ℃, petal-like TiO₂ nanostructures are obtained. The characterizations of composite nanofibres and TiO₂ nanostructures are carried out by a scanning electron microscope, an x-ray diffractometer, and an infrared spectrometer. Electrospun nanofibres are pressed into pellets under different pressures in order to explore their dielectric properties. It is found that the dielectric constants decrease with frequency increasing. The dielectric constant of the composite nanofibre pellet increases whereas its dielectric loss tangent decreases due to the doped titanium ions compared with those of pure PVP nanofibre pellets. In addition, it is observed that the dielectric constant of the composite nanofibre pellet decreases with the increase of the pressure applied in pelletization.