Effects of Stretching ratio and temperature on phase transition of melt-spun poly (vinylidence Fluoride) fibers

Abstract

The effects of stretching ratio and stetching temperature on phase transition of melt-spun poly (vinylidene fluoride) fibers were investigated and analyzed by using scanning electron microscopy, wide angle X-ray diffraction, differential scanning calorimetry and Fourier transfer infrared spectroscopy. The β phase exists in the as-spun fiber. The β phase content increases as the stretching ratio increases. When the stretching temperature is lower than 100°C, enhancing temperature is good for the transition of phase α to β. By contrast, when the stretching temperature is higher than 100°C, enhancing temperature is unfavourable for the transition of phase α to β. Increasing the draw temperature increases the α-phase content

Keywords

poly (vinylidene fluoride) / melt-spun / β-phase crystal / α-phase crystal

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