The effects of stretching ratio and stretching 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 ℃, enhancing temperature is good for the transition of phase α to β. By contrast, when the stretching temperature is higher than 100 ℃, enhancing temperature is unfavourable for the transition of phase α to β. Increasing the draw temperature increases the α-phase content.
