Three-dimensional infrared absorption of hot-drawn and poled electro-optic PVDF films

Oriented poly(vinylidene fluoride) (PVDF) films prepared by hot-drawing and poling treatments were examined by three-dimensional Fourier transform infrared spectroscopy. This technique clearly shows that the dipoles distribution of samples were oriented in the drawing direction and then in the electric-field direction after poling. By this technique, the β phase fractions of the PVDF film contributed by the drawing and the poling processes in three principal axis directions can be individually calculated and then the total β phase fraction can be obtained. The sample film after drawing and poling has a highly oriented β phase, and a large electro-optic coefficient r33 of 0.27 pm V−1 was measured.