Synthesis and Electrooptic Properties of a New Chromophore Dispersed or Grafted in a Carbazolyl Methacrylate Matrix

A copolymer of [11-(N-carbazolyl)undecyl methacrylate] and ethyl (E)-2-cyano-3[5-(5-(4-methacryloyloxy)piperidino-2-thienylcarbonyl)-2-thienyl]- 2-propenoate has been prepared. The photoconductivity and the electrooptic properties of a hot-pressed thin film of this copolymer have been measured and compared with the properties of the dispersion of ethyl (E)-2-cyano-3[5-(5-piperidino-2-thienylcarbonyl)-2-thienyl]-2-propenoate within a poly[11-(N-carbazolyl)undecyl methacrylate] matrix. The electrooptic coefficient has been measured by both interferometric and polarimetric techniques. The interferometric technique was not appropriated because the strong electric field applied to the electrodes changes the film thickness of these low T_g materials. A value of up to 5 pm/V for the figure of merit n³(r₁₃ - r₃₃) has been reported for the dispersed material, which is 10 times higher than the corresponding grafted material, and a linear relationship between the poling intensity and the electrooptic coefficient has been observed for the two materials.