Synthesis and Optical Properties of a Copolymer of Tetrafluoro‐ and Dialkoxy‐Substituted Poly(p‐phenylenevinylene) with a High Percentage of Fluorinated Units
A copolymer of 2,3,5,6‐tetrafluoro‐1,4‐phenylenevinylene and 2,5‐dioctyloxy‐1,4‐phenylenevinylene co(TFPV‐DOPV)], containing more than 60% of tetrafluorophenylenevinylene monomeric units, was synthesized by the Stille cross‐coupling reaction. Its linear and nonlinear optical properties were investigated. Linear absorption and photoluminescence measurements performed on thin films and solution indicate interchain migration upon excitation. The Z‐scan technique was used to evaluate the third‐order nonlinear susceptibility at λ = 1064 nm. A very high refractive nonlinearity (n2 = (?10 ± 2) × 10?12 cm2 · W?1) was measured with a value one order of magnitude larger than that of the corresponding dialkoxy‐substituted homopolymer.
