Luminescent poly(phenylene vinylene) derivatives with m-terphenyl or 2,6-diphenylpyridine kinked segments along the main chain:: Synthesis, characterization, and stimulated emission

Two new poly(phenylene vinylene)s containing m-terphenyl or 2,6-diphenylpyridine kinked units along the main chain were synthesized and were used as luminescent and laser materials. They were prepared from Heck coupling of 2,5didodecyloxy-1,4-divinylbenzene with 4,4"-dibromo-3'-phenyl-m-terphenyl or 2,6-di(4-bromophenyl)-4-phenylpyridine. The kinked units along the main chain caused a partial interruption of the conjugation leading to emission at a shorter wavelength as compared with poly(p-phenylene vinylene). The polymers presented blue-green emission in solution and green-yellow emission in the solid state with photoluminescence maxima at 465-497 and 546-550 nm, respectively. Polymer containing 2,6-diphenylpyridine segments emitted at a longer wavelength than that containing m-terphenyl and displayed higher quantum yields in solution (0.61 and 0.40, respectively). The influence of the solvent and polymer concentration on the photoluminescence characteristics was investigated. The photoluminescence properties of protonated polymer containing 2,6-diphenylpyridine segments were investigated both in solution and in film. Amplified spontaneous emission and tunable laser action were also obtained from the two polymers. (C) 2004 Wiley Periodicals, Inc.