Novel fluorene-based polymers containing acetylene units

Abstract

Novel fluorene-based polymers containing acetylene units for light-emitting and transporting materials were synthesized by oxidative coupling polycondensations. The resulting copolymer, for example, poly[{2,7-bis(4-ethynyl)-9-n-hexyl-9 '-(2-cyanoethyl)fluorene}-co-{9,9'- di-n-hexyl-2,7-diethynylfluorene}] [poly(BEHCEF-co-DHDEF)] was shown to be very soluble in common organic solvents, highly luminescent, stable up to 300 degreesC and also easily cast to give good thin films. The cure temperature was measured around 270 degreesC by DSC. While EL spectrum of this polymer showed a broad yellowish-white emission, EL spectrum of the blended one with polyvinylcarbazole (PVK) gave a narrow clear blue-light emission. The PL and EL characteristic studies of the polymer films and their crosslinked products by thermal treatment were discussed.