Novel fluorene-based polymers containing acetylene units

Novel fluorene-based polymers containing acetylene units for light-emitting and transporting materials were synthesized by oxidative coupling polycond ensations. 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-diethynylfluo rene}] [poly(BEHCEF-co-DHDEF)] was shown to be very soluble in common organ ic 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 (PV K) gave a narrow clear blue-light emission. The PL and EL characteristic st udies of the polymer films and their crosslinked products by thermal treatm ent were discussed.