A series of new conjugated rigid-rod polymer poly(9

9-alkyl fluorenolbenzo bisoxazole)s (PBOPFx) containing an fluorene and benzobisoxazole structures were synthesized by 4

6-diamino-1

3-benzenediol-dihydrochloride (DAR) and 9

9-dialkyl-2

7-dicarboxyl fluorine

The polymer was characterized by the elemental analysis

1H-NMR

FTIR

thermogravimetric analysis (TGA) and photoluminescence (PL) spectra.The absorption and photoluminescence spectra of the polymers were also studied.The protonated PBOPFx in methanesulfonic acid solutions exhibits a blue emission with a peak at 466 nm or so.In contrast with that of PBO

the maximal emissions spectra and absorption spectra of PBOF red-shifted due to the introduction of the fluorene group which enhanced effective conjugation of polymer structure unit.In addition

emission spectrum of PBOPFx at 320 nm and 430 nm were compared

the Oxidationreduction curve is observed

and at last that PBOPFx solution has two conjugated units was verified

but two conjugated units did not show a clear separation

electronic transmission occurred in hybrid

so PBOPFx mostly showed the absorption and emission of the main conjugated unit.Also as a result of existence of alkyl side chains in fluorene unit

the thermal stability of polymers (PBOPFx) is lower than polyphenylene Benzodiazepine oxazoline (PBO)polymer

the initial decomposition temperature is about 350℃

but in the respect of dissolved character

PBOPFx has a great improvement

can well dissolved in most organic solvents.