Blue electroluminescent polymer and organic electroluminescence device using the same

1. A blue electroluminescent polymer, represented by the following formula (1):

wherein the electroluminescent polymer has a number average molecular weight from 10,000 to 200,000, and a molecular weight distribution from 1.5 to 5;

wherein Ar is a C 6-26 aromatic group, or a C 4-14 heteroaromatic group which contains at least one heteroatom in the aromatic ring, where the aromatic group and the heteroaromatic group may be unsubstituted or substituted with at least one C 1-12 linear, branched or cyclic alkyl group, alkoxy group or amine group;

R and R′ are independently a hydrogen atom, a C 1-12 linear, branched or cyclic alkyl group or alkoxy group, or a C 6-14 aromatic group which may be unsubstituted or substituted with at least one C 1-12 linear, branched or cyclic alkyl group, alkoxy group or amine group; and

n is a real number from 0.01 to 0.99.

2. The blue electroluminescent polymer as set forth in claim 1 , wherein the Ar unit is selected from the group consisting of structures represented by the following formulas (2) and (3):

wherein R 1 and R 2 are independently a C 1-12 linear, branched or cyclic alkyl group, alkoxy group or amine group.

3. The blue electroluminescent polymer as set forth in claim 2 , wherein the Ar unit is an alkylfluorene.

4. The blue electroluminescent polymer as set forth in claim 3 , wherein the Ar unit is a dioctylfluorene unit.

5. An organic electroluminescence device comprising the blue electroluminescent polymer as set forth in claim 1 as a light-emitting layer.

6. The organic electroluminescent device as set forth in claim 5 , wherein the Ar unit is selected from the group consisting of structures represented by the following formulas (2) and (3):

wherein R 1 and R 2 are independently a C 1-12 linear, branched or cyclic alkyl group, alkoxy group or amine group.

7. The organic electroluminescent device as set forth in claim 6 , wherein the Ar unit is an alkylfluorene.

8. The organic electroluminescent device as set forth in claim 7 , wherein the Ar unit is a dioctylfluorene unit.

9. The organic electroluminescent device as claimed in claim 5 , wherein the device has a structure selected from the group consisting of anode/light-emitting layer/cathode, anode/buffer layer/light-emitting layer/cathode, anode/hole transport layer/light-emitting layer/cathode, anode/buffer layer/hole transport layer/light-emitting layer/cathode, anode/buffer layer/hole transport layer/light-emitting layer/electron transport layer/cathode, and anode/buffer layer/hole transport layer/light-emitting layer/hole blocking layer/cathode.