Blue electroluminescent polymer and organo-electroluminescent device employing the same

1. A polymer represented by formula 1:

wherein:

Ar is selected from the group consisting of a substituted or unsubstituted C 6-30 aryl group and a substituted or unsubstituted C 2-30 heteroaryl group;

R 1 , R 2 , R 3 and R 4 are independently a hydrogen atom, a substituted or unsubstituted C 1-30 alkyl group, a substituted or unsubstituted C 1-30 alkoxy group, a substituted or unsubstituted C 6-30 aryl group, a substituted or unsubstituted C 6-30 arylalkyl group, a substituted or unsubstituted C 6-30 aryloxy group, a substituted or unsubstituted C 2-30 heteroaryl group, a substituted or unsubstituted C 2-30 heteroarylalkyl group, a substituted or unsubstituted C 2-30 heteroaryloxy group, a substituted or unsubstituted C 5-20 cycloalkyl group, and a substituted or unsubstituted C 5-30 heterocycloalkyl group;

n is a real number between 0.01 and 0.99; and

the polymer has a weight average molecular weight within the range of from about 10,000 to about 200,000 and a molecular weight distribution of 1.5 to 5.

2. The polymer of claim 1 , wherein in formula 1, the arylene (Ar) unit is a group represented by one or more formula selected from the group consisting of:

wherein R 5 and R 6 are independently selected from the group consisting of a hydrogen atom, a substituted or unsubstituted C 1-12 alkyl group, a substituted or unsubstituted C 1-12 alkoxy group and a substituted or unsubstituted amino group.

3. The polymer of claim 1 , wherein the arylene (Ar) unit has an alkyl fluorene structure as represented by formula 1 k or 1 m,

4. The polymer of claim 1 , wherein the polymer is a compound represented by formula 2:

wherein R 1 , R 2 , R 7 and R 8 are independently a C 1-12 alkyl group, and n is a real number between 0.01 and 0.99.

5. An organic EL device comprising an organic layer positioned between a pair of electrodes, the organic layer comprising the polymer of claim 1 .

6. The organic EL device of claim 5 , wherein the organic layer is an emissive layer or a hole transport layer.

7. The organic EL device of claim 5 , wherein in formula 1, the arylene (Ar) unit is a group represented by one or more formula selected from the group consisting of:

wherein R 5 and R 5 are independently selected from the group consisting of a hydrogen atom, a substituted or unsubstituted C 1-12 alkyl group, a substituted or unsubstituted C 1-12 alkoxy group and a substituted or unsubstituted amino group.

8. The organic EL device of claim 5 , wherein the polymer is a compound represented by formula 2:

wherein R 1 , R 2 , R 7 and R 8 are independently a C 1-12 alkyl group, and n is a real number between 0.01 and 0.99.