TECHNOLOGY FOCUS - ELECTRONICS - Preferred Device: Layer(s) containing the organic electroluminescent polymer is provided between anode (12) and cathode (16) in an organic electroluminescent device. The layer(s) is hole transport layer (13) or light-emitting layer (14). The structure of the electroluminescent element is anode/light-emitting layer/cathode, anode/hole transport layer/light-emitting layer/cathode or anode/hole transport layer/light-emitting layer/electron transport layer (15)/cathode.    TECHNOLOGY FOCUS - POLYMERS - Preparation: No general preparation given. Preferred Polymer: The organic electroluminescent polymer has average molecular weight of 800-4000000 and molecular weight distribution of 1-10. Preferred Definitions:    Ar2=optionally substituted 6-60C arylene, 2-60C hetero aromatic ring optionally containing fluorine, sulfur, nitrogen, oxygen, phosphorus or silicon, 6-60C optionally substituted arylene vinylene, or aryl optionally substituted by 1-20C alkyl or alkoxy, optionally substituted by cyano or silyl group.    EXAMPLE - 9-(9,9-Dihexyl fluorene-2-yl)-2,7-dibromo fluorene-9-ol (I) was reacted with methane sulfonic acid and 1,2-di(2-methyl)butyloxy benzene in dichloromethane to obtain 2,7-dibromo-9-(9,9-dihexylfluorene-2-yl)-9-(3,4-di(2-methyl)butyloxy phenyl)fluorene (M1) (58.8 g). The monomer (M1) was converted to 9-(9,9-dihexyl fluorene-2-yl)-9-(3,4-di(2-methylbutyloxyphenyl)fluorene)-2,7-diboronic acid compound using n-butyl lithium, triethoxy borane and proton, and the obtained compound was reacted with dihydroxy ethane and anhydrous toluene to obtain 9-(9,9-dihexyl)fluorene-2-yl-9-(3,4-di(2-methyl)butyloxy phenyl)fluorene-2,7-bis-boro glycol ester (M2) (50.2 g). The compound (I) was reacted with dihexyl fluorene in presence of methane sulfonic acid to obtain 9,9-di(9,9-dihexylfluorene-2-yl)-2,7-dibromo fluorene (M3) (37.3 g). The monomer (M1) (in mol%) (15), monomer (M2) (50), monomer (M3) (20), dibromophenyl-dimethoxyphenyl-diphenyl diamine (M4) (12) and a fluorene-containing bis(diphenyl-dihexyl fluorenyl-fluorene amine)-bistyryl-biphenyl (M5) were polymerized to obtain an organic electroluminescent polymer with number average molecular weight of 155000 and weight average molecular weight of 390000. The organic electroluminescent device produced using the polymer had high luminous efficiency.