Two oligoethers containing electroactive pendent pyridinyl-carbazole moieties have been synthesized by the multi-step synthetic route. Full characterization of their structures is presented. The oligomers represent derivatives of very high thermal stability with initial thermal degradation temperatures exceeding 400 degrees C. Glass transition temperatures of the amorphous materials were also very high and reached values of 124 degrees C and 145 degrees C, respectively. Bipolar chemical structure having oligomer, i.e. poly{3-(2-methoxy-3-pyridinyl)-9-(3-methyloxetan-3-yl)methyl-carbazole} was tested as host material for green phosphorescent organic light emitting diode using tris(2-phenylpyridine)iridium(III) as a triplet emitter. A green device containing 10 wt% of the green guest demonstrated among all the devices the best performance with current efficiency of 8.8 cd/A and power efficiency of 5.1 lm/W at 100 cd/m(2). At higher brightness, such as 1000 cd/m(2), used for illumination applications, this PhOLED showed enhanced efficiency of 11.7 cd/A (5.4 lm/W) with brightness exceeding 4000 cd/m(2).