In recent time, conjugated electroluminescent polymers have attracted much attention from both the scientific and practical viewpoint due to their application as electroactive materials for light-emitting diodes [1—3]. It has been found that intense electroluminescence (EL) in polymer requires high electron—hole conduction of a medium related to the mobility of charge carriers and a balance of injection of carriers of both signs from opposite electrodes into the emission polymeric layer. However, the majority of EL polymers are hole-transport materials, which leads to the imbalance of charge injection and a poor quantum yield. A search for new efficient electron-transport polymers is required to improve performance of electrooptical devices, which is achieved in particular by introducing into macromolecules electron-withdrawing fragments: triazole [4], oxadiazole [5], quinoline [6], and quinoxaline [7]. The latter is the least studied. One can suppose that polyphenylqui- noxalines (PPQs) will show higher electron-withdrawing properties owing to the presence of four electron-withdrawing heteroatoms. A promising approach to improve the quantum yield is provided not only by the balance of the electron and hole conduction but also by design of multilayer bipolar (donor—acceptor) emission polymers.
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