Aromatic Polyimides as Efficient Materials for Organic Electroluminescent Devices

Derivatives of newly synthesized aromatic polyimides containing sulphur atoms in the backbone were studied as electron-hole-transporting and light-emitting materials for use in combination with tris(8-hydroxyquinoline)-aluminium in multilayer organic electroluminescent devices. Efficient bipolar charge transport has been revealed in the polymers. Bright electroluminescence (15 000 cd m -2 at 14V) was observed in the visible range. The possible role of intermolecular donor-acceptor interactions in the mechanism of electroluminescence is discussed.