Electroluminescent -conjugated polymers

The enormous progress in the field of electroluminescent conjugated polymers has led to performances of oiganic light-emitting devices (LEDs) that are comparable and in some aspects superior to their inorganic counterparts 11). Quantum efficiencies in excess of 5% have been demonstrated [2] and show that a high fraction of the injected carriers in a polymeric electroluminescence (EL) device form electronic excitations which recombine radiatively. 

Light-emitting diodes (LEDs) based on the electroluminescent conjugated polymers (Fig. 47) have attracted significant attention, both in academic research and industrial development, and are now on the edge of commercialization (Burroughs et al. 1990, Barth and Bassler 1997). Polymer LEDs require properties such as shown in Table 11. Recently, ef-... 

A Kraft, AC Grimsdale, and AB Holmes, Electroluminescent conjugated polymers — seeing polymers in a new light, Angew. Chem. Int. Ed., 37 402-428, 1998. 

J. Pei, W.-L. Yu, W. Huang, and A.J. Heeger, The synthesis and characterization of an efficient green electroluminescent conjugated polymer poly[2,7-h s(4-hexylthienyl)-9,9-dihexylfluorene], Chem. Commune. 1631-1632, 2000. 

Kraft A, Grimsdale AC, Holmes AB Angew Chem Int Ed (1998) 37 403-428 Electroluminescent conjugated polymers - seeing polymers in a new light... 

R Jakubiak, CJ Collison, WC Wan, LJ Rothberg, BR Hsieh. Aggregation quenching of luminescence in electroluminescent conjugated polymers. J Phys Chem A 103 14, 2394-2398, 1999. 

In thin films of electroluminescent conjugated polymers, Kanner et al. [12] and Yan et al. [13] explained the quenching of PL by invoking an exciton migration mechanism to nonradiative traps based on the Balagurov-Vaks model [14], The survival probability of an exciton on a 1-D lattice (fi- = 1/3) is characterized by a diffusion time t(i. For times t t,i. the PL intensity follows... 

Kraft, A., Grimsdale, A.C. and Holmes, A.B. (1998) Electroluminescent conjugated polymers - Seeing polymers in a new light. Angewandte Chemie (International Ed. in English), 37, 402-28. 

Figure 6.1 Schematic representation of a monolayer OLED incorporating an electroluminescent conjugated polymer between a transparent anode and a cathode.

M. Pope and C. E. Swenberg. Electronic Processes in Organic Crystals and Polymers. Oxford University Press, 2nd edition, 1999. C. M. Ramsdale and N. C. Greenham. Ellipsometric determination of anisotropic optical constants in electroluminescent conjugated polymers. Adv. Mater., 14(3) 212, 2002. 

Poly(p-phenylene vinylene) (PPV) belongs to the class of electroluminescent conjugated polymers. These materials emit light when electric current is passed through them. For this reason, a substantial interest emerges in the field of organic semiconductors. 

Electroluminescent conjugated polymers can be synthesized by incorporating high electronegative heterocyclic groups, such as 1,3,4-oxadiazole, 1,3,4-thiadiazole and 1,2,4-triazole moieties. These electroluminescent polymers are obtained by polymerization of a bis-(halomethyl) aromatic monomer modified with a heterocyclic group. ... 

A. Kraft, A. Grimsdale, A.B. Holmes, Electroluminescent Conjugated Polymers -Seeing Polymers in a New Light, Angew. Chem. Int. Ed. 37 (1998) 402. 

PLECs represent a dynamic research subject toward their promising applications in future lighting and display devices. Unlike PLEDs, the active materials of PLECs are composed of ionically conductive species and the electroluminescent conjugated polymer. 

The phenomenon of electroluminescence has been observed in a wide range of semiconductors and was first reported for an organic semiconductor by Pope et al. in 1963. The discoveiy of electroluminescent conjugated polymers, that is a class of fluorescent polymer that emit light when excited by the flow of an electric current, was an exciting advance in the field of light emitting devices. 

A. Kraft, A. C. Grimsdale, and A. B. Holmes, Electroluminescent conjugated polymers—seeing polymers in a new light. Angew Chem Internal Edm (1998), 402-28. 

Tsutsumi, N., Nishida, H. Tunable distributed feedback lasing with low threshold and high slope efficiency Irom electroluminescent conjugated polymer waveguide. Opt. Commun. 284, 3365-3368 (2011)... 

---