Synthesis and properties of poly(arylene vinylene)s with controlled structures

Poly(arylene vinylene)s (PAVs) have attracted interest as the light emitting layer in LEDs. Such polymers may be made by several routes. We have used McMurry, Yamamoto and Suzuki methodologies to make different PAVs. We synthesised polymers with para and also with meta linkages between phenylene and vinylene groups in an attempt to increase the energy gap and to shift the light emitting wavelength towards the blue region. The number and geometrical connectivities of the phenylenes constituting the arylene portion of the repeat unit and the cis/trans distribution have been varied in a controlled way. Relatively high molecular weight samples were produced by equilibrium fractionation. Results correlating the details of polymer structure with the observed photoluminescence are discussed. (C) 1999 Elsevier Science B.V. All rights reserved.