SYNTHESIS AND STRUCTURE-PROPERTY RELATIONS OF POLYMERS FOR LIGHT-EMITTING-DIODES BASED ON ISOLATED CHROMOPHORE UNITS

New fluorescent polymers for electroluminescent devices were synthesiz ed and characterized. In order to obtain polymers for blue light emitt ing diodes (LEDs), two different structural concepts based on isolatio n of the active chromophore units within the polymer main chain were i nvestigated. In the first approach non-coplanar units were used to red uce the conjugation length in poly(arylenevinylene)s. In a second appr oach copolymers having isolated chromophore units in the polymer main chain were investigated. For this purpose, copolyesters containing iso lated 1,2-dinaphthylethene chromophore units were synthesized and char acterized. The influence of the chemical structure on the photo- and e lectroluminescence is discussed. On the example of copolyester 2b, whi ch shows bluegreen electroluminescence (lambda(max) = 497 nm) in a LED configuration, it was demonstrated that these polyesters can be used as light emitting layer in electrooptical devices.