<title>Aromatic ethers with 1,3,5-triazine units as hole-blocking/electron-transport materials in LEDs</title>

Various fluoro-functionalized aromatic 1,3,5-triazine monomers were prepared. A series low molar mass and poly- (1,3,5-triazine)-ethers were synthesized by a condensation reaction. The polymers as well as the low molar mass compounds have excellent thermal stability and are amorphous. In order to examine the potential to apply these compounds in organic electroluminescent devices, the redox properties were studied by cyclic voltammetry. It was found that the monomers have high electron affinity and reach LUMO values in the range of -2.7 to -3.1 eV. Additionally high oxidation stability with HOMO values lower than -6.4 eV follows hole blocking capabilities. This opens the possibility to utilize 1,3,5-triazine containing materials as electron injection/hole blocking layer in LEDs. First LED results are in agreement to these high electron affinities.