Polarized fluorescence and electroluminescence from rubbing-aligned conjugated polymers and their composites with fluorescent dyes

Polarized fluorescence and optical absorption studies of rubbing-treated poly(2,5-diheptyloxybenzene) and poly (3-alkylthiophene)s (PATs) were carried out with the aim of obtaining polarized electroluminescence (EL). It was revealed that there exists an optimum alkyl chain length in PATs for the effect of rubbing. Polarized EL with a dichroic ratio of 2.6 was observed from a rubbing-aligned PAT-12 film. It was also demonstrated that the rubbing treatment of composite films of PAT and several fluorescent dyes such as 1,4-bis (2-methylstyryl)benzene enabled us to obtain polarized emission from oriented dye molecules. © 1997 John Wiley & Sons, Ltd.