Synthesis and properties of self organising semiconducting and luminescentpolymers and model compounds

Oligothiophene-PEO-block-co-polymers and related model compounds have been synthesised and characterised. In the polymers well-defined oligothiophene blocks (with from two to six alpha,alpha -linked thiophene sequences) were alternated with poly(ethylene oxide) blocks of narrow polydispersity. Model alpha,alpha -linked sexithiophenes were prepared carrying chiral, achiral, mono and narrow polydispersity monomethyl PEO substituents at their termin al alpha positions. All the products were soluble in common organic solvent s and organic/aqueous solvent mixtures. UV/vis and fluorescence studies in solution indicated that the oligothiophene segments were molecularly dissol ved in good solvents like chloroform. Aggregation of the oligothiophenes oc curred in dioxane/water mixtures, consistent with observed shifts of the UV absorption maxima towards the blue and quenching of the fluorescence, An o ligothiophene length of three thiophenes (terthiophene) was necessary for a ggregation to be observed. The materials formed well-organised transferable monolayers at the air water interface.