Effect of the synthesis temperature and the length of alkyl substituents on photoelectrical properties of polyterthiophenes

Three poly(4,4 " -dipentoxy-3'-alkyl-2,2':5',2 " -terthiophene)s with diffe rent lengths of the alkyl side-chains (dodecyl, octyl and hexyl) were prepa red by cyclic voltammetry. The morphology of these polymers was found to be regular and to depend on the temperature of electrosynthesis. Better morph ology was obtained in all cases for polymers prepared at somewhat higher te mperatures (from 40 degreesC to 25 degreesC). The photoelectrical propertie s of the polymers were improved by decreasing the length of the alkyl side- chain. For the same alkyl chain length, better photoelectrical properties w ere found for polymers with a more regular morphology.