Polythiophenes substituted with hexyl, cyclohexyl and methyl at the 3
position, and poly(3,4-dihexylthiophene) were synthesized. The propert
ies of the polymers were characterized for conductivity, electroactivi
ty, mechanical and thermal stability using NMR, gel permeation chromat
ography, cyclic voltammetry and thermal gravimetric analysis. With bul
ky substituents, all the properties of the polymer are very much affec
ted as can be seen from poly (3-cyclohexylthiophene).