SEARCH Articles Figures Tables 2- n-Butylthiophene 2- tert-Butylthiophene 3-methylthiophene/3-butylthiophene copolymers 3-octylthiophene/3-butylthiophene copolymers 3.4- Di-ferf-butylthiophene Poly(butylthiophene Structure of Poly-3-butylthiophene in