Copolymers of thienylene were prepared by the Suzuki coupling reaction. For
alkylated copolymers of thienylene with 1,4-phenylene, substituent positio
n has similar effect on absorption and fluorescence spectra. For copolymers
with naphthylenes and biphenylene, absorption maxima occurred at different
positions but fluorescence spectra were confined in a narrow range of wave
length.