New naphthalene diimide-based n-type copolymers: The effects of conjugated side chains

Two poly(naphthalene diimide)s (PNDIs) have been developed using p-phenylene ethynylene-based comonomers with either thiophene side chains (P(NDI-BT)) or bithiophene side chains (P(NDI-BBT)), and the effects of the length of conjugated side chains on electrochemical, optical, and morphological properties were investigated. Both polymers showed additional vibronic peaks due to the interchain π-π* transition, and a high absorption coefficient (α)...