Synthesis of Amphiphilic Block Copolymers Containing Chiral Polythiophene Chains and Their Micelle Formation and Chiroptical Properties.

Amphiphilic block copolymers consisting of hydrophobic regioregular head-to-tail (HT) chiral (()-poly---poly-) or achiral (poly---poly-) polythiophene chains and a hydrophilic poly(acrylic acid) chain were synthesized. ()-Poly---poly- with a chiral polythiophene block formed a micelle in water that exhibited a characteristic induced circular dichroism (ICD) in the π⁻π* transition region due to the formation of supramolecular π-stacked chiral aggregates of the chiral polythiophene blocks in the core. These aggregates were stable, showing no precipitation for more than 5 days. Micelles consisting of chiral ()-poly---poly- and achiral poly---poly- showed negative nonlinear effects on supramolecular chiral aggregate formation in the core. Chiral polythiophene aggregates formed in ()-poly---poly- micelle cores were stabilized by the crosslinking of poly(acrylic acid) blocks with diamines in the shell. The ICD intensity of the ()-poly---poly- micelle after shell crosslinking showed almost no change with temperature, while that before shell crosslinking decreased with increasing temperature.