Amphiphilic Block Copolymers Containing Regioregular Poly(3‐hexylthiophene) and Poly(2‐ethyl‐2‐oxazoline)

Poly(3-hexylthiophene)-block-poly(2-ethyl-2-oxazoline) amphiphilic rod-coil diblock copolymers have been synthesized by a combination of Grignard metathesis (GRIM) and ring-opening cationic polymerization. Diblock copolymers containing 5, 15, and 30 mol-% poly(2-ethyl-2-oxazoline) have been synthesized and characterized. The synthesized rod-coil block copolymers display nanofibrillar morphology where the density of the nanofibrills is dependent on the concentration of the poly(2-ethyl-2-oxazoline) coil segment. The conductivity of the diblock copolymers was lowered from 200 to 35 S · cm -1 with an increase in the content of the insulating poly(2-ethyl-2-oxazoline) block. By contrast, the field-effect mobility decreased by 2-3 orders of magnitude upon the incorporation of the poly(2-ethyl-2-oxazoline) insulating segment.