Conjugated polymer chains self-assembly: A new method to generate (semi)-conducting nanowires?

The morphology of thin films of conjugated polymers and block copolymers (containing one conjugated segment and one (or two) non-conjugated segments) is analysed with a combination of atomic force microscopy data and molecular mechanics/dynamics calculations. The rigid character of the conjugated segment induces specific morphological characteristics, with respect to the situation usually found in coil - coil copolymers. The copolymers organise as very long, thin objects with constant width and height in the nanometre range (nanoribbons). Decreasing the amount of polymer on the substrate allows the observation of isolated nanoribbons. The comparison of the experimental data with the theoretical modelling indicates that the ribbons are made of highly regular stacks of conjugated chains surrounded by coiled non-conjugated segments.