Nanopatterned Electrochromic Conjugated Poly(terthiophene)s via Thermal Nanoimprint Lithography of Precursor Polymer

Polyterthiophene nanostructures consisting of periodic nanolines were prepared using the precursor polymer approach in conjunction with nanoimprint lithography. Precursor polynorbornylenes consisting of terthiophene side chains were prepared from their corresponding norbornylene monomers via ring opening metathesis polymerization. A copolymer consisting of terthiophene norbornylene and acetate norbornylene repeat units with a 50:50 composition exhibited a glass transition temperature of 52°C. Nanolines of percursor polynorbornylene were prepared by thermal nanoimprint lithography. The nanoimprinted precursor polymer was then converted to conjugated conductive polymer via chemical and electrochemical oxidation of the terthiophene side units. Nanoimprinted lines of conductive polyterthiophene exhibited high electrochromic contrast at 437 nm.