Dopant macroinitiator for electropolymerisation and functionalisation of conducting polymer thin films

Abstract

Grafting of polymer brushes from conducting polymer (CP) thin films by controlled radical polymerisation provides a versatile route for the synthesis of functional, electroactive surfaces, with applications in diverse fields. However, drawbacks of this approach include difficulty in upscaling synthesis due to the need for specialised CP precursor monomers functionalised with initiation sites. We herein describe an alternative approach to the synthesis of CP-based polymer brushes whereby ATRP initiation sites are attached to a macrodopant incorporated into CP films during electropolymerisation. The facile electropolymerisation of commonly studied CPs (PEDOT, PPy, and PTTh) with an initiator-functionalised macrodopant - poly(styrene sulfonate-co-(2-bromopropionyloxy ethyl methacrylate)) (PeesBro) – is demonstrated. The composite polymer films thus synthesised were used as substrates for grafting of hydrophilic polymer brushes. Although PSS is commonly used as a macrodopant in CP films, its initiator-functionalised derivatives have not previously been utilised in this manner. Despite the elegance of this approach, the authors’ knowledge, there have been no previous examples reported of utilising macromolecular dopants as initiators for subsequent grafting of polymer brushes.