Electrically conducting polypyrroles as multifunctional coupling agents in heterogeneous polymer blends

POLY 63

Jan Hegewald, hegewald@ipfdd.de, Jürgen Pionteck, Petra Pötschke, poe@ipfdd.de, Lothar Jakisch, and Brigitte Voit. Leibniz Institute of Polymer Research Dresden, Hohe Str. 6, Dresden, D-01069, Germany
A novel approach will be presented using nanometer sized electrically conducting polypyrrole particles not only to induce conductivity to a polymer blend but also to improve its mechanical properties by interfacial compatibilization. A model blend system was chosen, based on mono-amino terminated polystyrene and carboxylic acid endgroup functionalized poly(methyl methacrylate), synthesized by ATRP and RAFT, respectively. However, carboxylic acid and amine groups do not undergo a coupling reaction during melt mixing. This fact is utilized to incorporate electrically conducting polypyrroles, containing 1,3-oxazoline and 1,3-oxazinone moieties, which selectively react with carboxylic acid and amino groups, respectively. Thus polypyrrole locates selectively at the interface, building up percolation paths. On condition of a co-continuous morphology an electrically conductive bulk material is obtained with a reduced threshold concentration. The challenge is to fit size and reactivity of the polypyrroles to the domain size of the blend, so that it can act effectively as interfacial modifier.