Nanoreactor-Assisted Polymerization Toward Stable Dispersions of Conductive Composite Particles Alexey N. Korovin, Vladimir G. Sergeyev, Olga A. Pyshkina, Christoph Hanske, Andreas Fery, Alexander Wittemann, Larisa Tsarkova* Introduction Improving the efficiency of chemical reactions by creating optimal conditions in confined environment is a trick which is widely used by nature. The principle of a chemical nanoreactor is selective localization and controlled release of reagents in a finite volume. [1] In this approach, complex soft materials such as micelles, vesicles, miniemulsions, polymersomes, or block copolymer microdomains are used as nanotemplates or nanoreactors. [2–6] The future of materials science and technology relies to a great extent on the development of smart effective synthetic approaches on the nanoscale. In this respect, the design of microstructured conductive polymer materials has a significant impact on advancing the technologies ranging from electronics to anticorrosion coatings. [7] In practice, the advantageous charge transport properties of conjugated polymers result in serious difficulties in processing of these materials, in blending of p-conjugated polymers with insulating polymer matrixes, and thus in poor control over the targeted structure. [8] Much effort has been devoted to drive the conducting component into a stable, continuous, percolat- ing phase. [4] One of the most attempted strategies to achieve a uniform spatial distribution of functional p- conjugated polymers is the preparation of core–shell particles via template polymerization. [9–14] In particular, polyaniline (PANi)-based core–shell particles have been Communication L. Tsarkova, A. N. Korovin, C. Hanske, A. Fery Physikalische Chemie II, Universita ¨t Bayreuth, 95440 Bayreuth, Germany E-mail: tsarkova@dwi.rwth-aachen.de A. N. Korovin, V. G. Sergeyev, O. A. Pyshkina Polymer Division, Department of Chemistry, Moscow State University, 119991 Moscow, Russia A. Wittemann Physikalische Chemie I, Universita ¨t Bayreuth, 95440 Bayreuth, Germany L. Tsarkova Current Address: DWI an der RWTH Aachen, 52056 Aachen, Germany We demonstrate the functioning of a macromolecular nanoreactor which guides a reaction in a confined volume and leads toward improved functional properties of a product material. In our approach, the polymerization of aniline (ANi) is conducted within the interfacial volume of spherical polyelectrolyte brushes (SPB) which are densely affixed to colloidal particles. The SPB provide optimal conditions for matrix polymerization by the efficient confinement of ANi monomers within the finite volume of polyelectrolyte brushes and controlled delivery of the oxidizing reagent to the reaction volume. The excellent kinetic stability of the resulting core– shell particles together with the high macro- scopic conductivity of the respective composite open up perspectives for novel materials (a conductive ink). 462 Macromol. Rapid Commun. 2011, 32, 462–467 ß 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim wileyonlinelibrary.com DOI: 10.1002/marc.201000626