Final Activity Report Summary - CONDPOLS-2 (Development of new polymer materials with electrical conductivity and stimuli-sensitive attributes) During the project several stimuli-sensitive polymers with electrical conductivity were prepared. Based on poly (p-phenylene ethynylene)s (PPEs), a class of conjugated, (semi)conducting polymers with interesting optical properties with normally linear, rod-like molecules, hyperbranched derivatives were synthesised. These polymers demonstrated a better processability compared to covalent cross-linked polymers of the same class. Their charge-carrier mobility was higher than that of linear polymers. Using metalo-supramolecular chemistry new optical decoupled PPEs build from oligo-PPE precursors equipped with complex-binding chain ends and metal salts were developed. The polymers showed good mechanical properties and emitted light under electrical stimulation (electroluminiscence). Within the project, a Light emitting device (LED) was build from these polymers. Furthermore a new PPE derivative containing proton accepting groups in the side chain (dialkylamino) was prepared and nanocomposites with biological material, cellulose whiskers isolated from the tunikate styela clava were manufactured. These composites had much better mechanical properties than the pure conjugated polymers that were used, such as PANI and PPE alone. Based on these findings, a new method for the preparation of cellulose nanocomposites with several other non-conjugated polymers, such as polystyrene was also developed. Finally, new redox sensitive PPEs were developed during the project. They provided redox sensitive moieties which could be easily oxidised and reduced. As proven in the project, these polymers were not cytotoxic and were usable in sensor applications for single cell monitoring devices, which were currently under development by GKSS by the time of the project completion. As a result of this project, a new research group for the use of conjugated polymers in the development of biomaterials was established in 2008 at the GKSS research centre, in the Centre for Biomaterial Development, in Teltow campus.
