High-throughput optimization of nitroxide mediated radical polymerizations as basis for the synthesis of temperature-responsive copolymers

The development of controlled radical polymn. techniques, namely atom transfer radical polymn. (ATRP), reversible addn. fragmentation transfer (RAFT) and nitroxide mediated radical polymn. (NMP), have opened up unprecedented possibilities for the synthesis of well-defined macromol. architectures with a large no. of different monomers. In addn., well-defined polymers with LCST behavior have wound widespread interest for a use as -smart' responsive materials. Here we report our automated parallel investigations on the NMP of 2 hydroxypropylacrylate (HPA), N,N-dimethylacrylamide (DMA) and N-acryloyl morpholine (Amor) using BlocBuilder- nitroxide and addnl. free SG-1 nitroxide. The high-throughput approach allowed fast optimization of the polymn. procedure for solvent, temp. and concn. of free nitroxide. In addn., the optimal polymn. conditions were applied for the synthesis of systematical libraries of well-defined statistical copolymers based on HPA and DMA or Amor. The effect of monomer compn. on the thermal properties and thermoresponsiveness of the copolymers was studied in detail. [on SciFinder (R)]