Self-assembled Block Copolymers with Various Architectures Designed by ATRP

Exploring Atom Transfer Radical Polymerization, ATRP, and using the basic concepts to construct a particular advanced material, a number of novel block copolymers has been designed (1-3). Additionally the properties of new macromolecular architectures have been utilized (4-5). Below are presented the principal block copolymer architectures based on pentafluorostyrene (FS), synthesized from us (1, 4). They can be applied for any other monomers polymerizing under ATRP conditions too. Block copolymers display a very interesting phase behavior. Depending on the chemical nature and the size of the macromolecular building blocks they self assemble in attractive morphologies and exhibit interesting rheology. The designed at the Danish Polymer Centre by ATRP self-assembling block copolymers will be demonstrated by several examples: i. Diblock copolymers of PMMA with side chain liquid crystalline (LC) azopolymethacrylate blocks exhibit a LC phase, lamellar nanostructure and are suitable as stable volume holographic storage materials (3). ii. Amphiphilic triblock copolymers with a central ionophilic polyether block and flanking ionophobic PFS blocks phase separate by forming physically cross-linked polyether networks and demonstrate good Li+ complexation and conductivity. These make the materials a potential for solid electrolyte applications in Li+ ion batteries (4, 6). iii. Amphiphilic water soluble star block copolymers with a polyacrylic acid core form hydrogels at room temperature above concentration 22g/L do to hydrophobic association of the PS blocks in the corona. Effect of the hydrophobe length and polymer topology has been additionally investigated (6). iv. Hydrophilic nanoporous polymers with various morphologies and pore size (7) have been mastered by novel synthetic strategies using two methodologies, which will be discussed. In contact with water, they showed spontaneous water uptake (8). References (1). Hansen, N.M.L.; Jankova, K.; Hvilsted, S. European Polymer Journal 43(2), pp 255-293 (2007); Bednarek, M.; Jankova, K.; Hvilsted, S. J. Polym. Sci., Part A: Polym. Chem. 45, pp 333-340 (2007); Dimitrov, I.; Jankova, K; Hvilsted, S. Polymer Preprints 48(2), pp 196-197 (2007); J. Polym. Sci., Part A: Polym. Chem. (2008). In Print. (2). Jankova, K.; Chen, X.; Kops, J.; Batsberg, W. Macromolecules 31, pp 538-541 (1998). (3). Forcén, P.; Oriol, L.; Sánchez, C.; Alkalá, R.; Hvilsted, S.; Jankova, K.; Loos, J. J. Polym. Sci., Part A: Polym. Chem. 45, pp 1899-1910 (2007); European Polymer Journal 43, pp 3292-3300 (2007); ibid, 44, pp 72-78 (2008); Journal of Applied Physics 103, 123111 (2008). (4). Jankova, K.; Hvilsted, S. J. Fluorine Chemistry 126(2), pp 241-250 (2005). (5). Hietala, S.; Mononen, P.; Strandman, S.; Järvi, P.; Torkkeli, M.; Jankova, K.; Hvilsted, S.; Tenhu, H. Polymer, 48(14), pp 4087-4096 (2007); Macromolecules 2008. Submitted. (6). Jankova, K.; Jannasch, P.; Hvilsted, S. Journal of Materials Chemistry 14, pp 2902-2908 (2004). (7). Ndoni S.; Vigild M.E.; Berg R.H. JACS 125(44), pp 13366-13367 (2003). (8). Guo, F.; Jankova, K.; Schulte, L.; Vigild, M.E.; Ndoni, S. Macromolecules 41, pp 1486-1493 (2008); Polymer Preprints 49(2), pp 540-541 (2008).