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MATERIAL SCIENCE
Of special interest are living radical polymerizations [5] which permit the synthesis of polymers with varied architectures, predetermined end groups and narrow molecular distributions. Additionally these polymerizations proceeded much more rapidly in ionic liquids than in conventional solvents. Electronically conducting polymers are also accessible by polymerizations of ionic liquid monomers as demonstrated by Ohno et al. [6]. A very new area in the field of ionic liquids is the preparation of nanoparticles [7]. Some other very recent publications describe the benefits of ionic liquids as new and versatile lubricants [8]. They show excellent friction reduction, antiwear performance and high load-carrying capacity. [1] P. Kubisa, Prog. Polm. Sci. , 2004 , 29. [2] Zhang, H.; Hong, K.; Mays, J. W. Macromolecules 2002 , 35 , 5738-5741 [3] P. Wasserscheid et al. J. Chem. Soc. Chem. Commun. 2001 , 1186-1187. [4] M. Jautelat, European Patent 2000 , EP 1035093. [5] Vijayaraghavan, R. MacFarlane, D. R. Chemical Communications 2004 , 6 , 700-701. [6] Yoshizawa, M.; Ogihara, W.; Ohno, H. Polymers for Advanced Technologies 2002 , 13 , 589-594. [7] M. Antonietti et al. Angew. Chem. Int. Ed. , 2004 , 43 , 4345. [8] Mu et al., Chem Lett. 2004 , 43 , 4345.
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NEWS
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The use of ionic liquids in polymer synthesis is a fairly recent development and the number of publications is relatively sparse in comparison with their use in organic synthesis or catalysis. This is somewhat surprising as the use of ionic liquids in polymer synthesis shows a number of benefits. For example reports show significant increase in the rate of polymer propagation in radical polymerisations [1]. The free radical polymerization of MMA in [BMIM][PF6] is one of the most widely studied examples and generates polymers with high molecular weights [2]. Transition-metal-catalyzed polymerizations like oligomerizations of ethylenes to higher ?-olefins with Ni-catalysts [3] or metathesis polymerizations [4] have also been performed in ionic liquids. For these polymerizations one has to use ionic liquids with low residual halide content in order to prevent poisoning of the transition metal catalyst.