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Propagation rate coefficients, kp, of methyl methacrylate (MMA) and glycidyl methacrylate (GMA) homopolymerizations were measured at ambient pressure in four ionic liquids (ILs): 1‐ethyl‐3‐methylimidazolium ([emim]) ethyl sulfate and [emim] hexyl sulfate as well as butyl‐3‐methylimidazolium ([bmim]) hexafluorophosphate and [bmim] tetrafluoroborate via the pulsed‐laser polymerization size‐exclusion chromatography technique. In passing from bulk polymerization at 40 °C polymerization in IL solution containing 20 vol % monomer, kp is enhanced by up to a factor of 4 with MMA and by a factor of 2 with GMA. This enhancement of kp primarily results from a lowering of activation energy upon partial replacement of monomer by ionic liquid species. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1460–1469, 2008

Nafion 117 membranes were impregnated with various imidazolium (1-hexyl-3-methyl-imidazolium/HMI, 1-butyl-3-methyl-imidazolium/BMI) and pyrrolidinium (1-butyl-1-methyl-pyrrolidinium/BMPyr) based ionic liquids bearing hydrophobic (tris(pentafluoroethyl)trifluorophosphate/FAP, bis(trifluoromethylsulfonyl)imide/BTSI, hexafluorophosphate/PF 6 ) and more hydrophilic (tetrafluoroborate/BF 4 ) anions. The modified membranes were characterized in terms of uptake behavior, washing out of the ionic liquids by water, swelling in humidified environment, thermal stability, mechanical properties, ion exchange capacity and ion conductivity. Upon this treatment, the ionic liquids' cations partially replace the protons of the sulfonic acid groups in Nafion. While the ionic liquids act as potent plasticizers in the polymer matrix, thermal stability of these systems remains unchanged and swelling by water of the dried ionomer membranes is reduced. Ion conductivities at 120°C under dry conditions have been found to be up to 100 times higher than for dry Nafion 117. In particular, modification of Nafion by ionic liquids bearing the bulky hydrophobic FAP anion seems promising.

By grafting 4‐vinylpyridine (4VP), N‐vinylformamide (NVF), and 1‐vinylimidazole (1VIm) onto electron beam irradiated ETFE and FEP films, the basic membrane matrices ETFE‐graft‐poly(4VP), FEP‐graft‐poly(4VP), ETFE‐graft‐poly(1VIm), and ETFE‐graft‐poly(vinylamine), after subsequent hydrolysis of ETFE‐graft‐poly(NVF), can be obtained. These matrices are doped with phosphoric acid to produce acid–base composite materials that exhibit high proton conductivities up to 100 mS · cm−1 at high temperatures (120 °C) and no humidification. The produced membranes are robust, flexible, and mechanically stable even at high doping levels and endure temperatures of up to 160 °C. Preliminary tests in H2/O2 fuel cells provide power densities between 75 and 150 mA · cm−2 at 120 °C without humidification.magnified image

Mn(salen)Cl was applied as a low‐cost catalyst for the formation of alkoxyamines from nitroxides and substituted styrenes. These “unimolecular initiators” for nitroxide‐mediated radical polymerization (NMRP) were synthesized using 2,2,6,6‐tetramethyl‐1‐piperidine‐1‐oxyl and 2,2,5‐trimethyl‐4‐phenyl‐3‐azahexane‐3‐oxyl. Functionalized alkoxyamines were obtained from 4‐vinylbenzyl chloride and 4‐vinylbenzyl alcohol. The divinyl compound 1,2‐bis(4‐vinylphenyl)ethane was converted to an alkoxyamine monomer and to bisaminooxy compounds, which can be used as “biradical initiators” for NMRP.Formation of alkoxyamines using Mn(salen)Cl as the catalyst.magnified imageFormation of alkoxyamines using Mn(salen)Cl as the catalyst.