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Photopolymerization of poly(ethylene glycol) monomethacrylate (PEGMM) in two imidazolium based ionic liquids (ILs) differing with the anion size and H-bond accepting ability, i.e. 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIm][BF 4 ]) and 1-ethyl-3-methylimidazolium trifluoroacetate ([EMIm][ATF]) was investigated to find the effect of the IL anion on propagation k p and termination rate k t b coefficients (by DSC) as well as molecular interactions in the system (on the basis of viscosity and FT-IR measurements). Polymerizations in bulk and in tricresyl phosphate (TCP) served as references. Both monomer/IL systems show strong viscosity synergism and viscosity deviations are positive indicating that viscosity of associates between the monomer and the ILs is relatively higher than that of pure components. The increase in k p values observed in ILs is higher for polymerization in [EMIm][BF 4 ], which shows stronger Coulomb cation-anion attractions and lower H-bond accepting ability of the anion. The influence of the ionic liquids on the termination rate coefficient results from the viscosity of the monomer-IL system, taking account of viscosity synergism. On the basis of changes of imidazolium ring CH groups vibrations and carbonyl stretching vibrations (both in PEGMM and IL anion) two possible configurations of monomer-IL interactions were proposed: between the monomer carbonyl and C(2)-H hydrogen of the imidazolium cation in the case of [EMIm][BF 4 ] and a configuration in which the monomer carbonyl interacts with the imidazolium cation located on the top of the ring, in the case of [EMIm][ATF].

Fourier Transform Infrared spectroscopy (FTIR) and Wide-Angle X-Ray Diffraction (WAXD) measurements have\ud clearly established the occurrence of a dual sorption ability of sulfonated syndiotactic polystyrene samples, which\ud exhibit the nanoporous d crystalline phase. In fact, large uptake (up to 20–30 wt%) of ionic liquid (IL; e.g. 1-ethyl-\ud 3-methylimidazolium dicyanamide) occurs only in the hydrophilic amorphous sulfonated phases and does not disturb\ud the hydrophobic nanoporous crystalline d phase. On the other hand, a large uptake of organic guests (e.g. naphthalene)\ud occurs prevailingly in the nanoporous hydrophobic crystalline phase, independently of the presence of the IL in the amorphous\ud phase, eventually leading to the formation of syndiotactic polystyrene co-crystalline phases. The thermal stability\ud of IL can be largely increased by their inclusion in the amorphous phase of sulfonated syndiotactic polystyrene films