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BACKGROUND: Ionic liquids are regarded as future effective absorbents of CO 2 , however high viscosity of this medium limits its use in industry. To resolve the problem a mixture of alkanolamine, ionic liquids and water was proposed as a CO 2 absorbent and the influence of solution composition on the volume of CO 2 absorbed was determined. RESULTS:In most binary mixtures of ionic liquids and water tasted the presence of water does not affect the overall capacity of absorption mixture except for the 1-butyl-3-methylimidazolium acetate where each mol of water added to the mixture reduces the volume of CO 2 that could be absorbed by more than one mole. The capture of CO 2 using three-component systems of water/ionic liquid/monoethanolamine (MEA) was systematically investigated with two selected ionic liquids: 1-butyl-3-methylimidazolium acetate and 1-ethyl-3-methylimidazolium octylsulfate. It was shown that the volume of CO 2 absorbed is linearly dependent on the mass fraction of components for 1-ethyl-3-methylimidazolium octylsulfate over the entire experimental domain whereas in 1-butyl-3-methylimidazolium acetate the interaction between ionic liquid and water substantially decreases the volume of CO 2 absorbed. CONCLUSIONS: The best results for CO 2 absorption were obtained using the three component system 1-butyl-3methylimidazolium acetate/monoethanolamine/water. Optimization of the composition of an IL-MEA-water mixture allows tuning of the properties of the medium. The CO 2 absorption capacity of the mixture is mainly a function of MEA concentration and, to a lesser degree, of the concentration of IL possessing chemisorption abilities. The presence of water decreases the viscosity of the mixture and therefore facilitates the application of IL-based media in industrial applications.

Five ionic liquids based on a quaternary ammonium core substituted with a D-glucose moiety and alkyl chains of varying length were synthesized as prospective phase-transfer catalysts. The catalytic activity of the obtained ionic liquids was tested in the dehydrochlorination of 3,4-dichloro-1-butene to chloroprene. The reaction proceeded in a two-phase system in the presence of an aqueous solution of sodium hydroxide. The results showed that the longer the alkyl chain in the cation, the higher the activity of the ionic liquid as a phase-transfer catalyst. The tested ionic liquids gave an easily recyclable system compared to classical phase-transfer catalysts that were soluble in the reaction system, with no leaching observed over five cycles (chloroprene yield >99%). The cytotoxicity and biodegradability of a series of synthesized ionic liquids based on D-glucose were determined so that a preliminary hazard assessment could be undertaken.

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Copolymers of [2-(methacryloyloxy)ethyl]trimethylammonium chloride, salicylate or bis(trifluoromethanesulfonate)imide (Cl − , Sal − or Tf 2 N − ), and methyl methacrylate (MMA) were synthesized by atom transfer radical polymerization (ATRP). The effect of different molar fractions of ionic monomer (0.05−1.0) on physicochemical properties was investigated. The relative reactivity ratios of MMA and ionic monomer with the chloride anion (0.88 and 1.13, respectively) were determined by the linearization Jaacks method. The particles formed in water by copolymers with trimethylammonium chloride (≥50 mol %) reached sizes below 10 nm, whereas salicylate-containing copolymers supported strong self-assembly, yielding 200 nm superstructures. The copolymers, after modification by the exchange of Cl − and Sal − with Tf 2 N − , demonstrated the influence of the anion on solubility, glass transition temperature, and morphology. The anionmodified trimethylammonium copolymers, compared with those directly synthesized from Tf 2 N-containing monomer, indicated different properties. Both the chloride monomer (Cl − replaced by Sal − or Tf 2 N − ) and its copolymers are able to exchange anions, including biologically active ones, which extends their future applications as poly(ionic liquid)s with therapeutic properties for controlled drug delivery.

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The new polymeric systems for delivery in cosmetology applications were prepared using self-assembling amphiphilic graft copolymers. The synthesis based on “click” chemistry reaction included grafting of azide-functionalized polyethylene glycol (PEG-N3) onto multifunctional polymethacrylates containing alkyne units. The latter ones were obtained via atom transfer radical polymerization (ATRP) of alkyne-functionalized monomers, e.g., ester of hexynoic acid and 2-hydroxyethyl methacrylate (AlHEMA) with methyl methacrylate (MMA), using bromoester-modified retinol (RETBr) as the initiator. Varying the content of alkyne moieties adjusted by initial monomer ratios of AlHEMA/MMA was advantageous for the achievement of a well-defined grafting degree. The designed amphiphilic graft copolymers P((HEMA-graft-PEG)-co-MMA), showing tendency to micellization in aqueous solution at room temperature, were encapsulated with arbutin (ARB) or vitamin C (VitC) with high efficiencies (>50%). In vitro experiments carried out in the phosphate-buffered saline solution (PBS) at pH 7.4 indicated the maximum release of ARB after at least 20 min and VitC within 10 min. The fast release of the selected antioxidants and skin-lightening agents by these micellar systems is satisfactory for applications in cosmetology, where they can be used as the components of masks, creams, and wraps.

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