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- Processing of poly(ionic liquid)-ionic liquid membranes using femtosecond (fs) laser radiation: Effect on CO2 separation performancePublication . Gouveia, Andreia S.L.; Oliveira, Vitor; Ferraria, Ana Maria; Rego, Ana; Ferreira, Maria João; Tomé, Liliana C.; Almeida, Amélia; Marrucho, I. M.Femtosecond (fs) laser micromachining on polymeric materials is a single-step, and contactless manufacturing technology. Knowing the potential of poly(ionic liquid)s (PILs) and their derived composite materials incorporating ionic liquids (PIL-IL) to design membranes with improved CO2 separation, we here explore for the first time the creation of microchannels on the surface of PIL-IL materials by laser ablation using femtosecond laser radiation. PIL-IL membranes composed of pyrrolidinium-based PILs containing the [NTf2](-) and [C(CN)(3)](-) anions and different amounts of their corresponding ILs (40 and 60 wt%) were prepared and micromachined using fs laser pulses varying the pulse repetition rate, scanning speed, and pulse energy. The morphology of the fs laser modified PIL-IL samples was investigated through scanning electron microscopy (SEM), while the influence of the fs laser processing on the membranes structure was analyzed by solid-state nuclear magnetic resonance (ssNMR), Fourier-transform infrared (FT-IR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). The CO2/N-2 and CO2/H-2 separation performances of the irradiated membranes were also evaluated and compared to those of the non-irradiated. Depending on the parameters used, fs laser processing was successful in modifying the surface of PIL-IL membranes through the formation of microchannels around 55-60 mu m deep. Significant improvements in CO2, N-2 and H-2 permeabilities were achieved for the irradiated PIL-IL membranes, maintaining their CO2/N-2 and CO2/H-2 permselectivities.
- High ionicity ionic liquids (HIILs): comparing the effect of ethylsulfonate and ethylsulfate anionsPublication . Oliveira, Filipe S.; Pereiro, Ana B.; Araújo, João M. M.; Bernardes, Carlos E. S.; Lopes, J N Canongia; Todorovic, Smilja; Feio, Gabriel; Almeida, Pedro L.; Rebelo, Luis Paulo; Marrucho, I. M.The subject of ionicity has been extensively discussed in the last decade, due to the importance of understanding the thermodynamic and thermophysical behaviour of ionic liquids. In our previous work, we established that ionic liquids' ionicity could be improved by the dissolution of simple inorganic salts in their milieu. In this work, a comparison between the thermophysical properties of two binary systems of ionic liquid + inorganic salt is presented. The effect of the ammonium thiocyanate salt on the ionicity of two similar ionic liquids, 1-ethyl-3-methylimidazolium ethylsulfonate and ethylsulfate, is investigated in terms of the related thermophysical properties, such as density, viscosity and ionic conductivity in the temperature range 298.15–323.15 K. In addition, spectroscopic (NMR and Raman) and molecular dynamic studies were conducted in order to better understand the interactions that occur at a molecular level. The obtained results reveal that although the two anions of the ionic liquid exhibit similar chemical structures, the presence of one additional oxygen in the ethylsulfate anion has a major impact on the thermophysical properties of the studied systems.
- Processing of poly(ionic liquid)-ionic liquid membranes using femtosecond (fs) laser radiation: Effect on CO2 separation performancePublication . Gouveia, Andreia S.L.; Oliveira, Vitor; Ferraria, Ana Maria; Rego, Ana; Ferreira, Maria João; Tomé, Liliana C.; Almeida, Amélia; Marrucho, I. M.Femtosecond (fs) laser micromachining on polymeric materials is a single-step, and contactless manufacturing technology. Knowing the potential of poly(ionic liquid)s (PILs) and their derived composite materials incorporating ionic liquids (PIL-IL) to design membranes with improved CO2 separation, we here explore for the first time the creation of microchannels on the surface of PIL-IL materials by laser ablation using femtosecond laser radiation. PIL-IL membranes composed of pyrrolidinium-based PILs containing the [NTf2](-) and [C(CN)(3)](-) anions and different amounts of their corresponding ILs (40 and 60 wt%) were prepared and micromachined using fs laser pulses varying the pulse repetition rate, scanning speed, and pulse energy. The morphology of the fs laser modified PIL-IL samples was investigated through scanning electron microscopy (SEM), while the influence of the fs laser processing on the membranes structure was analyzed by solid-state nuclear magnetic resonance (ssNMR), Fourier-transform infrared (FT-IR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). The CO2/N-2 and CO2/H-2 separation performances of the irradiated membranes were also evaluated and compared to those of the non-irradiated. Depending on the parameters used, fs laser processing was successful in modifying the surface of PIL-IL membranes through the formation of microchannels around 55-60 mu m deep. Significant improvements in CO2, N-2 and H-2 permeabilities were achieved for the irradiated PIL-IL membranes, maintaining their CO2/N-2 and CO2/H-2 permselectivities.
- Processing of poly(ionic liquid)-ionic liquid membranes using femtosecond (fs) laser radiation: Effect on CO2 separation performancePublication . Gouveia, Andreia S.L.; Oliveira, Vitor; Ferraria, Ana Maria; Rego, Ana; Ferreira, Maria João; Tomé, Liliana C.; Almeida, Amélia; Marrucho, I. M.Femtosecond (fs) laser micromachining on polymeric materials is a single-step, and contactless manufacturing technology. Knowing the potential of poly(ionic liquid)s (PILs) and their derived composite materials incorporating ionic liquids (PIL-IL) to design membranes with improved CO2 separation, we here explore for the first time the creation of microchannels on the surface of PIL-IL materials by laser ablation using femtosecond laser radiation. PIL-IL membranes composed of pyrrolidinium-based PILs containing the [NTf2](-) and [C(CN)(3)](-) anions and different amounts of their corresponding ILs (40 and 60 wt%) were prepared and micromachined using fs laser pulses varying the pulse repetition rate, scanning speed, and pulse energy. The morphology of the fs laser modified PIL-IL samples was investigated through scanning electron microscopy (SEM), while the influence of the fs laser processing on the membranes structure was analyzed by solid-state nuclear magnetic resonance (ssNMR), Fourier-transform infrared (FT-IR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). The CO2/N-2 and CO2/H-2 separation performances of the irradiated membranes were also evaluated and compared to those of the non-irradiated. Depending on the parameters used, fs laser processing was successful in modifying the surface of PIL-IL membranes through the formation of microchannels around 55-60 mu m deep. Significant improvements in CO2, N-2 and H-2 permeabilities were achieved for the irradiated PIL-IL membranes, maintaining their CO2/N-2 and CO2/H-2 permselectivities.