Influence of Anion Structure on Thermal, Mechanical and CO2 Solubility Properties of UV-Cross-Linked Poly(ethylene glycol) Diacrylate Iongels

Abstract

Iongel-based CO2 separation membranes were prepared by fast (< 1 min) UV-initiated polymerization of poly(ethylene glycol) diacrylate (PEGDA) in the presence of different ionic liquids (ILs) with the [C2mim]+ cation and anions such as [TFSI]−, [FSI]−, [C(CN)3]− and [B(CN)4]−. The four ILs were completely miscible with the non-ionic PEGDA network. Transparent and free-standing iongels containing between 60 and 90 %wt of IL were obtained and characterized by diverse techniques (FTIR, TGA, DSC, DMTA, SEM, CO2 solubility and pure gas permeability). The thermal and mechanical stability of the iongels, as well as CO2 solubility, were found to be strictly dependent on the IL content and the anion’s nature. The TGA results indicated that the iongels mostly follow the thermal profile of the respective neat ILs. The DMTA analysis revealed that the iongels based on fluorinated anions have higher storage modulus than those of cyano-functionalized anions. Conversely, the PEGDA–C(CN)3 iongels presented the highest CO2 solubility values ranging from 72 to 80 mmol/g. Single CO2 permeabilities of 583 ± 29 Barrer and ideal CO2/N2 selectivities of 66 ± 3 were obtained with the PEGDA–70 C(CN)3 iongel membrane. This work demonstrates that the combination of PEGDA with high contents of the best performing ILs is a promising and simple strategy, opening up new possibilities in the design of high-performance iongel membranes for CO2 separation.

Preparation, Characterization, and Biocompatibility Assessment of Polymer-Ceramic Composites Loaded with Salvia officinalis Extract

“…These C-H stretching vibrations are also clearly visible in composites and PVP. The peak at 1727 cm −1 was observed in association with the C=O stretching frequency [44]. This peak was also clearly visible on the spectrum of samples 17, 17.2, 25, and 25.2.…”

“…Figure 2 presents the absorption spectra for pure components as well The absorption band of the PEGDA sample at 2858 cm −1 was attribut stretching vibration, while 790 cm −1 represented the C-H bending mo stretching vibrations are also clearly visible in composites and PVP. The pe was observed in association with the C=O stretching frequency [44]. This clearly visible on the spectrum of samples composition of the incubation media.…”

Toward the Recycling of Low-GWP Hydrofluorocarbon/Hydrofluoroolefin Refrigerant Mixtures Using Composite Ionic Liquid–Polymer Membranes

“…Understanding the effect of pressure on the membrane gas solubility is a critical aspect for designing membrane-based separation processes, particularly regarding the permeation of highly soluble penetrants such as CO 2 , organic vapors, and fluorinated hydrocarbon gases, whose transport properties through rubbery polymers strongly depend on pressure. − Thus, we have studied the sorption behavior of R32, R134a, and R1234yf as a function of pressure in CILPMs. For this study, we selected the CILPM materials with the best performance in terms of R32/R1234yf and R134a/R1234yf permselectivity and stability toward feed pressure, that is, the CILPMs with 40 wt % [C 2 mim]­[SCN] and [C 2 mim]­[BF 4 ], as well as the neat polymer Pebax 1657, for the sake of comparison.…”

Poly(ethylene glycol) Diacrylate Iongel Membranes Reinforced with Nanoclays for CO2 Separation

“…For the fabrication of iongels, there is a wide variety of materials that can be selected, as well as diverse routes to approach their preparation [11]. In order to ensure that high IL contents (>50 wt%) are efficiently retained within the iongel structure, different types of gelators can be used [11], such as polymer networks [12], block copolymers [13], biopolymers [14], supramolecular gelators [15], organosilane networks [16], or inorganic nanoparticles [17]. The combination of ILs with polymers, which are commercially available such as poly(vinylidene fluoride) (PVDF) [18] or poly(ethylene glycol) (PEG) [19], and poly(ionic liquid)s (PILs) with imidazolium [20] or pyrrolidinium [21] cations and a variety of counter anions, is perhaps the most straightforward approach to fabricate iongel membranes.…”

“…The polymerization can be thermal or UV initiated. Recently, Martins et al [12] studied the influence of the anion structure on the CO 2 /N 2 separation performance of UV-cross-linked poly(ethylene glycol) diacrylate (PEGDA) iongels. Using imidazolium-based ILs with cyano-functionalized ([C(CN) 3 ]and [B(CN) 4 ] -) or fluorinated anions ([TFSI]and [FSI] -), self-standing iongels containing between 60 and 90 wt% of IL were obtained.…”