High cost and high energy penalty for CO uptake from flue gases are important obstacles in large-scale industrial applications, and developing efficient technology for CO capture from technical and economic points is crucial. Ionic liquids (ILs) show the potential for CO separation owing to their inherent advantages, and have been proposed as alternatives to overcome the drawbacks of conventional sorbents. Chemical modification of ILs to improve their performance in CO absorption has received more attention. Deep eutectic solvents (DESs) as a new generation of ILs are considered as more economical alternatives to cope with the deficiencies of high cost and high viscosity of conventional ILs. This Review discusses the potential of functionalized ILs and DESs as CO sorbents. Incorporation of CO -philic functional groups, such as amine, in cation and/or anion moiety of ILs can promot their absorption capacity. In general, the functionalization of the anion part of ILs is more effective than the cation part. DESs represent favorable solvent properties and are capable of capturing CO , but the research work is scarce and undeveloped compared to the studies conducted on ILs. It is possible to develop novel DESs with promising absorption capacity. However, more investigation needs to be carried out on the mechanism of CO sorption of DESs to clarify how these novel sorbents can be adjusted and fine-tuned to be best tailored as optimized media for CO capture.

35 novel DESs are synthesized and screened in terms of their CO2 solubility and viscosity.

No abstract

No abstract

No abstract

No abstract

The electroresponsive, dielectric and swelling behavior of semi-interpenetrated polymer network (semi-IPN) gel films prepared from chitosan (CS) and N,N-dimethyl acrylamide (DA) were investigated and compared with those CS film. CS–DA semi-IPN films were also characterized by Fourier transform infrared, x-ray diffraction and differential scanning calorimetry measurements. The electrosensitivity of CS–DA films to an electric field was investigated by determining their bending at 8 V in (0.05 M/0.1 M/0.15 M) NaCl solution. Equilibrium swelling values of CS–DA films both in distilled water and buffer solution with pH = 2.2 decreased with poly-DA (PDA) content of the films. While the maximum decomposition of CS film took place at about 296 °C, the presence of PDA in CS–DA semi-IPN films reduced the thermal stability, and their maximum decomposition temperature shifted from 261 to 240 °C with the increase in PDA content. In addition, the PDA network led to a decrease in the dielectric constant (ε′), dielectric loss (ε″) and conductance (σ) of CS–DA semi-IPN films in the frequency range between 12 Hz and 100 kHz. The values of electric modulus and impedance, and Cole–Cole plots confirmed that the conductance values of CS–DA films are lower than that of CS film. The PDA network also led CS–DA films to respond more slowly to electric field. The increase in NaCl concentration in the bending medium increased the response rate of CS–DA films to an electric field. The final bending angle of all CS–DA films was 90°, and it was not dependent on either NaCl concentration or PDA content of the films.

In this study, Ca 21 -crosslinked sodium alginate (SA) gel films (SA-Ca/SA2-Ca) have been prepared, and their structural and thermal characterizations were investigated using fourier transform infrared spectroscopy, Xray diffraction, differential scanning calorimetry, and thermogravimetric analysis, respectively. Dielectric characterization was performed at room temperature in the frequency range of 12 Hz-100 kHz. The equilibrium swelling value (ESV) of gel films was determined both in distilled water and in 0.1 M sodium chloride (NaCl) solution at room temperature. Sodium alginate films (SA/ SA2) were also prepared for use as reference. The effect of the crosslinking of sodium alginate on the dielectric and thermal properties of gel films was investigated by comparing the properties of gel films with those of SA/ SA2 films. Although ESV of Ca 21 -crosslinked SA film in distilled water is about 350 g H 2 O /g polymer , it decreased into one third in 0.1 M NaCl solution. The crosslinking of SA did not significantly affect the thermal properties, but it decreased the b-relaxation associated with the polar side groups. Frequency spectra of electric modulus, impedance and Cole-Cole plots confirmed the higher conductance values of SA-Ca films at low frequencies than those of SA film due to the presence of by-product of crosslinking. POLYM. ENG. SCI., 54:1372-1382,