Poly Ethylene Glycol Dimethyl Ether Research Articles

The plasticizer-free composite block copolymer electrolytes for ultralong lifespan all-solid-state lithium-metal batteries

Solid polymer electrolytes (SPEs) are regarded as one of the most promising substitutes for liquid electrolytes to construct highly safe electrochemical energy storage. While liquid plasticizers are frequently employed in SPEs to enhance ionic conductivity, it is inevitably accompanied by a deficiency in safety. Herein, we report plasticizer-free composite block copolymer electrolytes (BCEs) with conductive nanodomains for ultralong lifespan all-solid-state Li-metal batteries (ASSLBs). The composite BCEs with poly(ether-block-amide) (Pebax) block copolymer as a conductive framework and polyethylene glycol dimethyl ether (PEGDE) as a regulator, can connect and manipulate the highly conductive nanodomains. Compared with homopolymer poly(ethylene oxide) (PEO), the conductive nanodomains in composite BCEs with tunable size can manipulate the Li+ transport channel, effectively enhancing the Li+ conductivity and homogenizing the Li+ deposition. In addition, the thin and dense hybrid solid electrolyte interface (SEI) layer, as well as the potent mechanical strength of composite BCEs, can synergistically suppress the dendrite growth. Therefore, the all-solid-state LiFePO4/Li cells achieve impressive electrochemical performance with a tiny capacity reduction of 0.0127% per cycle for more than 1350 cycles at 0.5 C. This work aims to give impetus to the development of practical ASSLBs which meet the demands for high safety, long lifespan, and mass production.

Superior CO2/N2 separation performance of highly branched Poly(1,3 dioxolane) plasticized by polyethylene glycol

With its high content of CO 2 -philic ether oxygen groups, poly(1,3-dioxolane) (PDXLA) has emerged as an attractive platform to achieve excellent CO 2 /N 2 separation properties for post-combustion carbon capture. Herein we demonstrate that the separation properties of PDXLA can be further enhanced by plasticizing with miscible polyethylene glycol (PEG)-based additives using an integrated experimentation and modeling approach. The effects of the chain end groups and loading level of the additives on the physical properties of the blends are thoroughly investigated, including glass transition temperature ( T g ), fractional free volume, and gas transport properties, and the effects can be satisfactorily described using models available for homogeneous blends. Notably, a T g -integrated free volume model is adapted to successfully interpret the unified effect of the blend composition and temperature on gas diffusivity and permeability. A sample containing 45 mass% PEG dimethyl ether (PEGDME with a molecular mass of 240 g/mol) displays stable mixed-gas CO 2 permeability of 1540 Barrer and CO 2 /N 2 selectivity of 40 when challenged with a model flue gas at 60 °C, outperforming Robeson's 2008 upper bound. Elucidating how small plasticizers impact gas transport in homogeneous blends may unravel a facile way to design high-performance membranes for gas separations. Enhancing CO 2 /N 2 separation performance of poly(1,3 dioxolane) by plasticizing with polyethylene glycol derivatives. • Homogeneous blends were prepared from poly(1,3 dioxolane) and polyethylene glycol. • Plasticization decreases T g and increases free volume and gas permeability. • Lower molecular weight PEG without OH groups show more plasticization impact. • Effect of temperature and composition on gas permeability is described using the free volume model. • Blends exhibit stable mixed-gas CO 2 /N 2 separation performance above the upper bound.

Determination and correlation of naproxen solubility in polyethylene glycol dimethyl ether 250 and water mixtures

ABSTRACT The equilibrium solubility of naproxen (NAP) in the mixtures of polyethylene glycol dimethyl ether 250 (PEGDME 250) and water is determined at different temperatures (293.15–313.15 K). Some cosolvency models including the van’t Hoff, the mixture response surface (MRS), the Jouyban-Acree, the Jouyban-Acree–van’t Hoff, the combined nearly ideal binary solvent/Redlich–Kister (CNIBS/R-K), the Buchowski–Ksiazczak, the modified Wilson (MW) and the MW–van’t Hoff models can describe the equilibrium of solid–liquid systems successfully. Therefore, the performance of these models in correlation of current data was examined by calculation of average relative deviation (ARD%). The results present a good applicability of selected models in correlation of NAP solubilities; however, the van’t Hoff, CNIBS/R-K, MRS and Jouyban-Acree models (ARDs% ≤15.3) were more applicable than the others. At the end, the respective apparent thermodynamic quantities of dissolution and mixing processes, namely Gibb’s energy, enthalpy and entropy, are computed based on the van’t Hoff and Gibbs equations.

Bosentan solubility in binary mixtures of polyethylene glycol dimethyl ether 250 and water at different temperatures

ABSTRACT This work reports the solubility of bosentan (BST) in some binary mixtures of polyethylene glycol dimethyl ether 250 (PEGDME 250) and water at different temperatures, i.e. 293.15–313.15 K under atmospheric pressure (≈ 85 kPa). Increasing the solubility of BST is observed with an increase temperature as well as PEGDME 250 portion with the maximum value in neat PEGDME 250 at 313.15 K. Some cosolvency models such as the Jouyban-Acree, the Jouyban-Acree-van’t Hoff, and the double log-log models were also used to correlate the experimental solubility data and the untested data were predicted based on the obtained trained models.

Synthesis and Characterization of a LiFe0.6Mn0.4PO4 Olivine Cathode for Application in a New Lithium Polymer Battery

AbstractA LiFe0.6Mn0.4PO4 (LFMP) cathode exploiting the olivine structure is herein synthesized and characterized in terms of structure, morphology, and electrochemical features in a lithium cell. The material shows reversibility of the electrochemical process which evolves at 3.5 and 4 V versus Li+/Li due to the Fe+2/Fe+3 and Mn+2/Mn+3 redox couples, respectively, as determined by cyclic voltammetry. The LFMP has a well‐defined olivine structure revealed by X‐ray diffraction, a morphology consisting of submicron particle aggregated into micrometric clusters as indicated by scanning and transmission electron microscopy, with a carbon weight ratio of about 4% as suggested by thermogravimetry. The electrode is used in lithium cells subjected to galvanostatic cycling with a conventional liquid electrolyte, and demonstrates a maximum capacity of 130 mAh g−1, satisfactory rate capability, excellent efficiency, and a stable trend. Therefore, the material is studied in a lithium metal polymer cell exploiting an electrolyte based on polyethylene glycol dimethyl ether with a solid configuration. The cell reveals very promising features in terms of capacity, efficiency, and retention, and suggests the LFMP material as a suitable electrode for polymer batteries characterized by increased energy density and remarkable safety.

Non-flammable liquid polymer-in-salt electrolyte enabling secure and dendrite-free lithium metal battery

Lithium-metal batterie (LMB) is regarded as one the most promising high energy battery systems, however the safety concern from lithium dendrites and organic liquid electrolytes seriously impedes its widely application. Herein, a non-flammable liquid “polymer-in-salt” composite electrolyte with superior dendrite-suppression capability is well designed and achieved by using lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt, polyethylene glycol dimethyl ether (PEGDME) and 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropylether (TTE). Non-flammable TTE used here is on one hand to reduce the high viscosity of this “PEGDME polymer in LiTFSI salt” electrolyte (PISE), and thus enhance its wettability; on the other hand, to maintain the merits of highly contented salt. By taking advantage of these localized highly concentrated lithium salts, aggregated ion clusters are generated in this PISE-TTE system, which construct fast ionic transportation channels, and thus accelerates Li+ transportation. Furthermore, this PISE-TTE electrolyte system interacts with Li anode forming a robust organic/inorganic dual layer solid electrolyte interphase (SEI) layer. With the assistance of this tough SEI, the optimized PISE0.7-TTE90 exhibits outstanding anti-dendrite growth behavior in Li/Li and Li/Cu cells. Moreover, PISE0.7-TTE90 also delivers an impressive performance in both Li/LiFePO4 (LFP, a capacity of 150 mAh g−1 at 0.5C after 150 cycles) and Li@Cu/LFP (electrochemically deposited Li on Cu current collector, a capacity of 150 mAh g−1 at 0.5C after 50 cycles) cells.

Increasing the electrochemical stability window for polyethylene-oxide-based solid polymer electrolytes by understanding the affecting factors

Polyethylene oxide (PEO) is the most widely used polymer matrix for solid polymer electrolytes (SPE) due to its flexibility and good solubility of lithium salts. However, PEO-based electrolytes are incompatible with high-voltage cathodes due to their limited electrochemical stability windows (ESW, ≤4 V). This work prepares membrane-supported PEO-based electrolyte membranes via a melt-infusion process and studies various factors affecting the ESW of the membranes, which include supporting material, terminal group, molecular weight, and temperature. The results show that the glass fiber-supported poly(ethylene glycol)-dimethyl ether (PEGDME) electrolyte with the molecular weight of 2000 shows good thermal stability, high ionic conductivity (3.22 × 10−4 S cm−1 at room temperature), and good electrochemical stability. This electrolyte enables the Li/SPE/Li symmetric cell to cycle over 900 h with an area-specific capacity of 1 mAh cm−2, and the LiNi0.6Mn0.2Co0.2O2 (NMC622)/SPE/Li half-cell to stably cycle for 100 cycles in the range of 2.5–4.2 V with a capacity retention of 85.7%. This work shows that the PEGDME-based membrane should be a promising SPE for solid-state lithium batteries.

Safe, Flexible, and High-Performing Gel-Polymer Electrolyte for Rechargeable Lithium Metal Batteries

The use of gel polymer electrolytes (GPEs) is of great interest to build high-performing rechargeable lithium metal batteries (LMBs) owing to the combination of good electrochemical properties and improved safety. Herein, we report a facile and scalable one-pot preparation method of a GPE based on highly safe polyethylene glycol dimethyl ether (PEGDME) plasticizer in a poly(vinylidenefluoride-co-hexafluoropropylene) (PVDF-HFP) polymer matrix. The prepared GPE exhibits excellent safety (nonflammability and thermal stability up to 250 °C) and outstanding electrochemical properties at room temperature (high ionic conductivity of 3.4 × 10–4 S cm–1 and high lithium transference number). Moreover, high loading LiFePO4 (6–7 mg cm–2) LMB using such GPE delivers a good C-rate response and high capacity (ca. 1 mAh cm–2 at C/10) with an excellent retention of 98% after 60 cycles in coin cell configuration. Notably, the prototype pouch cell (ca. 19 mAh at C/10) provides remarkable safety, mechanical flexibility, and strong tolerance toward bending and cutting. These results suggest that the prepared GPE is a promising candidate for the development of high performance, flexible, and safe LMBs that operate at room temperature, as well as for other energy storage systems beyond lithium-ion technologies.

Lithium Metal Deposition and Stripping in Porous Hosts Coupled with Viscous Polymer Electrolytes

High energy density rechargeable batteries are desired to meet global goals of increased use of renewable energy and vehicle electrification. Higher energy densities can be achieved by replacing graphite anodes with metal anodes. Among metal anode materials, lithium metal anodes are promising due to their high theoretical capacity and low reduction potential. However, obstacles such as dendrite growth and continuous electrolyte decomposition need to be addressed for successful commercialization of rechargeable batteries with lithium metal anodes. It is widely reported that porous 3D lithium metal hosts can mitigate dendrite growth by accommodating lithium deposition uniformly within the hosts during cycling. Continuous electrolyte decomposition can also be mitigated by replacing liquid electrolytes with solvent-free electrolytes. We incorporate both strategies in this work to address the critical issues described above by demonstrating lithium deposition/stripping cycling on 3D electrode hosts with viscous polymer electrolytes. First, lithium metal deposition/stripping cycling within non-conductive and conductive hosts were compared, where zinc oxide (ZnO) coated polyacrylonitrile (PAN) nanofibers was used as the non-conductive lithium metal host and ZnO coated copper nanowires were prepared as the conductive lithium metal host. The non-conductive host showed successful cycling of 5 mAh/cm2(25 µm thickness) of lithium metal without short circuiting. Further, deposition/stripping cycling with viscous star polymers (polystyrene-co-poly(polyethylene glycol) methyl ether acrylate (PS-co-PPEGMA)) and a linear oligomer polyethylene glycol dimethyl ether (PEGDME) were compared. The effects of the physical and electrochemical properties of the polymer electrolytes on lithium deposition and interfacial impedance will be discussed.

Novel Lithium‐Sulfur Polymer Battery Operating at Moderate Temperature

AbstractA safe lithium‐sulfur (Li−S) battery employs a composite polymer electrolyte based on a poly(ethylene glycol) dimethyl ether (PEGDME) solid at room temperature. The electrolyte membrane enables a stable and reversible Li−S electrochemical process already at 50 °C, with low resistance at the electrode/electrolyte interphase and fast Li+ transport. The relatively low molecular weight of the PEGDME and the optimal membrane composition in terms of salts and ceramic allow a liquid‐like Li−S conversion reaction by heating at moderately high temperature, still holding the solid‐like polymer state of the cell. Therefore, the electrochemical reaction of the polymer Li−S cell is characterized by the typical dissolution of lithium polysulfides into the electrolyte medium during discharge and the subsequent deposition of sulfur at the electrode/electrolyte interphase during charge. On the other hand, the remarkable thermal stability of the composite polymer electrolyte (up to 300 °C) suggests a lithium‐metal battery with safety content significantly higher than that using the common, flammable liquid solutions. Hence, the Li−S polymer battery delivers at 50 °C and 2 V a stable capacity approaching 700 mAh gS−1, with a steady‐state coulombic efficiency of 98 %. These results suggest a novel, alternative approach to achieve safe, high‐energy batteries with solid polymer configuration.

Synthesis and properties of symmetric glycerol-derived 1,2,3-triethers and 1,3-diether-2-ketones for CO2 absorption

Five compounds bearing glycerol skeletons: 1,3-diethoxypropan-2-one ([E, K, E]), 2,5,9,12-tetraoxatridecan-7-one ([ME, K, ME]), 1,3-bis(2,2,2-trifluoroethoxy)propan-2-one ([F, K, F]), 7-(2-methoxyethoxy)-2,5,9,12-tetraoxatridecane ([ME, ME, ME]) and 2-(2-methoxyethoxy)-1,3-bis(2,2,2-trifluoroethoxy)propane ([F, ME, F]) – were synthesized from epichlorohydrin at molar scales with high regioselectivity. Density and viscosity were measured over a temperature range of 293.15 to 353.15 K. Henry’s constants for CO2 were obtained under moderate pressures (2 to 10 atm) at 303.15, 318.15, 333.15 and 348.15 K. Comparison of CO2 affinity with dimethyl ethers of polyethylene glycol (DMPEG) and ionic liquids (ILs) indicated that [ME, ME, ME] and [F, ME, F] are excellent candidates as novel physical solvents for CO2 capture. DFT calculations were performed to understand the structure–property-performance relationships for the CO2 absorption mechanism. All five compounds were miscible with most common solvents except hexanes and water. In addition to gas absorption applications, these compounds might also find use as general purpose green solvents.

CO2 capture using ionic liquid-based hybrid solvents from experiment to process evaluation

The CO2 absorption capacity in three hybrid solvents based on butyl-3-methylimidazolium acetate ([Bmim][OAc]) and three different cosolvents (Dimethyl ethers of polyethylene glycol (DEPG250), propylene carbonate, and water) was investigated and compared, and [Bmim][OAc]-DEPG250 shows the highest CO2 absorption capacity. The effects of the mass ratio of [Bmim][OAc]-DEPG250 and temperature on their CO2 absorption capacity, density, and viscosity were further investigated. In addition, the absorption capacities of N2 and CO2 in [Bmim][OAc]-DEPG250 with the simulated flue gas as a feed gas were studied and compared with that using the pure gas as a feed gas. Thermodynamic models were used to represent the experimental data, and then process simulation and evaluation were carried out. The results show that the addition of DEPG250 dramatically decreases the viscosity, while the absorption capacity of hybrid solvents is still comparable with pure [Bmim][OAc]. The type of gas stream, that is, pure gas or gas mixture, has a negligible effect on the N2 and CO2 absorption capacity. The simulation results show that [Bmim][OAc]-DEPG250 only utilizes less than 50% of the heating duty of aqueous amine solution because of the low-pressure desorption and preheating with waste heat in this hybrid solvent-based process. The CO2 capture cost of using this [Bmim][OAc]-DEPG250 reduces by 11% compared with that of using aqueous amine solution due to the significant decrease (by 52%) in utility cost.

Searching for suitable lubricants for low global warming potential refrigerant R513A using molecular-based models: Solubility and performance in refrigeration cycles

• Accurate molecular thermodynamic model for R513A/lubricants in refrigeration cycles. • Rigorous energetic investigation of refrigeration cycles with thermodynamic postulates. • PEC5 optimal lubricant for R513A, in view of solubility, miscibility and viscosity. • Procedure allowed quantifying impact of the presence of lubricant on the COP. • Presence of PEC5 in the mixture up to 5% weight led to COP decrease of 3%. Following environmental regulations, refrigerant R134a (Global Warming Potential GWP = 1430), commonly used in air conditioning applications, is required to be replaced by refrigerants with lower GWP. Among them, R513A is investigated as an excellent alternative, with a GWP reduction of 56% compared to R134a. However, further studies are needed in order to assess its use for this application. In this work, the molecular-based polar soft-SAFT equation has been employed to predict the vapour-liquid equilibria (VLE) of R513A and selected lubricants, searching for the optimal lubricant and their performance on a vapour compression refrigeration cycle. First, the binary VLE of the commercial lubricants from the Pentaerythritol Esters (PECs) and Polyethylene Glycol Dimethyl Ethers (PEGDMEs) families with R1234yf and R134a were assessed versus available experimental data, by developing the appropriate molecular models and parameters. Then, the models were used to predict the properties of the ternary mixtures containing the two refrigerants and the lubricants. PEC5 was found to be the optimal lubricant for R513A, considering a balance between solubility, miscibility and viscosity. Molecular modelling combined with thermodynamic and energetic analysis allowed to calculate the performance of a vapour compression refrigeration cooling cycle, quantifying the impact of the presence of the lubricant on the COP. The presence of PEC5 in the mixture was not significant, staying below a COP decrease of 3% in all cases considered, while for TrEGDME, its presence reduced the COP up to 6.1%. The procedure used here allows tuning the performance of the refrigerant/lubricant pair, in a step forward on the search for low GWP refrigerants in air conditioning systems.

CaA, NaX, NaY ve ZSM-5 Sentetik Zeolitleri Üzerine Adsorbe Edilen Polietilen Glikol (Mono- ve Di- Metil) Eterin Kırmızıaltı ve Raman Spektroskopileri ile Analizi

The adsorptions of polyethylene glycol monomethyl ether (PEGMME) and polyethylene glycol dimethyl ether (PEGDME) on CaA, NaX, NaY, and ZSM-5 zeolites have been analyzed by using experimental FT-IR and Raman spectroscopies. The vibration wavenumbers of polymers adsorbed on zeolites have been reported and the adsorption properties of zeolites with different molecular sizes and cations have been compared. Disappearing of some vibration modes of polymers or shifts to the higher and lower frequency region after the polymers have been adsorbed on zeolites; indicates an interaction between polymers and zeolites. By considering the obtained experimental spectral results we can suggest that the source of adsorption of polymers on zeolites can be based on the interactions between OH groups or oxygen atoms settled in polymer chains and the silanol hydroxyl groups on the surface of each zeolite.

Enhancing CO2 utilization by a physical absorption-based technique in microalgae culture.

Carbon dioxide supplementation is significant for cell growth in autotrophic cultures of microalgae. However, the CO2 utilization efficiency is quite low in most processes. Aimed at this problem, six kinds of physical absorption enhancers were investigated to enhance the biological carbon sequestration of microalgae. By the addition of a small amount of CO2 absorption enhancer, the total inorganic carbon concentration of the medium was significantly increased. In addition, the biomass productivity of Scenedesmus dimorphus was maximally increased by 63% by the addition of propylene carbonate in flask cultures. In cultures using an air-lift photobioreactor equipped with a pH-feedback control system to supply CO2, the CO2 consumption was maximally reduced by 71% with added polyethylene glycol dimethyl ether. This study indicates that the incorporation of physical absorption enhancers could be a promising approach to overcome the problems of low CO2 utilization efficiency and high carbon source cost in algal biomass production.

Thermodynamics of CO2 separation with the superbase derived ionic liquid -- organic solvent binary system

In this work, the CO2 absorption capacity of superbase derived ionic liquid, i.e., 1,8-diazabicyclo [5,4,0] undec-7-ene imidazole ([HDBU][IM]) mixed with three different cosolvents (dimethyl ethers of polyethylene glycol (DEPG), propylene carbonate, and ethylene glycol) was studied, and [HDBU][IM]-DEPG was selected for further investigation, showing [HDBU][IM]-DEPG with 2:1 mass ratio at the temperature of 298.15 K exhibits the optimal performance of CO2 absorption capacity and viscosity. The gas solubilities for CH4, N2, and two gas mixtures (75% N2 + 25% CO2; 60% CH4 + 40% CO2) were studied, indicating the selectivity can be up to 17, and the real selectivity is higher than the ideal one. Thermodynamic modelling was carried out, and the species distributions, as well as the physical and chemical contributions, were analyzed, illustrating the reliability of the thermodynamic model with an average relative deviation lower than 2.37%. The decreased DEPG content and increased temperature favor chemisorption, contributing more than 90% when the pressure was lower than 0.4 MPa, while with increasing pressure, the physical contribution gradually increases up to 30%. This work evidences that [HDBU][IM]-DEPG is an excellent candidate for CO2 separation due to its high CO2 absorption capacity and low viscosity, and the high CO2 selectivity over CH4 and N2 expands its capability for real industrial applications.

Towards process, environment and economic based criteria for multi-objective optimization of industrial acid gas removal process

Acid gas removal is an important process to meet environmental regulations and protect machinery and pipelines. Non-dominated Sorting Genetic Algorithm-II (NSGA-II) is used to optimize the process considering economic and environmental objectives. The optimization was carried out using excel-based multi-objective optimization (EMOO). Acid gas removal process using dimethyl ethers of polyethylene glycol is optimized considering profit, global warming potential and Human Toxicity. At the same time, the amount of sulfide removed from the gas and that of methane gas recovered also need to be maximized. The trade-offs are investigated by reviewing the effects of the process variables on the objectives. Two-objective cases are considered and the Pareto optimal solutions are obtained. A comparison and a three-objective case was carried out. Two-objective optimization gave better results in all the cases but the three-objective solutions would be more practical, given that industries generally operate around more than two objectives.

Predictions of the vapor-liquid equilibrium data for low-GWP Hydrofluorocarbons + polyethylene-glycol dimethylether solvents by modified UNIFAC model

The working fluids are crucial for developing the absorption refrigeration system. Our previous work has proposed three novel working pairs, which uses the low-GWP HFCs (R32, R152a and R161) as the refrigerants and the polyethylene-glycol dimethylether solvent DMETEG as the absorbent. To explore the VLE behaviors of HFCs in other longer chain structures of polyethylene-glycol dimethylether solvents, the modified UNIFAC (Dortmund) model was applied for prediction. The previous binary parameters showed large deviations from the experimental data. Then the new binary parameters were obtained by regression. For R32+DMEDEG and R152a/R161+DMETrEG, the prediction ARAD results were reduced from 17.13%, 24.06% and 12.48% to 3.71%, 2.61% and 6.86%, respectively. Finally, the VLE data of R161 + PGDE at the temperatures of 293.15-343.15K were predicted.

Thermodynamics of acetaminophen and bovine serum albumin partitioning in ternary aqueous solutions comprising polyethylene glycol dimethyl ether 250 and choline bitartrate: Liquid-liquid equilibria, volumetric and acoustic investigations

The present work reports the biocompatible and nontoxic aqueous biphasic system, ABS, for acetaminophen and bovine serum albumin, BSA, separation. First, the binodal curves and tie-lines for {polyethylene glycol dimethyl ether 250 (PEGDME250) + choline bitartrate ([Ch][Bit]) + water} system was measured at different temperatures under atmospheric pressure (≈ 85 kPa). The phase separation in this ABS was studied by the salting-out coefficents obtained from tie-lines correaltion with setschenow equation. The results indicated that the biphasic region was enhanced by enhancing temperatre. The experimental data were fitted by two semi-empirical equations including Marchuk and Zafarani-Moattar equations for binodals and Othmer-Tobias, Bancroft, Osmotic virial equations, and e-or m-NRTL models for the tie-lines. Later, the performance of this ABS in acetaminophen and BSA partitioning was examined via calculation of partition coefficients and extraction efficiencies at different tie-lines and temperatures, the trend showed that the acetaminophen could be partitioned preferentially into the polymer-rich top phase with a single step extraction efficiency up to 80%, in where the BSA was effectively transferred into the [Ch][Bit]-rich bottom phase. In order to evaluate the driving-force for acetaminophen preferentially transferring to top phase, density and sound speed for systems (acetaminophen + PEGDME250 + water) and (acetaminophen + [Ch][Bit] + water) were determined at 298.15 K and the obtained results utilized for calculation the infinite molar volume and compressibility, and the transfer molar volume and compressibility. From density and sound speed results, it may be concluded that the favorable interactions between acetaminophen and PEGDME250 is responsible for preferentially acetaminophen transferring into top phase.

Partitioning behavior of caffeine, lamotrigine, clonazepam and oxcarbazepine in a biodegradable aqueous two-phase system comprising of polyethylene glycol dimethyl ether 250 and choline chloride/saccharose deep eutectic solvent

Aqueous two-phase systems (ATPSs) are well-known as novel, green, non-toxic and sensitive pharmaceutical pretreatment systems, where they are necessary for drug extraction from plasma, serum or urine samples. In the search for new ATPSs, especially those that exemplify the above-mentioned characteristics, here, a systematic investigation of biodegradable ATPS containing polyethylene glycol dimethyl ether 250 and one natural deep eutectic solvent obtained from mixtures of choline chloride as hydrogen bond acceptor (HBA) and saccharose as hydrogen bond donor (HBD) with different molar ratio (i.e. 1:1, 2:1 and 4:1) was made by liquid-liquid equilibria and drug partitioning studies at T = (298.15, 308.15 and 318.15) K under atmospheric pressure (≈85 kPa). The salting-out strength of the natural deep eutectic solvent calculated from fitting solubility data with the effective excluded volume theory was used to explore the influences of temperature and HBA:HBD molar ratio on the phase separation in this ATPS; the trend showed that the biphasic region was expanded by enhancing HBA:HBD molar ratio as well as increasing temperature. The performance of this ATPS for partitioning caffeine, lamotrigine, clonazepam and oxcarbazepine was evaluated by computing their partition coefficients and extraction efficiencies with focusing on the absence or presence of HBD, HBA:HBD molar ratio, temperature, drug nature and mass fractions of natural deep eutectic solvent. In all conditions, the high hydrophobic drugs could be partitioned effectively into the top phase with a single step extraction efficiency up to 90% indicating a preferential interaction between drug and polymer enriched in this phase.