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Zhou Y, Yang X, Bai L, Wu Z, Zhang J, Qin Z, Fan J. Investigation on the phase behaviors of aqueous surfactant two-phase systems containing Alkyl polyglucosides (APG) and alkyl polyglucoside sulfosuccinate (APGSS). J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Dai C, Liu P, Gao M, Liu Z, Liu C, Wu Y, Wang X, Liu S, Zhao M, Yan H. Preparation and thickening mechanism of copolymer fluorinated thickeners in supercritical CO2. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Shim Y. Computer simulation study of fluorocarbon phosphate surfactant based aqueous reverse micelle in supercritical CO 2: roles of surfactant functional groups, ionic strength, and phase changes in CO 2. Phys Chem Chem Phys 2020; 22:3434-3445. [PMID: 31984986 DOI: 10.1039/c9cp06613f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Structural and dynamic properties of an aqueous micelle organized from fluorocarbon phosphate surfactant molecules in supercritical carbon dioxide (CO2) are investigated via molecular dynamics computer simulations. The roles of the functional groups and ionic strength of the surfactants on the formation of reverse micelles in supercritical CO2, and related water dynamics characterized as translational and reorientational dynamics, are systematically demonstrated by employing three different phosphate-based surfactants paired with sodium cations. The strong electrostatic interactions between the phosphate head groups and sodium cations result in formation of an aqueous core inside the surfactant aggregates, where water molecules are bonded together with loss of the tetrahedral hydrogen bonded network found in bulk water. It is found that all the three surfactants with CO2-philic fluorocarbon double tails build up well-stabilized reverse micelles in supercritical CO2, avoiding direct contacts between CO2 and water molecules. Despite this, the surfactant with a carboxylic ester linkage between the phosphate head and fluorocarbon tail group tends to coordinate water molecules toward sustaining the inter-water hydrogen bonds, indicating better efficiency at covering the aqueous core with hydrophobic groups compared to one without a carboxylic ester group. As for water molecules confined in the reverse micelle, their translational and reorientational motions, and fluctuating dynamics of the inter-water hydrogen bonds, significantly slow down compared to bulk water at ambient temperature. The water dynamics become more restricted with an increase in ionic strength of the anionic surfactant; this is attributed to divalent surfactant heads and sodium cations being more tightly bound together with bonding to water compared to monovalent ones. Lastly, the structural and dynamic changes of the reverse micelle caused by a phase change in CO2 are monitored with gradually decreasing temperature and pressure from the supercritical to gaseous state for CO2. The average reverse micelle structure equilibrated in supercritical CO2 is found to remain stable over a time period of 0.2 ms through a depressurization process to gaseous CO2. We note that the diverse pathways of surfactant self-aggregation in gaseous CO2 could be controlled by the preceding solvation procedure in the supercritical regime which governs the final aggregated structures in gaseous CO2.
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Affiliation(s)
- Youngseon Shim
- CAE Group, Autonomous Material Development Laboratory, Samsung Advanced Institute of Technology, Samsung Electronics, Suwon, Gyeonggi 16678, Korea.
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Synthesis of triblock stabilizers with and without end-capped for dispersion polymerization in supercritical carbon dioxide. JOURNAL OF POLYMER RESEARCH 2019. [DOI: 10.1007/s10965-019-1891-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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5
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Azhar U, Yaqub R, Geng B, Zhang S. Data set on stability comparison of emulsions stabilized by cationic fluorosurfactant against conventional surfactants and high thermal performance of fluoropolymer foams. Data Brief 2017; 13:396-400. [PMID: 28664176 PMCID: PMC5480818 DOI: 10.1016/j.dib.2017.06.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 05/23/2017] [Accepted: 06/01/2017] [Indexed: 11/17/2022] Open
Abstract
This data article includes emulsion stability comparison of cationic fluorosurfactant (CFS) against conventional surfactants. Span 80, Hypermer, Tween 80 and CTAB were used as conventional emulsifiers and only after 30 minutes bilayer phase separation observed in emulsions prepared by Tween 80 while CTAB failed to give fluoroemulsion, as compared to the CFS stabilized fluoro-HIPE which demonstrated superb stabilization of more than 72 h without phase separation. Thermal stability of Poly(hexafluorobutyl acrylate)-Divinyl benzene (PHFBA-DVB) was compared with porous polymer prepared by the same concentration of CFS 9 wt% by using trifluoroethyl methacrylate (TFEMA) as monomer phase. Results of PFP prepared with HFBA showed remarkable stability performance at more than 340.69 °C while porous polymer synthesized by TFEMA started to decompose even at 237.36 °C. The main findings based on the data presented here are reported in the paper "A cationicfluorosurfactant for fabrication of high-performance fluoropolymer foams with controllable morphology" (Azhar et al., 2017) [1].
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Affiliation(s)
- Umair Azhar
- Shandong Provincial Key Laboratory of Fluorine Chemistry and Chemical Materials, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China
- Department of Chemistry, University of Gujrat, Gujrat, Pakistan
| | - Rimsha Yaqub
- Shandong Provincial Key Laboratory of Fluorine Chemistry and Chemical Materials, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China
- Department of Chemistry, University of Gujrat, Gujrat, Pakistan
| | - Bing Geng
- Shandong Provincial Key Laboratory of Fluorine Chemistry and Chemical Materials, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China
- Department of Chemistry, University of Gujrat, Gujrat, Pakistan
| | - Shuxiang Zhang
- Shandong Provincial Key Laboratory of Fluorine Chemistry and Chemical Materials, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China
- Department of Chemistry, University of Gujrat, Gujrat, Pakistan
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Liu B, Tang X, Fang W, Li X, Zhang J, Zhang Z, Shen Y, Yan Y, Sun X, He J. Molecular dynamics study of di-CF4 based reverse micelles in supercritical CO 2. Phys Chem Chem Phys 2016; 18:29156-29163. [PMID: 27730238 DOI: 10.1039/c6cp04253h] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Reverse micelles (RMs) in supercritical CO2 (scCO2) are promising alternatives for organic solvents, especially when both polar and non-polar components are involved. Fluorinated surfactants, particularly double-chain fluorocarbon surfactants, are able to form well-structured RMs in scCO2. The inherent self-assembly mechanisms of surfactants in scCO2 are still subject to discussion. In this study, molecular dynamics simulations are performed to investigate the self-aggregation behavior of di-CF4 based RMs in scCO2, and stable and spherical RMs are formed. The dynamics process and the self-assembly structure in the RMs reveal a three-step mechanism to form the RMs, that is, small RMs, rod-like RMs and fusion of the rod-like RMs. Hydrogen-bonds between headgroups and water molecules, and salt bridges linking Na+ ions, headgroups and water molecules enhance the interfacial packing efficiency of the surfactant. The results show that di-CF4 molecules have a high surfactant coverage at the RM interface, implying a high CO2-philicity. This mainly results from bending of the short chain (C-COO-CH2-(CF2)3-CF3) due to the flexible carboxyl group. The microscopic insight provided in this study is helpful in understanding surfactant self-assembly phenomena and designing new CO2-philic surfactants.
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Affiliation(s)
- Bing Liu
- School of Science, China University of Petroleum, Qingdao 266580, Shandong, China. and NTNU Nanomechanical Lab, Department of Structural Engineering, Norwegian University of Science and Technology (NTNU), Trondheim, 7491, Norway.
| | - Xinpeng Tang
- School of Science, China University of Petroleum, Qingdao 266580, Shandong, China.
| | - Wenjing Fang
- School of Science, China University of Petroleum, Qingdao 266580, Shandong, China.
| | - Xiaoqi Li
- School of Science, China University of Petroleum, Qingdao 266580, Shandong, China.
| | - Jun Zhang
- School of Science, China University of Petroleum, Qingdao 266580, Shandong, China.
| | - Zhiliang Zhang
- NTNU Nanomechanical Lab, Department of Structural Engineering, Norwegian University of Science and Technology (NTNU), Trondheim, 7491, Norway.
| | - Yue Shen
- School of Science, China University of Petroleum, Qingdao 266580, Shandong, China.
| | - Youguo Yan
- School of Science, China University of Petroleum, Qingdao 266580, Shandong, China.
| | - Xiaoli Sun
- School of Science, China University of Petroleum, Qingdao 266580, Shandong, China.
| | - Jianying He
- NTNU Nanomechanical Lab, Department of Structural Engineering, Norwegian University of Science and Technology (NTNU), Trondheim, 7491, Norway.
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