1
|
Kurapati R, Natarajan U. Complex role of chemical nature and tacticity in the adsorption free energy of carboxylic acid polymers at the oil-water interface: molecular dynamics simulations. Phys Chem Chem Phys 2023; 25:27783-27797. [PMID: 37814803 DOI: 10.1039/d3cp02754f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/11/2023]
Abstract
Scientific understanding of the molecular structure and adsorption of polymers at oil-water liquid interfaces is very limited. In this study the adsorption free energy at the oil (CCl4)-water interface was estimated using umbrella sampling molecular dynamics simulations for six carboxylate type vinyl polymers differing in hydrophobic nature and tacticity: isotactic and syndiotactic poly(acrylic acid) (i-PAA, s-PAA), isotactic and syndiotactic poly(methacrylic acid) (i-PMA, s-PMA), and atactic and syndiotactic poly(ethylacrylic acid) (a-PEA, s-PEA). ΔGads values are in the order i-PMA < a-PEA < s-PEA < s-PAA < i-PAA < s-PMA. The results show the significant and complex influence of the chemical nature as well as tacticity of the polymer on its adsorption free energy as related to hydrogen bonding and orientation of bonds with respect to oil and water phases. The influence of tacticity is found to be the highest for PMA, which is interpreted to occur due to the balance between interactions among side groups and those occurring between side groups and solvent. Interactions between side-groups are crucial for determining the conformation of PAA (most hydrophilic) and the solvation of the side-group in water is crucial for determining the conformation of PEA (most hydrophobic). The adsorption of PMA represents the transition between these two dominating effects. The molecular contributions to the enthalpy of adsorption indicate that adsorption is favored mainly through two interactions: polymer-CCl4 and water-water.
Collapse
Affiliation(s)
- Raviteja Kurapati
- Macromolecular Modeling and Simulation Laboratory, Department of Chemical Engineering, Indian Institute of Technology (IIT) Madras, Chennai, 600036, India.
| | - Upendra Natarajan
- Macromolecular Modeling and Simulation Laboratory, Department of Chemical Engineering, Indian Institute of Technology (IIT) Madras, Chennai, 600036, India.
| |
Collapse
|
2
|
Philip J. Magnetic nanofluids (Ferrofluids): Recent advances, applications, challenges, and future directions. Adv Colloid Interface Sci 2023; 311:102810. [PMID: 36417827 DOI: 10.1016/j.cis.2022.102810] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 10/28/2022] [Accepted: 11/05/2022] [Indexed: 11/16/2022]
Abstract
Impelled by the need to find solutions to new challenges of modern technologies new materials with unique properties are being explored. Among various new materials that emerged over the decades, magnetic fluids exhibiting interesting physiochemical properties (optical, thermal, magnetic, rheological, apparent density, etc.) under a magnetic stimulus have been at the forefront of research. In the initial phase, there has been a fervent scientific curiosity to understand the field-induced intriguing properties of such fluids but later a plethora of technological applications emerged. Magnetic nanofluid, popularly known as ferrofluid, is a colloidal suspension of fine magnetic nanoparticles, has been at the forefront of research because of its magnetically tunable physicochemical properties and applications. Due to their stimuli-responsive behaviour, they have been finding more applications in biology and other engineering disciplines in recent years. Therefore, a critical review of this topic highlighting the necessary background, the potential of this material for emerging technologies, and the latest developments is warranted. This review also provides a summary of various applications, along with the key challenges and future research directions. The first part of the review addresses the different types of magnetic fluids, the genesis of magnetic fluids, their synthesis methodologies, properties, and stabilization techniques are discussed in detail. The second part of the review highlights the applications of magnetic nanofluids and nanoemulsions (as model systems) in probing order-disorder transitions, scattering, diffraction, magnetically reconfigurable internal structures, molecular interaction, and weak forces between colloidal particles, conformational changes of macromolecules at interfaces and polymer-surfactant complexation at the oil-water interface. The last part of the review summarizes the interesting applications of magnetic fluids such as heat transfer, sensors (temperature, pH, urea detection, cations, defect detection sensors), tunable optical filters, removal of dyes, dynamic seals, magnetic hyperthermia-based cancer therapy and other biomedical applications. The applications of magnetic nanofluids in diverse disciplines are growing day by day, yet there are challenges in their practical adaptation as field-worthy or packaged products. This review provides a pedagogical description of magnetic fluids, with the necessary background, key concepts, physics, experimental protocols, design of experiments, challenges and future directions.
Collapse
Affiliation(s)
- John Philip
- Smart Materials Section, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, India.
| |
Collapse
|
3
|
Kurapati R, Natarajan U. Tacticity and Ionization Effects on Adsorption Behavior of Poly(acrylic acid) and Poly(methacrylic acid) at the CCl 4–H 2O Interface Revealed by MD Simulations. Ind Eng Chem Res 2022. [DOI: 10.1021/acs.iecr.2c02416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Raviteja Kurapati
- Macromolecular Modeling and Simulation Laboratory, Department of Chemical Engineering, Indian Institute of Technology (IIT) Madras, Chennai600036, India
| | - Upendra Natarajan
- Macromolecular Modeling and Simulation Laboratory, Department of Chemical Engineering, Indian Institute of Technology (IIT) Madras, Chennai600036, India
| |
Collapse
|
4
|
Ma B, Yao J, Chen Z, Liu B, Kim J, Zhao C, Zhu X, Mihucz VG, Minkina T, Knudsen TŠ. Superior elimination of Cr(VI) using polydopamine functionalized attapulgite supported nZVI composite: Behavior and mechanism. CHEMOSPHERE 2022; 287:131970. [PMID: 34450370 DOI: 10.1016/j.chemosphere.2021.131970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 08/11/2021] [Accepted: 08/19/2021] [Indexed: 06/13/2023]
Abstract
In this study, a polydopamine (PDA) modified attapulgite (ATP) supported nano sized zero-valent iron (nZVI) composite (PDA/ATP-nZVI) was rapidly synthesized under acidic conditions, and employed to alleviate Cr(VI) toxicity from an aqueous solution. Kinetic studies revealed that Cr(VI) adsorption process followed the pseudo-second order model, suggesting chemisorption was the dominant adsorption mechanism. Liu isotherm adsorption model was able to better describe the Cr(VI) adsorption isotherm with the maximum adsorption capacity of 134.05 mg/g. The thermodynamic study demonstrated that the adsorption process occurred spontaneously, accompanied by the increase in entropy and endothermic reaction. Low concentrations of coexisting ions had negligible effects on the removal of Cr(VI), while high concentrations of interfering ions were able to facilitate the removal of Cr(VI). Reactive species test revealed that Fe2+ played a key role in Cr(VI) reduction by PDA/ATP-nZVI. PDA enhanced the elimination of Cr(VI) via donation of electrons to Cr(VI) and acceleration of Fe3+ transformation to Fe2+. Furthermore, PDA was able to effectively inhibit the leaching of iron species and generation of ferric hydroxide sludge. Mechanistic study revealed that 72% of Cr(VI) elimination was attributed to reduction/precipitation, while 28% of Cr(VI) elimination was due to the surface adsorption.
Collapse
Affiliation(s)
- Bo Ma
- School of Water Resources and Environment and Research Center of Environmental Science and Engineering, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083, China.
| | - Jun Yao
- School of Water Resources and Environment and Research Center of Environmental Science and Engineering, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083, China.
| | - Zhihui Chen
- School of Water Resources and Environment and Research Center of Environmental Science and Engineering, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083, China
| | - Bang Liu
- School of Water Resources and Environment and Research Center of Environmental Science and Engineering, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083, China
| | - Jonghyok Kim
- School of Water Resources and Environment and Research Center of Environmental Science and Engineering, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083, China; Department of Energy Science, Kim Il Sung University, Pyongyang, 950003, Democratic People's Republic of Korea
| | - Chenchen Zhao
- School of Water Resources and Environment and Research Center of Environmental Science and Engineering, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083, China
| | - Xiaozhe Zhu
- School of Water Resources and Environment and Research Center of Environmental Science and Engineering, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083, China
| | - Victor G Mihucz
- Sino-Hungarian Joint Research Laboratory for Environmental Sciences and Health, Eötvös Loránd University, H-1117 Budapest, Pázmány Péter stny. 1/A, Hungary
| | - Tatiana Minkina
- Southern Federal University, Rostov-on-Don, 344090, Russian Federation
| | - Tatjana Šolević Knudsen
- University of Belgrade, Institute of Chemistry, Technology and Metallurgy, Department of Chemistry, Njegoševa 12, 11000, Belgrade, Serbia
| |
Collapse
|
5
|
Gordievskaya YD, Kramarenko EY, Gavrilov AA. The effect of explicit polarity on the conformational behavior of a single polyelectrolyte chain. Phys Chem Chem Phys 2021; 23:26296-26305. [PMID: 34787619 DOI: 10.1039/d1cp03167h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In this work using dissipative particle dynamics simulations with explicit treatment of polar species we demonstrate that the molecular nature of dielectric media has a significant impact on swelling and collapse of a polyelectrolyte chain in a dilute solution. We show that the small-scale effects related to the presence of polar species lead to the intensification of the electrostatic interactions when the charges are close to each other and/or their density is high enough. As a result, the electrostatic strength , usually regarded as the main parameter governing the polyelectrolyte chain collapse, does not have a universal meaning: the value of λ at which the coil-to-globule transition occurs is found to be dependent on the specific fixed value of the solvent bulk permittivity ε while varying the monomer unit charge Q and vice versa. This effect is observed even when the backbone and the counterions have the same polarity as the solvent beads, i.e. no dielectric mismatch is present. The reason for such behavior is rationalized in terms of the "effective" dielectric permittivity εeff which depends on the volume fraction φ of charged units inside the polymer chain volume; using εeff instead of ε collapses all data onto one master curve describing the chain shrinking with λ. Furthermore, it is shown that a polar chain adopts less swollen conformations in the polyelectrolyte regime and collapses more easily compared to a non-polar chain.
Collapse
Affiliation(s)
- Yulia D Gordievskaya
- Faculty of Physics, Lomonosov Moscow State University, 119991 Moscow, Russia. .,A. N. Nesmeyanov Institute of Organoelement Compounds RAS, 119991 Moscow, Russia
| | - Elena Yu Kramarenko
- Faculty of Physics, Lomonosov Moscow State University, 119991 Moscow, Russia. .,A. N. Nesmeyanov Institute of Organoelement Compounds RAS, 119991 Moscow, Russia
| | - Alexey A Gavrilov
- Faculty of Physics, Lomonosov Moscow State University, 119991 Moscow, Russia.
| |
Collapse
|
6
|
Nandy M, Lahiri BB, Philip J. Inter-droplet force between magnetically polarizable Pickering oil-in-water nanoemulsions stabilized with γ-Al 2O 3 nanoparticles: Role of electrostatic and electric dipolar interactions. J Colloid Interface Sci 2021; 607:1671-1686. [PMID: 34592554 DOI: 10.1016/j.jcis.2021.09.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 09/03/2021] [Accepted: 09/04/2021] [Indexed: 12/30/2022]
Abstract
HYPOTHESIS The presence of nanoparticles at oil-water interface influences the interaction forces between Pickering emulsions. When charged nanoparticles are at the oil-water interface of an electrostatically stabilized emulsion, in addition to the screened Coulombic interaction, electric dipolar force also influences the total inter-droplet force profiles. An in-depth understanding of the effects of such electric dipolar forces is essential for designing colloidally stable Pickering nanoemulsions for various applications. EXPERIMENTS Inter-droplet forces between γ-Al2O3 nanoparticle stabilized oil-in-water nanoemulsion, containing superparamagnetic nanoparticles (magnetically polarizable) in the oil phase, are measured using the magnetic-chaining technique at different pH and salt concentrations. The role of mono-, di- and tri-valent salts on the inter-droplet force profiles are assessed. FINDINGS Force measurement studies reveal a lowering of inter-droplet spacing, within the linear chains, for higher salt concentrations due to an increased screening. Strong interfacial attachment of the charged nanoparticles results in the formation of an asymmetric charge cloud leading to an electric dipolar interaction. Incorporating the contributions of electric dipolar and screened Coulombic interactions, the theoretically estimated total repulsive force magnitudes are in good agreement with the experimental data. The obtained results offer better insights into the nature of colloidal force between charged particle stabilized nanoemulsions.
Collapse
Affiliation(s)
- Manali Nandy
- Smart Materials Section, Corrosion Science and Technology Division, Materials Characterization Group, Metallurgy and Materials Group, HBNI, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu 603102, India
| | - B B Lahiri
- Smart Materials Section, Corrosion Science and Technology Division, Materials Characterization Group, Metallurgy and Materials Group, HBNI, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu 603102, India.
| | - John Philip
- Smart Materials Section, Corrosion Science and Technology Division, Materials Characterization Group, Metallurgy and Materials Group, HBNI, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu 603102, India
| |
Collapse
|
7
|
Poly acrylic acid stabilized magnetic nanoemulsions for visual defect detection: Effect of pH on detection sensitivity and colloidal stability. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116332] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
8
|
Zhou S. Effective electrostatic forces between two neutral surfaces with atomic scale strip shape surface charge separation. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.113272] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
|
9
|
Ranoo S, Lahiri BB, Nandy M, Philip J. Enhanced magnetic heating efficiency at acidic pH for magnetic nanoemulsions stabilized with a weak polyelectrolyte. J Colloid Interface Sci 2020; 579:582-597. [PMID: 32623124 DOI: 10.1016/j.jcis.2020.06.093] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/08/2020] [Accepted: 06/22/2020] [Indexed: 02/02/2023]
Abstract
HYPOTHESIS Magnetic fluid hyperthermia has attracted considerable attention for cancer therapeutics. Magnetic nanoemulsions are potential candidates for multi-modal hyperthermia due to the possibility of volumetric loading with suitable chemo/photo-therapy agents. Often, the nanocarriers are stabilized using organic molecules that behave differently under varying pH and hence, an understanding of their interfacial behaviour is important for practical applications. EXPERIMENTS We probe the magnetic heating efficiency of poly acrylic acid (PAA) stabilized oil-in-water magnetic nanoemulsions, as a function of pH, where the conformational changes of the PAA molecules are studied using dynamic light scattering and inter-droplet force measurements. FINDINGS A ~50% enhanced heating efficiency is observed when solution pH is reduced from ~9 to 3, which is attributed to the coil-to-globule conformational changes of the PAA molecules. The increased ionization of the carboxylic acid groups, at higher pH, leads to reduced hydrophobicity that results in an increase in the interfacial thermal resistance causing a lower magneto-thermal heating efficiency at higher pH. The proposed interfacial heat transfer hypothesis is experimentally verified using thermal imaging, where a lower rate of heat transfer is obtained at higher pH. The observed enhanced hyperthermia efficiency at low pH is beneficial for designing efficient pH-responsive nano-carriers for multi-modal hyperthermia.
Collapse
Affiliation(s)
- Surojit Ranoo
- Smart Materials Section, Corrosion Science and Technology Division, Materials Characterization Group, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, HBNI, Kalpakkam, Tamil Nadu 603102, India
| | - B B Lahiri
- Smart Materials Section, Corrosion Science and Technology Division, Materials Characterization Group, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, HBNI, Kalpakkam, Tamil Nadu 603102, India.
| | - Manali Nandy
- Smart Materials Section, Corrosion Science and Technology Division, Materials Characterization Group, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, HBNI, Kalpakkam, Tamil Nadu 603102, India
| | - John Philip
- Smart Materials Section, Corrosion Science and Technology Division, Materials Characterization Group, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, HBNI, Kalpakkam, Tamil Nadu 603102, India.
| |
Collapse
|
10
|
Wang H, Wang Z, Yue R, Gao F, Ren R, Wei J, Wang X, Kong Z. Functional group-rich hyperbranched magnetic material for simultaneous efficient removal of heavy metal ions from aqueous solution. JOURNAL OF HAZARDOUS MATERIALS 2020; 384:121288. [PMID: 31581011 DOI: 10.1016/j.jhazmat.2019.121288] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 09/06/2019] [Accepted: 09/22/2019] [Indexed: 06/10/2023]
Abstract
In order to achieve the purpose of simultaneous removal of coexisting heavy metal ions, in this work, functionalized magnetic mesoprous nanomaterials (Fe3O4-HBPA-ASA) with high density and multiple adsorption sites were designed and prepared. The obtained Fe3O4-HBPA-ASA was characterized by SEM, FTIR, VSM, TGA and zeta potential. Cu(II), Pb(II) and Cd(II) were chosen as the model heavy metal ions, the adsorption experiments showed that Fe3O4-HBPA-ASA showed hightheoretical adsorption capacitiesin individual system, and the maximum adsorption capacity was 136.66 mg/g, 88.36 mg/g and 165.46 mg/g, respectively. In the binary and ternary systems, the competitive adsorption leads to a decrease in the adsorption capacity of Cu(II), Pb(II) and Cd(II). However, in the ternary system with a concentration lower than 15 mg/L, the simultaneous removal rate was still higher than 90%. The adsorption isotherms and kineticswere well fitted by Langmuir and pseudo-second-order models, respectively. The XPS and density functional theory (DFT) analysis have confirmed that the adsorption of metal ions was related to various types of functional groups on the surface of Fe3O4-HBPA-ASA, while the adsorption mechanisms of Cu(II), Cd(II) and Pb(II) were different.
Collapse
Affiliation(s)
- Huicai Wang
- School of Chemistry and Chemical Engineering, Tiangong University, Tianjin, 300387, China; State Key Laboratory of Separation Membranes and Membrane Processes, Tiangong University, Tianjin, 300387, China.
| | - Zhenwen Wang
- School of Environmental Science and Engineering, Tiangong University, Tianjin, 300387, China; State Key Laboratory of Separation Membranes and Membrane Processes, Tiangong University, Tianjin, 300387, China
| | - Ruirui Yue
- School of Chemistry and Chemical Engineering, Tiangong University, Tianjin, 300387, China; State Key Laboratory of Separation Membranes and Membrane Processes, Tiangong University, Tianjin, 300387, China
| | - Feng Gao
- School of Environmental Science and Engineering, Tiangong University, Tianjin, 300387, China; State Key Laboratory of Separation Membranes and Membrane Processes, Tiangong University, Tianjin, 300387, China
| | - Ruili Ren
- School of Chemistry and Chemical Engineering, Tiangong University, Tianjin, 300387, China; State Key Laboratory of Separation Membranes and Membrane Processes, Tiangong University, Tianjin, 300387, China
| | - Junfu Wei
- School of Chemistry and Chemical Engineering, Tiangong University, Tianjin, 300387, China; State Key Laboratory of Separation Membranes and Membrane Processes, Tiangong University, Tianjin, 300387, China
| | - Xiaolei Wang
- School of Environmental Science and Engineering, Tiangong University, Tianjin, 300387, China; State Key Laboratory of Separation Membranes and Membrane Processes, Tiangong University, Tianjin, 300387, China
| | - Zhiyun Kong
- School of Environmental Science and Engineering, Tiangong University, Tianjin, 300387, China; State Key Laboratory of Separation Membranes and Membrane Processes, Tiangong University, Tianjin, 300387, China
| |
Collapse
|
11
|
Kyrychenko A, Blazhynska MM, Slavgorodska MV, Kalugin ON. Stimuli-responsive adsorption of poly(acrylic acid) onto silver nanoparticles: Role of polymer chain length and degree of ionization. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2018.11.130] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|