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Preparation and Characterization of Polyvinylalcohol/Polysulfone Composite Membranes for Enhanced CO 2/N 2 Separation. Polymers (Basel) 2022; 15:polym15010124. [PMID: 36616476 PMCID: PMC9823891 DOI: 10.3390/polym15010124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 12/23/2022] [Accepted: 12/23/2022] [Indexed: 12/29/2022] Open
Abstract
The unique properties of polyvinyl alcohol (PVA) and polysulfone (PSf), such as good membrane-forming ability and adjustable structure, provide a great opportunity for CO2-separation membrane development. This work focuses on the fabrication of PVA/PSf composite membranes for CO2/N2 separations. The membranes prepared by coating a 7.5 wt% PVA on top of PSf substrate showed a relatively thin selective layer of 1.7 µm with an enhanced CO2/N2 selectivity of 78, which is a ca. 200% increase compared to the pure PSf membranes. The CO2/N2 selectivity decreases at a rapid rate with the increase of feed pressure from 1.8 to 5 bar, while the CO2 permeance shows a slight reduction, which is caused by the weakening of coupling transportation between water and CO2 molecules, as well as membrane compaction at higher pressures. Increasing operating temperature from 22 °C to 50 °C leads to a slight decrease in CO2 permeance, but a significant reduction in the CO2/N2 selectivity from 78 to 27.1. Moreover, the mass transfer coefficient of gas molecules is expected to increase at a higher velocity, which leads to the increase of CO2 permeance at higher feed flow rates. It was concluded that the CO2 separation performance of the prepared membranes was significantly dependent on the membrane operating parameters, and process design and optimization are crucial to bringing CO2-separation membranes for industrial applications in post-combustion carbon capture.
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Mirzamani M, Flickinger M, Kharb S, Jones RL, Ananthapadmanabhan K, Smith E, Kumari H. Investigating the Effect of Dipropylene glycol and Mixed-surfactant Concentrations on Perfume Release. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.129508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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3
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Lin F, Qi Q, Zhang J, Zhou W, Zhang J, Fu P, Zhang X, Qiao X, Liu M, Pang X, Cui Z. From Unimolecular Template to Silver Nanocrystal Clusters: An Effective Strategy to Balance Antibacterial Activity and Cytotoxicity. ACS APPLIED MATERIALS & INTERFACES 2021; 13:39806-39818. [PMID: 34387459 DOI: 10.1021/acsami.1c07986] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Silver nanomaterials have attracted a great deal of interest due to their broad-spectrum antimicrobial activity. However, it is still challenging to balance the high antibacterial efficiency with low damage to biological cells of silver nanostructures, especially when the diameter decreases to less than 10 nm. Here, we developed a new type of Ag nanohybrid material via a unimolecular micelle template method, which presents amazing antibacterial activities and almost noncytotoxicity. First, water-soluble multiarm star-shaped brushlike copolymer α-CD-g-[(PEO40-g-PAA50)-b-PEO5]18 was precisely synthesized and its micelle behavior in different solvents was revealed. Then, nanocrystal clusters assembled by Ag grains (Ag@Template NCs) were prepared through an in situ redox route using the unimolecular micelle of α-CD-g-[(PEO40-g-PAA50)-b-PEO5]18 as the soft template, AgNO3 as a precursor, and tetrabutylammonium borohydride (TBAB) as the reducing agent. The overall size of the achieved Ag@Template NCs is controlled by the template structure at around 40 nm (Dh in DMF), and the size of the Ag grain can be easily regulated from ∼1 to ∼5 nm by adjusting the feeding ratio of AgNO3/acrylic acid (AA) units in the template from 1:10 to 1:1. Benefitting from the structural design of the template, all Ag@Template NCs prepared here exhibit excellent dispersibility and chemical stability in different aqueous environments (neutral, pH = 5.5, and 0.9% NaCl physiological saline solution), which play a crucial role in the long-term storage and potential application in a complex physiological environment. The antibacterial and cytotoxicity tests indicate that Ag@Template NCs display much better performance than Ag nanoparticles (Ag NPs), which have a comparable overall size of ∼25 nm. The inhibitory capability of Ag@Template NCs to bacteria strongly depends on the grain size. Specifically, the Ag@Template-1 NC assembled by the smallest grains (1.6 ± 0.3 nm) presents the best antibacterial activity. For E. coli (-), the MIC value is as low as 5 μg/mL (0.36 μg/mL of Ag), while for S. aureus (+), the value is around 10 μg/mL (0.72 μg/mL of Ag). The survival rate of L02 cells and lactate dehydrogenase assay together illustrate the low cytotoxicity possessed by the prepared Ag@Template NCs. Therefore, the proposed Ag@Template NC structure successfully resolves the high reactivity, instability, and fast oxidation issues of the ultrasmall Ag nanoparticles, and integrates high antibacterial efficiency and nontoxicity to biological cells into one platform, which implies its broad potential application in biomedicine.
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Affiliation(s)
- Fangke Lin
- School of Materials Science and Engineering, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China
| | - Qianqian Qi
- School of Materials Science and Engineering, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China
| | - Junle Zhang
- School of Materials Science and Engineering, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China
| | - Wenjun Zhou
- School of Materials Science and Engineering, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China
| | - Jiahui Zhang
- School of Materials Science and Engineering, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China
| | - Peng Fu
- School of Materials Science and Engineering, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China
| | - Xiaomeng Zhang
- School of Materials Science and Engineering, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China
| | - Xiaoguang Qiao
- School of Materials Science and Engineering, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China
| | - Minying Liu
- School of Materials Science and Engineering, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China
| | - Xinchang Pang
- School of Materials Science and Engineering, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China
| | - Zhe Cui
- School of Materials Science and Engineering, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou 450001, China
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Effect of solvent on surfactant adsorption kinetics: Dibutyl phthalate in aqueous MeOH solvents. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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5
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MacDonald S, MacLennan S, Marangoni DG. Calorimetric determination of the thermodynamics of alcohol-surfactant mixed micelle formation: Temperature and concentration effects. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.112531] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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6
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Chen S. Conformation and solubility of poly(ethylene oxide) in polymer-surfactant complex at high-temperature and high-salinity conditions. Colloids Surf A Physicochem Eng Asp 2019. [DOI: 10.1016/j.colsurfa.2019.123811] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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7
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Khan H, Seddon JM, Law RV, Brooks NJ, Robles E, Cabral JT, Ces O. Effect of glycerol with sodium chloride on the Krafft point of sodium dodecyl sulfate using surface tension. J Colloid Interface Sci 2019; 538:75-82. [DOI: 10.1016/j.jcis.2018.11.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 11/02/2018] [Accepted: 11/07/2018] [Indexed: 10/27/2022]
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8
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Jiang H, Beaucage G, Vogtt K, Weaver M. The effect of solvent polarity on wormlike micelles using dipropylene glycol (DPG) as a cosolvent in an anionic/zwitterionic mixed surfactant system. J Colloid Interface Sci 2017; 509:25-31. [PMID: 28881202 DOI: 10.1016/j.jcis.2017.08.090] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Revised: 08/27/2017] [Accepted: 08/28/2017] [Indexed: 11/26/2022]
Abstract
HYPOTHESIS The behavior/properties of micellar solutions are governed by Coulombic interactions that are influenced by the polarity of the surfactant head groups, hydrophobic tails, and solvent molecules. The addition of co-solvent should have a direct impact on solvent polarity and the size of the micelles are expected to decrease accordingly. EXPERIMENTS In this study, a mixed surfactant system is studied composed of a common anionic surfactant, sodium laureth sulfate-1, modified by a zwitterionic surfactant, cocamidopropyl betaine in deuterated water. In this system, worm-like micelles (WLMs) are formed. The influence of a co-solvent, dipropylene glycol (DPG) in the present of high salt content, is investigated. DPG primarily modifies the dielectric constant of the solvent. FINDINGS It was found that the addition of DPG slightly decreased the micelle radius, but dramatically reduced the persistence length as well as the contour length of the micelles. The relative dependence of contour length on salt concentration is not significantly changed. Thus, it is shown that the self-assembled structure can be tuned by adjusting solvent polarity without affecting the relative tunability of the WLM/ellipsoidal structure through counter ion concentration.
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Affiliation(s)
- Hanqiu Jiang
- Department of Chemical and Materials Engineering, University of Cincinnati, Cincinnati, OH 45221-0012, United States
| | - Gregory Beaucage
- Department of Chemical and Materials Engineering, University of Cincinnati, Cincinnati, OH 45221-0012, United States.
| | - Karsten Vogtt
- Department of Chemical and Materials Engineering, University of Cincinnati, Cincinnati, OH 45221-0012, United States
| | - Michael Weaver
- P&G Analytical Sciences, 8700 Mason-Montgomery Rd, Mason, OH 45040, United States
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Ferreira GMD, Ferreira GMD, Agudelo ÁJP, Hespanhol da Silva MC, Rezende JDP, Pires ACDS, da Silva LHM. Effect of 1-Butyl-3-methylimidazolium Halide on the Relative Stability between Sodium Dodecyl Sulfate Micelles and Sodium Dodecyl Sulfate–Poly(ethylene oxide) Nanoaggregates. J Phys Chem B 2015; 119:15758-68. [DOI: 10.1021/acs.jpcb.5b09819] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gabriel M. Dias Ferreira
- Grupo de Química Verde
Coloidal e Macromolecular, Departamento de Química, Centro
de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa (UFV), Av. P. H. Rolfs s/n, Viçosa, MG 36570900,
Brasil
| | - Guilherme M. Dias Ferreira
- Grupo de Química Verde
Coloidal e Macromolecular, Departamento de Química, Centro
de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa (UFV), Av. P. H. Rolfs s/n, Viçosa, MG 36570900,
Brasil
| | - Álvaro J. Patiño Agudelo
- Grupo de Química Verde
Coloidal e Macromolecular, Departamento de Química, Centro
de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa (UFV), Av. P. H. Rolfs s/n, Viçosa, MG 36570900,
Brasil
| | - Maria C. Hespanhol da Silva
- Grupo de Química Verde
Coloidal e Macromolecular, Departamento de Química, Centro
de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa (UFV), Av. P. H. Rolfs s/n, Viçosa, MG 36570900,
Brasil
| | - Jaqueline de Paula Rezende
- Grupo de Química Verde
Coloidal e Macromolecular, Departamento de Química, Centro
de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa (UFV), Av. P. H. Rolfs s/n, Viçosa, MG 36570900,
Brasil
| | - Ana Clarissa dos Santos Pires
- Grupo de Química Verde
Coloidal e Macromolecular, Departamento de Química, Centro
de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa (UFV), Av. P. H. Rolfs s/n, Viçosa, MG 36570900,
Brasil
| | - Luis Henrique Mendes da Silva
- Grupo de Química Verde
Coloidal e Macromolecular, Departamento de Química, Centro
de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa (UFV), Av. P. H. Rolfs s/n, Viçosa, MG 36570900,
Brasil
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Fajalia AI, Tsianou M. Charging and uncharging a neutral polymer in solution: a small-angle neutron scattering investigation. J Phys Chem B 2014; 118:10725-39. [PMID: 25014246 DOI: 10.1021/jp5023168] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Aqueous formulations containing polymers and surfactants find several applications in pharmaceutics, coatings, inks, and home products. The association between polymers and surfactants contributes greatly to the function of these complex fluids, however, the effects of polar organic solvents, ubiquitous in formulations, remain mostly unexplored. We have analyzed small angle neutron scattering (SANS) data to determine the conformation of a "model" nonionic polymer, poly(ethylene oxide) (PEO), in aqueous solutions as affected by the presence of an ionic surfactant, sodium dodecyl sulfate (SDS), and subsequent addition of short-chain alcohol (ethanol or 2-propanol). PEO chains (MW = 90,000) are Gaussian in dilute aqueous solutions, but become polyelectrolyte-like upon the addition of 30 mM SDS, with about 6 SDS micelles bound to each PEO chain. Micelles associated with polymer are similar in structure and interactions to micelles that form in aqueous solutions in the absence of polymer. Addition of alcohol alters both the polymer and micelle structure and interactions, leads to detachment of micelles from the polymer, and the PEO chains regain their Gaussian conformation. 2-Propanol is more effective than ethanol in influencing the polymer conformation and the properties of SDS micelles in aqueous solutions, either in the presence or in the absence of PEO. This study contributes fundamental insights on polymer and surfactant organization in solution, as well as new, quantitative information on systems that are widely used in practice.
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Affiliation(s)
- Ankitkumar I Fajalia
- Department of Chemical & Biological Engineering, University at Buffalo, The State University of New York (SUNY) , Buffalo, New York 14260-4200, United States
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11
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Influence of aquo-organic solvent media on the self-aggregation of sodium dodecyl sulfate (SDS) and its interaction with polyvinylpyrrolidone (PVP). Colloid Polym Sci 2014. [DOI: 10.1007/s00396-014-3273-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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12
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Peng B, Han X, Liu H, Tam KC. Binding of cationic surfactants to a thermo-sensitive copolymer below and above its cloud point. J Colloid Interface Sci 2013; 412:17-23. [DOI: 10.1016/j.jcis.2013.09.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 08/29/2013] [Accepted: 09/03/2013] [Indexed: 12/14/2022]
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13
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Pan A, Naskar B, Prameela GKS, Kumar BVNP, Mandal AB, Bhattacharya SC, Moulik SP. Amphiphile behavior in mixed solvent media I: self-aggregation and ion association of sodium dodecylsulfate in 1,4-dioxane-water and methanol-water media. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:13830-13843. [PMID: 22950843 DOI: 10.1021/la303281d] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Mixed aquo-organic solvents are used in chemical, industrial, and pharmaceutical processes along with amphiphilic materials. Their fundamental studies with reference to bulk and interfacial phenomena are thus considered to be important, but such detailed studies are limited. In this work, the interfacial adsorption of sodium dodecylsulfate (SDS, C12H25SO4(-)Na(+)) in dioxane-water (Dn-W) and methanol-water (Ml-W) media in extensive mixing ratios along with its bulk behavior have been investigated. The solvent-composition-dependent properties have been identified, and their quantifications have been attempted. The SDS micellization has been assessed in terms of different solvent parameters, and the possible formation of an ion pair and triple ion of the colloidal electrolyte, C12H25SO4(-)Na(+) in the Dn-W medium has been correlated and quantified. In the Ml-W medium at a high volume percent of Ml, the SDS amphiphile formed special associated species instead of ion association. The formation of self-assembly and the energetics of SDS in the mixed solvent media have been determined and assessed using conductometry, calorimetry, tensiometry, viscometry, NMR, and DLS methods. The detailed study undertaken herein with respect to the behavior of SDS in the mixed aquo-organic solvent media (Dn-W and Ml-W) is a new kind of endeavor.
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Affiliation(s)
- A Pan
- Centre for Surface Science, Department of Chemistry, Jadavpur University, Kolkata, India
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Mukhim T, Ismail K. Aggregation, Counter Ion Binding and Adsorption Behaviors of Cetylpyridinium Chloride in Water/Glycerol Media at 25 °C. J SURFACTANTS DETERG 2011. [DOI: 10.1007/s11743-011-1281-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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15
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Physicochemical Studies on the Interfacial and Micellization Behavior of CTAB in Aqueous Polyethylene Glycol Media. J SURFACTANTS DETERG 2011. [DOI: 10.1007/s11743-011-1261-8] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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16
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Barbosa AM, Santos IJB, Ferreira GMD, Hespanhol da Silva MDC, Teixeira ÁVNDC, da Silva LHM. Microcalorimetric and SAXS Determination of PEO−SDS Interactions: The Effect of Cosolutes Formed by Ions. J Phys Chem B 2010; 114:11967-74. [DOI: 10.1021/jp1032178] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Aparecida Mageste Barbosa
- Grupo de Química Verde Coloidal e Macromolecular, Departamento de Química and Departamento de Física, Centro de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa, Avenida P. H. Rolfs, Viçosa, MG, 36570-000, Brazil
| | - Igor José Boggione Santos
- Grupo de Química Verde Coloidal e Macromolecular, Departamento de Química and Departamento de Física, Centro de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa, Avenida P. H. Rolfs, Viçosa, MG, 36570-000, Brazil
| | - Guilherme Max Dias Ferreira
- Grupo de Química Verde Coloidal e Macromolecular, Departamento de Química and Departamento de Física, Centro de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa, Avenida P. H. Rolfs, Viçosa, MG, 36570-000, Brazil
| | - Maria do Carmo Hespanhol da Silva
- Grupo de Química Verde Coloidal e Macromolecular, Departamento de Química and Departamento de Física, Centro de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa, Avenida P. H. Rolfs, Viçosa, MG, 36570-000, Brazil
| | - Álvaro Vianna Novaes de Carvalho Teixeira
- Grupo de Química Verde Coloidal e Macromolecular, Departamento de Química and Departamento de Física, Centro de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa, Avenida P. H. Rolfs, Viçosa, MG, 36570-000, Brazil
| | - Luis Henrique Mendes da Silva
- Grupo de Química Verde Coloidal e Macromolecular, Departamento de Química and Departamento de Física, Centro de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa, Avenida P. H. Rolfs, Viçosa, MG, 36570-000, Brazil
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Peng B, Hao Y, Kang H, Han X, Peng C, Liu H. Aggregation behavior of N-carboxyethylchitosan in aqueous solution: effects of pH, polymer concentration, and presence of a gemini surfactant. Carbohydr Res 2010; 345:101-7. [DOI: 10.1016/j.carres.2009.10.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Revised: 10/14/2009] [Accepted: 10/20/2009] [Indexed: 11/16/2022]
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18
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Hussain H, Tan BH, Gudipati CS, He CB, Liu Y, Davis TP. Micelle formation of amphiphilic polystyrene-b-poly(N-vinylpyrrolidone) diblock copolymer in methanol and water-methanol binary mixtures. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:5557-5564. [PMID: 19371048 DOI: 10.1021/la8042389] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The micelle formation by the amphiphilic polystyrene-block-poly(N-vinylpyrrolidone) (PS48-b-PNVP99) copolymer is investigated in methanol and water-methanol binary mixtures of various compositions using 1H NMR, fluorescence spectroscopy, static/dynamic light scattering (SLS/DLS), and transmission electron microscopy (TEM). Critical micelle concentrations (cmc) are determined by employing fluorescence spectroscopy and DLS measurements. The cmc of the PS48-b-PNVP99 block copolymer increases with increasing methanol content in the water-methanol binary mixtures, suggesting that methanol is a better solvent for the PS48-b-PNVP99 block copolymer than water-methanol mixtures or pure water. The amphiphilic PS48-b-PNVP99 diblock copolymer forms spherical micelles of Rh approximately 16 nm in pure methanol solution as revealed by DLS measurements. In contrast, significantly larger micelles having higher aggregation numbers are formed in water-methanol binary mixtures. Temperature dependent data reveal an increase in aggregation number and radius of gyration (Rg) concomitantly with temperature (10-40 degrees C). In contrast, the overall size (Rh) of the micelles remains almost constant over the same temperature range. An explanation is tendered that PNVP coronas dehydrate/desolvate at higher temperatures counteracting the increase in micelle size (Rh) caused by increased aggregation numbers (Nagg).
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Affiliation(s)
- H Hussain
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research, 3 Research Link, Singapore 117602
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Ruiz CC, Díaz‐López L, Aguiar J. Micellization of Sodium Dodecyl Sulfate in Glycerol Aqueous Mixtures. J DISPER SCI TECHNOL 2008. [DOI: 10.1080/01932690701707571] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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20
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Okhrimenko O, Jelesarov I. A survey of the year 2006 literature on applications of isothermal titration calorimetry. J Mol Recognit 2008; 21:1-19. [DOI: 10.1002/jmr.859] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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