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Singh K, Kumar A. Physicochemical aspects for the binding mechanism of sodium carboxymethyl cellulose onto mesoporous tea waste carbon from its aqueous solutions. J DISPER SCI TECHNOL 2022. [DOI: 10.1080/01932691.2020.1842762] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Kaman Singh
- Advanced Centre of Surface Chemistry, Department of Chemistry, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, Uttar Pradesh, India
| | - Ashok Kumar
- Advanced Centre of Surface Chemistry, Department of Chemistry, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, Uttar Pradesh, India
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Singh K, Kumar A, Pandey SK, Awasthi S, Gupta SP, Mishra P. Interpretation of Adsorption Behavior of Carboxymethyl Cellulose onto Functionalized Accurel Polymeric Surface. Ind Eng Chem Res 2020. [DOI: 10.1021/acs.iecr.0c03894] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kaman Singh
- Advanced Centre of Surface Chemistry, Department of Chemistry, Babasaheb Bhimrao Ambedkar University (A Central University) Lucknow, Lucknow 226025, Uttar Pradesh, India
- Department of Chemistry, Faculty of Science, University of Lucknow, Lucknow 226007, Uttar Pradesh, India
| | - Ashok Kumar
- Advanced Centre of Surface Chemistry, Department of Chemistry, Babasaheb Bhimrao Ambedkar University (A Central University) Lucknow, Lucknow 226025, Uttar Pradesh, India
| | - Sarvesh Kumar Pandey
- Department of Inorganic and Physical Chemistry, Indian Institute of Science Bangalore, Bangalore 560012, Karnataka, India
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India
| | - Shikha Awasthi
- Department of Materials Engineering, Indian Institute of Science Bangalore, Bangalore 560012, Karnataka, India
| | - Satya Prakash Gupta
- Advanced Centre of Surface Chemistry, Department of Chemistry, Babasaheb Bhimrao Ambedkar University (A Central University) Lucknow, Lucknow 226025, Uttar Pradesh, India
| | - Prashant Mishra
- Advanced Centre of Surface Chemistry, Department of Chemistry, Babasaheb Bhimrao Ambedkar University (A Central University) Lucknow, Lucknow 226025, Uttar Pradesh, India
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Singh K, Kumar A, Mishra P, Gupta SP. Binding aspects of carboxymethyl cellulose onto polymeric surface from its aqueous solutions. J DISPER SCI TECHNOL 2020. [DOI: 10.1080/01932691.2020.1786396] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Kaman Singh
- Advanced Center of Surface Chemistry, Department of Chemistry, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, U.P., India
| | - Ashok Kumar
- Advanced Center of Surface Chemistry, Department of Chemistry, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, U.P., India
| | - Prashant Mishra
- Advanced Center of Surface Chemistry, Department of Chemistry, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, U.P., India
| | - Satya Prakash Gupta
- Advanced Center of Surface Chemistry, Department of Chemistry, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, U.P., India
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Recent advances in studies of bubble-solid interactions and wetting film stability. Curr Opin Colloid Interface Sci 2019. [DOI: 10.1016/j.cocis.2019.09.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Adsorption mechanism of carboxymethyl cellulose onto mesoporous mustard carbon: Experimental and theoretical aspects. Colloids Surf A Physicochem Eng Asp 2019. [DOI: 10.1016/j.colsurfa.2019.123786] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Yuan D, Cadien K, Liu Q, Zeng H. Adsorption characteristics and mechanisms of O-Carboxymethyl chitosan on chalcopyrite and molybdenite. J Colloid Interface Sci 2019; 552:659-670. [DOI: 10.1016/j.jcis.2019.05.023] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 04/23/2019] [Accepted: 05/05/2019] [Indexed: 02/02/2023]
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An Alternative Depressant of Chalcopyrite in Cu–Mo Differential Flotation and Its Interaction Mechanism. MINERALS 2018. [DOI: 10.3390/min9010001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Carboxymethylcellulose (CMC) is a nontoxic and biodegradable polysaccharide, which can potentially replace the frequently used hazardous depressants in Cu–Mo separation. However, a lack of understanding of the interaction mechanism between the CMC and the minerals has hindered its application. In the present study, it is found that 50 mg·L−1 CMC can inhibit chalcopyrite entirely in the pH range 4–6, while having little effect on molybdenite. The results also showed that the inhibition effect of the depressant for chalcopyrite enhanced with the increase of the degree of substitution (DS) and molecular weight (Mw) of CMC. The low DS and high Mw of CMC were detrimental to the Cu–Mo separation flotation. Furthermore, CMC adsorption was found to be favored by a positive zeta potential but hindered by the protonation of the carboxyl groups. An electrochemical study showed that CMC inhibited 92.9% of the electrochemical reaction sites of chalcopyrite and greatly reduced the production of hydrophobic substances. The XPS and FTIR measurements displayed that the chemisorption was mainly caused by Fe3+ on the chalcopyrite surface and the carboxyl groups in the CMC molecular structure.
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Ren L, Qiu H, Zhang Y, Nguyen AV, Zhang M, Wei P, Long Q. Effects of alkyl ether amine and calcium ions on fine quartz flotation and its guidance for upgrading vanadium from stone coal. POWDER TECHNOL 2018. [DOI: 10.1016/j.powtec.2018.07.026] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Fagundes KRS, Luz RCDS, Fagundes FP, Balaban RDC. Effect of carboxymethylcellulose on colloidal properties of calcite suspensions in drilling fluids. POLIMEROS 2018. [DOI: 10.1590/0104-1428.11817] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Zhu C, Soldatov A, Mathew AP. Advanced microscopy and spectroscopy reveal the adsorption and clustering of Cu(ii) onto TEMPO-oxidized cellulose nanofibers. NANOSCALE 2017; 9:7419-7428. [PMID: 28530277 DOI: 10.1039/c7nr01566f] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
TEMPO (2,2,6,6-tetramethylpiperidine-1-oxylradical)-mediated oxidation nanofibers (TOCNF), as a biocompatible and bioactive material, have opened up a new application of nanocellulose for the removal of water contaminants. This development demands extremely sensitive and accurate methods to understand the surface interactions between water pollutants and TOCNF. In this report, we investigated the adsorption of metal ions on TOCNF surfaces using experimental techniques atthe nano and molecular scales with Cu(ii) as the target pollutant in both aqueous and dry forms. Imaging with in situ atomic force microscopy (AFM), together with a study of the physiochemical properties of TOCNF caused by adsorption with Cu(ii) in liquid, were conducted using the PeakForce Quantitative NanoMechanics (PF-QNM) mode at the nano scale. The average adhesion force between the tip and the target single TOCNF almost tripled after adsorption with Cu(ii) from 50 pN to 140 pN. The stiffness of the TOCNF was also enhanced because the Cu(ii) bound to the carboxylate groups and hardened the fiber. AFM topography, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) mapping and X-ray photoelectron spectroscopy (XPS) indicated that the TOCNF were covered by copper nanolayers and/or nanoparticles after adsorption. The changes in the molecular structure caused by the adsorption were demonstrated by Raman and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). This methodology will be of great assistance to gain qualitative and quantitative information on the adsorption process and interaction between charged entities in aqueous medium.
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Affiliation(s)
- Chuantao Zhu
- Department of Materials and Environmental Chemistry, Stockholm University, 10691, Stockholm, Sweden.
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Xie L, Wang J, Yuan D, Shi C, Cui X, Zhang H, Liu Q, Liu Q, Zeng H. Interaction Mechanisms between Air Bubble and Molybdenite Surface: Impact of Solution Salinity and Polymer Adsorption. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:2353-2361. [PMID: 28191980 DOI: 10.1021/acs.langmuir.6b04611] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The surface characteristics of molybdenite (MoS2) such as wettability and surface interactions have attracted much research interest in a wide range of engineering applications, such as froth flotation. In this work, a bubble probe atomic force microscope (AFM) technique was employed to directly measure the interaction forces between an air bubble and molybdenite mineral surface before/after polymer (i.e., guar gum) adsorption treatment. The AFM imaging showed that the polymer coverage on the surface of molybdenite could achieve ∼5.6, ∼44.5, and ∼100% after conditioning in 1, 5, and 10 ppm polymer solution, respectively, which coincided with the polymer coverage results based on contact angle measurements. The electrolyte concentration and surface treatment by polymer adsorption were found to significantly affect bubble-mineral interaction and attachment. The experimental force results on bubble-molybdenite (without polymer treatment) agreed well with the calculations using a theoretical model based on the Reynolds lubrication theory and augmented Young-Laplace equation including the effect of disjoining pressure. The overall surface repulsion was enhanced when the NaCl concentration decreased from 100 to 1 mM, which inhibited the bubble-molybdenite attachment. After conditioning the molybdenite surface in 1 ppm polymer solution, it was more difficult for air bubbles to attach to the molybdenite surface due to the weakened hydrophobic interaction with a shorter decay length. Increasing the polymer concentration to 5 ppm effectively inhibited bubble attachment on mineral surface, which was mainly due to the much reduced hydrophobic interaction as well as the additional steric repulsion between the extended polymer chains and bubble surface. The results provide quantitative information on the interaction mechanism between air bubbles and molybdenite mineral surfaces on the nanoscale, with useful implications for the development of effective polymer depressants and fundamental understanding of bubble-solid interactions in mineral flotation. The methodologies used in this work can be readily extended to studying similar interfacial interactions in many other engineering applications such as froth flotation deinking and bitumen extraction in oil sands industry.
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Affiliation(s)
- Lei Xie
- Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta T6G 1H9, Canada
| | - Jingyi Wang
- Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta T6G 1H9, Canada
| | - Duowei Yuan
- Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta T6G 1H9, Canada
| | - Chen Shi
- Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta T6G 1H9, Canada
| | - Xin Cui
- Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta T6G 1H9, Canada
| | - Hao Zhang
- Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta T6G 1H9, Canada
| | - Qi Liu
- Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta T6G 1H9, Canada
| | - Qingxia Liu
- Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta T6G 1H9, Canada
| | - Hongbo Zeng
- Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta T6G 1H9, Canada
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Fan XH, Yang GM, Chen XL, He XN, Huang XX, Gao L. Effect of carboxymethyl cellulose on the drying dynamics and thermal cracking performance of iron ore green pellets. POWDER TECHNOL 2014. [DOI: 10.1016/j.powtec.2014.07.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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14
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Kor M, Korczyk PM, Addai-Mensah J, Krasowska M, Beattie DA. Carboxymethylcellulose adsorption on molybdenite: the effect of electrolyte composition on adsorption, bubble-surface collisions, and flotation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:11975-84. [PMID: 25232682 DOI: 10.1021/la503248e] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The adsorption of carboxymethylcellulose polymers on molybdenite was studied using spectroscopic ellipsometry and atomic force microscopy imaging with two polymers of differing degrees of carboxyl group substitution and at three different electrolyte conditions: 1 × 10(-2) M KCl, 2.76 × 10(-2) M KCl, and simulated flotation process water of multicomponent electrolyte content, with an ionic strength close to 2.76 × 10(-2) M. A higher degree of carboxyl substitution in the adsorbing polymer resulted in adsorbed layers that were thinner and with more patchy coverage; increasing the ionic strength of the electrolyte resulted in increased polymer layer thickness and coverage. The use of simulated process water resulted in the largest layer thickness and coverage for both polymers. The effect of the adsorbed polymer layer on bubble-particle attachment was studied with single bubble-surface collision experiments recorded with high-speed video capture and image processing and also with single mineral molybdenite flotation tests. The carboxymethylcellulose polymer with a lower degree of substitution resulted in almost complete prevention of wetting film rupture at the molybdenite surface under all electrolyte conditions. The polymer with a higher degree of substitution prevented rupture only when adsorbed from simulated process water. Molecular kinetic theory was used to quantify the effect of the polymer on the dewetting dynamics for collisions that resulted in wetting film rupture. Flotation experiments confirmed that adsorbed polymer layer properties, through their effect on the dynamics of bubble-particle attachment, are critical to predicting the effectiveness of polymers used to prevent mineral recovery in flotation.
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Affiliation(s)
- Mohammad Kor
- Ian Wark Research Institute, University of South Australia , Mawson Lakes, SA 5095, Australia
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Pensini E, Sleep BE, Yip CM, O’Carroll D. Forces of interactions between iron and aluminum silicates: Effect of water chemistry and polymer coatings. J Colloid Interface Sci 2013; 411:8-15. [DOI: 10.1016/j.jcis.2013.08.047] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 08/24/2013] [Indexed: 11/30/2022]
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Dilute solution properties of carboxymethyl celluloses of various molecular weights and degrees of substitution. Carbohydr Polym 2013; 99:423-31. [PMID: 24274526 DOI: 10.1016/j.carbpol.2013.08.030] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2013] [Revised: 08/12/2013] [Accepted: 08/15/2013] [Indexed: 11/21/2022]
Abstract
The intrinsic viscosities of six carboxymethyl celluloses (CMC) of different degrees of substitution, molecular weights, and molecular weight distributions (MWDs) were measured as a function of pH, ionic strength, and temperature. The molecular weights and MWDs were determined by analytical ultracentrifugation. It was demonstrated that the raw viscosity data could be represented by the Fedors equation allowing for accurate determination of the intrinsic viscosity. Ionic strength, rather than pH or temperature had the strongest effect on the conformation of CMC. An estimate of the Mark-Houwink-Kuhn-Sakurada exponent (α=0.83) and calculations of chain flexibility and expansion factors indicated that CMC has semi-flexible, randomly coiling chains in solution with persistence lengths on the order of 8.8-24.5 nm in distilled water and 11.3-14.8 nm in 0.01 mol/L sodium chloride. It was also found that the lowest molecular weight CMC was most flexible among the tested samples.
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Pensini E, Yip CM, O’Carroll D, Sleep BE. Carboxymethyl cellulose binding to mineral substrates: Characterization by atomic force microscopy–based Force spectroscopy and quartz-crystal microbalance with dissipation monitoring. J Colloid Interface Sci 2013; 402:58-67. [DOI: 10.1016/j.jcis.2013.03.053] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 03/29/2013] [Accepted: 03/31/2013] [Indexed: 11/26/2022]
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Mierczynska-Vasilev A, Beattie DA. The effect of impurities and cleavage characteristics on talc hydrophobicity and polymer adsorption. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.minpro.2012.11.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Kargl R, Mohan T, Bračič M, Kulterer M, Doliška A, Stana-Kleinschek K, Ribitsch V. Adsorption of carboxymethyl cellulose on polymer surfaces: evidence of a specific interaction with cellulose. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:11440-11447. [PMID: 22759080 DOI: 10.1021/la302110a] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The adsorption of carboxymethyl cellulose (CMC), one of the most important cellulose derivatives, is crucial for many scientific investigations and industrial applications. Especially for surface modifications and functionalization of materials, the polymer is of interest. The adsorption properties of CMC are dependent not only on the solutions state, which can be influenced by the pH, temperature, and electrolyte concentration, but also on the chemical composition of the adsorbents. We therefore performed basic investigation studies on the interaction of CMC with a variety of polymer films. Thin films of cellulose, cellulose acetate, deacetylated cellulose acetate, polyethylene terephthalate, and cyclo olefin polymer were therefore prepared on sensors of a QCM-D (quartz crystal microbalance) and on silicon substrates. The films were characterized with respect to the thickness, wettability, and chemical composition. Subsequently, the interaction and deposition of CMC in a range of pH values without additional electrolyte were measured with the QCM-D method. A comparison of the QCM-D results showed that CMC is favorably deposited on pure cellulose films and deacetylated cellulose acetate at low pH values. Other hydrophilic surfaces such as silicon dioxide or polyvinyl alcohol coated surfaces did not adsorb CMC to a significant extent. Atomic force microcopy confirmed that the morphology of the adsorbed CMC layers differed depending on the substrate. On hydrophobic polymer films, CMC was deposited in the form of larger particles in lower amounts whereas hydrophilic cellulose substrates were to a high extent uniformly covered by adsorbed CMC. The chemical similarity of the CMC backbone seems to favor the irreversible adsorption of CMC when the molecule is almost uncharged at low pH values. A selectivity of the cellulose CMC interaction can therefore be assumed. All CMC treated polymer films exhibited an increased hydrophilicity, which confirmed their modification with the functional molecule.
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Affiliation(s)
- Rupert Kargl
- Institute of Chemistry, Karl-Franzens-University Graz, Graz, Austria.
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Adsorption of modified dextrins on molybdenite: AFM imaging, contact angle, and flotation studies. J Colloid Interface Sci 2012; 368:608-15. [DOI: 10.1016/j.jcis.2011.10.075] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Revised: 10/30/2011] [Accepted: 10/31/2011] [Indexed: 11/19/2022]
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Beaussart A, Mierczynska-Vasilev AM, Harmer SL, Beattie DA. The role of mineral surface chemistry in modified dextrin adsorption. J Colloid Interface Sci 2011; 357:510-20. [DOI: 10.1016/j.jcis.2011.02.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Accepted: 02/05/2011] [Indexed: 11/26/2022]
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Sedeva IG, Fornasiero D, Ralston J, Beattie DA. Reduction of surface hydrophobicity using a stimulus-responsive polysaccharide. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:15865-15874. [PMID: 20853820 DOI: 10.1021/la101695w] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The adsorption of carboxymethyl cellulose (CMC) onto a hydrophobic self-assembled monolayer has been characterized using the quartz crystal microbalance (with dissipation monitoring, QCM-D). Adsorption was studied as a function of initial solution conditions. CMC adsorbs to a greater extent at high ionic strength (10(-1) M KCl as opposed to 10(-2) M KCl) or low pH (3 as opposed to 9). The solution conditions that yielded the lowest initial adsorbed amount (10(-2) M KCl, pH 9) were used as a reference to investigate the response of the adsorbed layer to a switch in solution conditions after adsorption (i.e., to higher ionic strength (10(-1) M KCl) or lower pH (pH 3)). The adsorbed layer released significant amounts of hydration water after each solution switch, as determined by the QCM-D measurements. This expulsion of hydration water was fully reversible. For the two solution switches, reducing the solution pH resulted in a more pronounced change in the amount of hydration water within the adsorbed CMC, accompanied by a distinct conformational change, as determined from a QCM D-f plot. In addition to studying adsorption using QCM-D, the effect of adsorbed CMC on surface hydrophobicity has been investigated using captive bubble contact angle measurements. The effect of the polymer on the contact angle of the surface was seen to be greatest when adsorbed at low pH or at higher ionic strength. CMC was also seen to have a significantly enhanced ability to reduce the surface hydrophobicity after both the ionic strength and pH switches, lowering the advancing water contact angle by 6 and 23° and the receding water contact angle by 10 and 40° for the ionic strength and pH switches, respectively. As with the change in hydration water content, the change in the contact angle of the polymer-coated surface following the solution switches was reversible.
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Affiliation(s)
- Iliana G Sedeva
- Ian Wark Research Institute, University of South Australia, Mawson Lakes, Adelaide, SA 5095, Australia
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