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Yamamoto A, Inui T, Suzuki D, Urayama K. Stress-independent delay time in yielding of dilute colloidal gels. SOFT MATTER 2023; 19:9082-9091. [PMID: 37987474 DOI: 10.1039/d3sm01238g] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
We investigate the yielding under shear for dilute poly(N-isopropyl acrylamide-co-fumaric acid) (PNIPAM-FAc) colloidal gels obtained above the volume phase transition temperature. In this temperature range, the microgel suspensions form colloidal gels due to hydrophobic interparticle interactions under appropriate pH and ionic strength conditions. Step-strain tests revealed that yielding occurs when the applied strain exceeds a specific threshold, requiring a finite, stress-independent delay time (tD). This is distinct from previous findings on delayed yielding in other colloidal gels, where tD decreases with increasing stress. In the start-up shear tests, yield strain (γy) at a higher strain rate () increases with escalating , while γy at lower remains constant. This characteristic γy- relationship is successfully explained by a simple model using the stress-independent tD value without an adjustable fitting parameter. The distinctive yielding behavior, underscored by a stress-independent tD, is expected to originate from strain-induced macroscopic phase separation into a dense colloidal gel and water, observable separately from rheological measurements.
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Affiliation(s)
- Atsushi Yamamoto
- Department of Macromolecular Science and Engineering, Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585, Japan
| | - Takumi Inui
- Graduate School of Textile Science & Technology, Shinshu University, Ueda 386-8567, Japan.
| | - Daisuke Suzuki
- Graduate School of Textile Science & Technology, Shinshu University, Ueda 386-8567, Japan.
- Research Initiative for Supra-Materials, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Ueda 386-8567, Japan
| | - Kenji Urayama
- Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan.
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2
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Akgonullu DZ, Murray BS, Connell SD, Fang Y, Linter B, Sarkar A. Synthetic and biopolymeric microgels: Review of similarities and difference in behaviour in bulk phases and at interfaces. Adv Colloid Interface Sci 2023; 320:102983. [PMID: 37690329 DOI: 10.1016/j.cis.2023.102983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 08/12/2023] [Accepted: 08/14/2023] [Indexed: 09/12/2023]
Abstract
This review discusses the current knowledge of interfacial and bulk interactions of biopolymeric microgels in relation to the well-established properties of synthetic microgels for applications as viscosity modifiers and Pickering stabilisers. We present a timeline showing the key milestones in designing microgels and their bulk/ interfacial performance. Poly(N-isopropylacrylamide) (pNIPAM) microgels have remained as the protagonist in the synthetic microgel domain whilst proteins or polysaccharides have been primarily used to fabricate biopolymeric microgels. Bulk properties of microgel dispersions are dominated by the volume fraction (ϕ) of the microgel particles, but ϕ is difficult to pinpoint, as addressed by many theoretical models. By evaluating recent experimental studies over the last five years, we find an increasing focus on the analysis of microgel elasticity as a key parameter in modulating their packing at the interfaces, within the provinces of both synthetic and biopolymeric systems. Production methods and physiochemical factors shown to influence microgel swelling in the aqueous phase can have a significant impact on their bulk as well as interfacial performance. Compared to synthetic microgels, biopolymer microgels show a greater tendency for polydispersity and aggregation and do not appear to have a core-corona structure. Comprehensive studies of biopolymeric microgels are still lacking, for example, to accurately determine their inter- and intra- particle interactions, whilst a wider variety of techniques need to be applied in order to allow comparisons to real systems of practical usage.
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Affiliation(s)
- Daisy Z Akgonullu
- Food Colloids and Bioprocessing Group, School of Food Science and Nutrition, University of Leeds, UK
| | - Brent S Murray
- Food Colloids and Bioprocessing Group, School of Food Science and Nutrition, University of Leeds, UK
| | - Simon D Connell
- Molecular and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, UK
| | - Yuan Fang
- PepsiCo, Valhalla, New York, NY, USA
| | | | - Anwesha Sarkar
- Food Colloids and Bioprocessing Group, School of Food Science and Nutrition, University of Leeds, UK.
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3
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Teoh JY, Jeon S, Yim B, Yang HM, Hwang Y, Kim J, Lee SK, Park E, Kong TY, Kim SY, Park Y, Kim YG, Kim J, Yoo D. Tuning Surface Plasmon Resonance Responses through Size and Crosslinking Control of Multivalent Protein Binding-Capable Nanoscale Hydrogels. ACS Biomater Sci Eng 2022; 8:2878-2889. [PMID: 35658391 DOI: 10.1021/acsbiomaterials.2c00250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Surface plasmon resonance (SPR) phenomena have been widely studied to detect biomolecules because of their high sensitivity and ability to determine biomolecular interactions with kinetic information. However, highly selective detection in specific concentration ranges relevant to target biomolecules is still a challenging task. Recently, we developed bioresponsive nanoscale hydrogels to selectively intensify SPR signals through multivalent protein binding (MPB) events with target biomolecules, including IL-2, where we were able to demonstrate exceptional selectivity for target biomolecules with minimal responses to nonspecific and monovalent binding events. In this work, we systematically explored the relationship between the physical properties of MPB-capable nanoscale hydrogels and their SPR response induced in the presence of the programmed cell death protein 1 antibody (PD-1Ab) as a model target biomolecule. First, we developed a synthetic protocol by controlling various reaction parameters to construct a library of nanoscale poly(N-isopropylacrylamide-co-acrylic acid) hydrogels (NHs) with different sizes (from 400 nm to 1 μm) and degrees of crosslinking (from 2 to 8%). Then, by incorporating MPB-capable PD-1 receptors onto the surface of NHs to form PD-1-responsive nanoscale hydrogels (PNHs), the hydrogel size and crosslinking dependency of their SPR responses were investigated. Our results reveal the appropriate hydrogel size regime and degree of crosslinking for effective PD-1Ab detection at specific concentrations range between a few nM and 1 μM. Overall, our study demonstrates that by tuning the physical properties of the nanoscale hydrogel matrix, the sensitivity and detection range of MPB-based SPR sensors can be modulated to potentially benefit clinical applications such as monitoring diverse therapeutic biomolecules.
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Affiliation(s)
- Jie Ying Teoh
- Department of Chemical and Biological Engineering, and Institute of Chemical Process, Seoul National University, Seoul 08826, Republic of Korea
| | - Suhwan Jeon
- Department of Chemical and Biological Engineering, and Institute of Chemical Process, Seoul National University, Seoul 08826, Republic of Korea
| | - Bora Yim
- R&D Center, Scholar Foxtrot Co. Ltd., Seoul 02841, Republic of Korea.,Department of Biomedical Sciences, College of Medicine, Korea University, Seoul 02841, Republic of Korea
| | - Hae Min Yang
- Department of Chemical and Biological Engineering, and Institute of Chemical Process, Seoul National University, Seoul 08826, Republic of Korea
| | - Yunseo Hwang
- Department of Chemical and Biological Engineering, and Institute of Chemical Process, Seoul National University, Seoul 08826, Republic of Korea
| | - Juhui Kim
- Department of Chemical and Biological Engineering, and Institute of Chemical Process, Seoul National University, Seoul 08826, Republic of Korea
| | - Su-Kyoung Lee
- R&D Center, Scholar Foxtrot Co. Ltd., Seoul 02841, Republic of Korea.,Department of Biomedical Sciences, College of Medicine, Korea University, Seoul 02841, Republic of Korea
| | - Eunyoung Park
- Department of Chemical and Biological Engineering, and Institute of Chemical Process, Seoul National University, Seoul 08826, Republic of Korea
| | - Tae Yeon Kong
- Department of Chemical and Biological Engineering, and Institute of Chemical Process, Seoul National University, Seoul 08826, Republic of Korea
| | - So Youn Kim
- Department of Chemical and Biological Engineering, and Institute of Chemical Process, Seoul National University, Seoul 08826, Republic of Korea
| | - Yongdoo Park
- Department of Biomedical Sciences, College of Medicine, Korea University, Seoul 02841, Republic of Korea
| | - Young Gyu Kim
- Department of Chemical and Biological Engineering, and Institute of Chemical Process, Seoul National University, Seoul 08826, Republic of Korea
| | - Jongseong Kim
- R&D Center, Scholar Foxtrot Co. Ltd., Seoul 02841, Republic of Korea.,Department of Biomedical Sciences, College of Medicine, Korea University, Seoul 02841, Republic of Korea
| | - Dongwon Yoo
- Department of Chemical and Biological Engineering, and Institute of Chemical Process, Seoul National University, Seoul 08826, Republic of Korea.,Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
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4
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Echeverría C, Mijangos C. Rheology Applied to Microgels: Brief (Revision of the) State of the Art. Polymers (Basel) 2022; 14:1279. [PMID: 35406152 PMCID: PMC9003433 DOI: 10.3390/polym14071279] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 03/18/2022] [Accepted: 03/18/2022] [Indexed: 12/10/2022] Open
Abstract
The ability of polymer microgels to rapidly respond to external stimuli is of great interest in sensors, lubricants, and biomedical applications, among others. In most of their uses, microgels are subjected to shear, deformation, and compression forces or a combination of them, leading to variations in their rheological properties. This review article mainly refers to the rheology of microgels, from the hard sphere versus soft particles' model. It clearly describes the scaling theories and fractal structure formation, in particular, the Shih et al. and Wu and Morbidelli models as a tool to determine the interactions among microgel particles and, thus, the viscoelastic properties. Additionally, the most recent advances on the characterization of microgels' single-particle interactions are also described. The review starts with the definition of microgels, and a brief introduction addresses the preparation and applications of microgels and hybrid microgels.
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Affiliation(s)
- Coro Echeverría
- Instituto de Ciencia y Tecnología de Polímeros (ICTP-CSIC), C/Juan de la Cierva 3, 28006 Madrid, Spain;
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5
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Frenzel L, Dartsch M, Balaguer GM, Westermeier F, Grübel G, Lehmkühler F. Glass-liquid and glass-gel transitions of soft-shell particles. Phys Rev E 2021; 104:L012602. [PMID: 34412357 DOI: 10.1103/physreve.104.l012602] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 06/23/2021] [Indexed: 12/12/2022]
Abstract
We study the structure and dynamics of colloidal particles with a spherical hard core and a thermo-responsive soft shell over the whole phase diagram by means of small-angle x-ray scattering and x-ray photon correlation spectroscopy. By changing the effective volume fraction by temperature and particle concentration, liquid, repulsive glass. and attractive gel phases are observed. The dynamics slow down with increasing volume fraction in the liquid phase and reflect a Vogel-Fulcher-Tamann behavior known for fragile glass formers. We find a liquid-glass transition above 50 vol.% that is independent of the particles' concentration and temperature. In an overpacked state at effective volume fractions above 1, the dispersion does not show a liquid phase but undergoes a gel-glass transition at an effective volume fraction of 34 vol.%. At the same concentration, extrema of subdiffusive dynamics are found in the liquid phase at lower weight fractions. We interpret this as dynamic precursors of the glass-gel transition.
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Affiliation(s)
- Lara Frenzel
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany.,The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Michael Dartsch
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany.,The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | | | - Fabian Westermeier
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Gerhard Grübel
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany.,The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Felix Lehmkühler
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany.,The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
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6
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Najafi M, Habibi M, Fokkink R, Hennink WE, Vermonden T. LCST polymers with UCST behavior. SOFT MATTER 2021; 17:2132-2141. [PMID: 33439188 DOI: 10.1039/d0sm01505a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In this study, temperature dependent behavior of dense dispersions of core crosslinked flower-like micelles is investigated. Micelles were prepared by mixing aqueous solutions of two ABA block copolymers with PEG B-blocks and thermosensitive A-blocks containing PNIPAM and crosslinkable moieties. At a temperature above the lower critical solution temperature (LCST), self-assembly of the polymers resulted in the formation of flower-like micelles with a hydrophilic PEG shell and a hydrophobic core. The micellar core was stabilized by native chemical ligation (NCL). Above the LCST, micelles displayed a radius of ∼35 nm, while a radius of ∼48 nm was found below the LCST due to hydration of the PNIPAM core. Concentrated dispersions of these micelles (≥7.5 wt%) showed glassy state behavior below a critical temperature (Tc: 28 °C) which is close to the LCST of the polymers. Below this Tc, the increase in the micelle volume resulted in compression of micelles together above a certain concentration and formation of a glass. We quantified and compared micelle packing at different concentrations and temperatures. The storage moduli (G') of the dispersions showed a universal dependence on the effective volume fraction, which increased substantially above a certain effective volume fraction of φ = 1.2. Furthermore, a disordered lattice model describing this behavior fitted the experimental data and revealed a critical volume fraction of φc = 1.31 close to the experimental value of φ = 1.2. The findings reported provide insights for the molecular design of novel thermosensitive PNIPAM nanoparticles with tunable structural and mechanical properties.
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Affiliation(s)
- Marzieh Najafi
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences (UIPS), Science for Life, Faculty of Science, Utrecht University, P. O. Box 80082, 3508 TB Utrecht, The Netherlands.
| | - Mehdi Habibi
- Physics and Physical Chemistry of Foods, Wageningen University & Research, 6708 WG Wageningen, Wageningen, The Netherlands
| | - Remco Fokkink
- Physical Chemistry and Soft Matter, Wageningen University & Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Wim E Hennink
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences (UIPS), Science for Life, Faculty of Science, Utrecht University, P. O. Box 80082, 3508 TB Utrecht, The Netherlands.
| | - Tina Vermonden
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences (UIPS), Science for Life, Faculty of Science, Utrecht University, P. O. Box 80082, 3508 TB Utrecht, The Netherlands.
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7
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Jiang R, Li J, Qiang Z, Wang L, Wang T, Shi S. Synthesis and In Situ Gelation Behavior of Thermoresponsive Poly(N-isopropylacrylamide)/Chitosan Microgels. J MACROMOL SCI B 2020. [DOI: 10.1080/00222348.2020.1841413] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Rui Jiang
- Department of Materials Chemistry, College of Materials Science and Engineering, Shenyang University of Chemical Technology, Shenyang, China
| | - Jiaxi Li
- Department of Materials Chemistry, College of Materials Science and Engineering, Shenyang University of Chemical Technology, Shenyang, China
| | - Zhelin Qiang
- Department of Materials Chemistry, College of Materials Science and Engineering, Shenyang University of Chemical Technology, Shenyang, China
| | - Ling Wang
- Department of Materials Chemistry, College of Materials Science and Engineering, Shenyang University of Chemical Technology, Shenyang, China
| | - Tao Wang
- Department of Materials Chemistry, College of Materials Science and Engineering, Shenyang University of Chemical Technology, Shenyang, China
| | - Shan Shi
- Department of Materials Chemistry, College of Materials Science and Engineering, Shenyang University of Chemical Technology, Shenyang, China
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8
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Frenzel L, Lokteva I, Koof M, Narayanan S, Grübel G, Lehmkühler F. Influence of TMAO as co-solvent on the gelation of silica-PNIPAm core-shell nanogels at intermediate volume fractions. Chemphyschem 2020; 21:1318-1325. [PMID: 32250508 PMCID: PMC7318175 DOI: 10.1002/cphc.202000114] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 03/20/2020] [Indexed: 12/29/2022]
Abstract
We study the structure and dynamics of poly(N-isopropylacrylamide) (PNIPAm) core-shell nanogels dispersed in aqueous trimethylamine N-oxide (TMAO) solutions by means of small-angle X-ray scattering and X-ray photon correlation spectroscopy (XPCS). Upon increasing the temperature above the lower critical solution temperature of PNIPAm at 33 °C, a colloidal gel is formed as identified by an increase of I(q) at small q as well as a slowing down of sample dynamics by various orders of magnitude. With increasing TMAO concentration the gelation transition shifts linearly to lower temperatures. Above a TMAO concentration of approximately 0.40 mol/L corresponding to a 1 : 1 ratio of TMAO and NIPAm groups, collapsed PNIPAm states are found for all temperatures without any gelation transition. This suggests that reduction of PNIPAm-water hydrogen bonds due to the presence of TMAO results in a stabilisation of the collapsed PNIPAm state and suppresses gelation of the nanogel.
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Affiliation(s)
- Lara Frenzel
- Deutsches Elektronen-Synchrotron DESYNotkestr. 8522607HamburgGermany
- The Hamburg Centre for Ultrafast ImagingLuruper Chaussee 14922761HamburgGermany
| | - Irina Lokteva
- Deutsches Elektronen-Synchrotron DESYNotkestr. 8522607HamburgGermany
- The Hamburg Centre for Ultrafast ImagingLuruper Chaussee 14922761HamburgGermany
| | - Michael Koof
- Deutsches Elektronen-Synchrotron DESYNotkestr. 8522607HamburgGermany
- The Hamburg Centre for Ultrafast ImagingLuruper Chaussee 14922761HamburgGermany
| | - Suresh Narayanan
- Advanced Photon SourceArgonne National LaboratoryArgonneIllinois60439United States
| | - Gerhard Grübel
- Deutsches Elektronen-Synchrotron DESYNotkestr. 8522607HamburgGermany
- The Hamburg Centre for Ultrafast ImagingLuruper Chaussee 14922761HamburgGermany
| | - Felix Lehmkühler
- Deutsches Elektronen-Synchrotron DESYNotkestr. 8522607HamburgGermany
- The Hamburg Centre for Ultrafast ImagingLuruper Chaussee 14922761HamburgGermany
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9
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Minami S, Yamamoto A, Oura S, Watanabe T, Suzuki D, Urayama K. Criteria for colloidal gelation of thermo-sensitive poly(N-isopropylacrylamide) based microgels. J Colloid Interface Sci 2020; 568:165-175. [DOI: 10.1016/j.jcis.2020.02.047] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 02/12/2020] [Accepted: 02/13/2020] [Indexed: 11/24/2022]
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10
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Mackiewicz M, Stojek Z, Karbarz M. Synthesis of cross-linked poly(acrylic acid) nanogels in an aqueous environment using precipitation polymerization: unusually high volume change. ROYAL SOCIETY OPEN SCIENCE 2019; 6:190981. [PMID: 31827839 PMCID: PMC6894567 DOI: 10.1098/rsos.190981] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 10/04/2019] [Indexed: 05/30/2023]
Abstract
For the first time, by using precipitation polymerization in an aqueous solution, a cross-linked poly(acrylic acid)-(pAA) nanogel was synthesized. pAA was synthesized and cross-linked with N,N'-methylenebisacrylamide (BIS) at 70°C in an acidified environment (pH 2) and containing 0.7 M NaCl using potassium persulfate as the initiator. Ionized pAA was soluble in water. The use of sodium chloride at low pH caused a decrease in the solubility of pAA and led to its precipitation and formation of cross-linked pAA nanogel. By using electron microscopies and light scattering techniques, the morphology, pH sensitivity and zeta potential of the obtained p(AA-BIS) nanogel were evaluated. The polymerization in an aqueous environment resulted in a very big swelling/shrinking coefficient (of approx. 4000) in response to pH and exhibited an unusually high negative zeta potential (of approx. -130 mV). These properties make the nanogel a very interesting sorbent and a construction material.
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Affiliation(s)
| | | | - Marcin Karbarz
- Faculty of Chemistry, Biological and Chemical Research Center, University of Warsaw, 101 Żwirki i Wigury Avenue, 02-089 Warsaw, Poland
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11
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Echeverría C, Mijangos C. A Way to Predict Gold Nanoparticles/Polymer Hybrid Microgel Agglomeration Based on Rheological Studies. NANOMATERIALS (BASEL, SWITZERLAND) 2019; 9:E1499. [PMID: 31640156 PMCID: PMC6835908 DOI: 10.3390/nano9101499] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 10/09/2019] [Accepted: 10/11/2019] [Indexed: 12/12/2022]
Abstract
In this work, a detailed rheological study of hybrid poly(acrylamide-co-acrylic acid) P(AAm-co-AAc) aqueous microgel dispersions is performed. Our intention is to understand how the presence of gold nanoparticles, AuNP, embedded within the microgel matrix, affects the viscoelastic properties, the colloidal gel structure formation, and the structure recovery after cessation of the deformation of the aqueous microgel dispersions. Frequency sweep experiments confirmed that hybrid microgel dispersions present a gel-like behavior and that the presence of AuNP content within microgel matrix contributes to the elasticity of the microgel dispersions. Strain sweep test confirmed that hybrid microgels aqueous dispersion also form colloidal gel structures that break upon deformation but that can be recovered when the deformation decreases. The fractal analysis performed to hybrid microgels, by applying Shih et al. and Wu and Morbidelli's scaling theories, evidenced that AuNP significantly affects the colloidal gel structure configuration ending up with the formation of agglomerates or microgel clusters with closer structures in comparison to the reference P(AAm-co-AAc) aqueous microgel dispersions.
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Affiliation(s)
- Coro Echeverría
- Institute of Polymer Science and Technology (ICTP-CSIC), C/Juan de la Cierva 3, 28006 Madrid, Spain.
| | - Carmen Mijangos
- Institute of Polymer Science and Technology (ICTP-CSIC), C/Juan de la Cierva 3, 28006 Madrid, Spain.
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12
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Minami S, Suzuki D, Urayama K. Rheological aspects of colloidal gels in thermoresponsive microgel suspensions: formation, structure, and linear and nonlinear viscoelasticity. Curr Opin Colloid Interface Sci 2019. [DOI: 10.1016/j.cocis.2019.04.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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13
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Phase-transition induced gelation of ZnO suspensions containing thermosensitive poly(acrylic acid)-graft-poly(N-isopropylacrylamide). ADV POWDER TECHNOL 2019. [DOI: 10.1016/j.apt.2019.04.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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14
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Responsive hydrogel colloids: Structure, interactions, phase behavior, and equilibrium and nonequilibrium transitions of microgel dispersions. Curr Opin Colloid Interface Sci 2019. [DOI: 10.1016/j.cocis.2019.02.005] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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15
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In situ gelation behavior of thermoresponsive poly(N-vinylpyrrolidone)/poly(N-isopropylacrylamide) microgels synthesized by soap-free emulsion polymerization. Polym Bull (Berl) 2018. [DOI: 10.1007/s00289-018-2271-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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