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Gupta S, Chatterjee S, Zolnierczuk P, Nesterov EE, Schneider GJ. Impact of Local Stiffness on Entropy Driven Microscopic Dynamics of Polythiophene. Sci Rep 2020; 10:9966. [PMID: 32561777 PMCID: PMC7305133 DOI: 10.1038/s41598-020-66354-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 05/19/2020] [Indexed: 11/09/2022] Open
Abstract
We exploited the high temporal and spatial resolution of neutron spin echo spectroscopy to investigate the large-scale dynamics of semiflexible conjugated polymer chains in solutions. We used a generalized approach of the well-established Zimm model of flexible polymers to describe the relaxation mode spectra of locally stiff polythiophene chains. The Zimm mode analysis confirms the existence of beads with a finite length that corresponds to a reduced number of segmental modes in semiflexible chains. Irrespective of the temperature and the molecular weight of the conjugated polymer, we witness a universal behavior of the local chain stiffness and invariability of the bead length. Our experimental findings indicate possibly minor role of the change in π-electron conjugation length (and therefore conjugated backbone planar to non-planar conformational transition) in the observed thermochromic behavior of polythiophene but instead point on the major role of chain dynamics in this phenomenon. We also obtained the first experimental evidence of an existence of a single-chain glass state in conjugated polymers.
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Affiliation(s)
- Sudipta Gupta
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA.
| | - Sourav Chatterjee
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Piotr Zolnierczuk
- Jülich Centre for Neutron science (JCNS) and outstation at SNS, POB 2008, 1 Bethel Valley Road, TN, 37831, Oak Ridge, USA
| | - Evgueni E Nesterov
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA. .,Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, IL, 60115, USA.
| | - Gerald J Schneider
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA. .,Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA, 70803, USA.
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2
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Geng J, Song H, Gao F, Kong Y, Fu J, Luo J, Yang Y, Yu C. Lyophilization enabled disentanglement of polyethylenimine on rambutan-like silica nanoparticles for enhanced plasmid DNA delivery. J Mater Chem B 2020; 8:4593-4600. [PMID: 32391536 DOI: 10.1039/d0tb00720j] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Polyethylenimine (PEI) functionalization onto nanoparticles is a widely used strategy for constructing particulate vectors for gene delivery. However, how to control the conformation of PEI chains and the resultant impact on gene transfection efficiency remains largely unexplored. Herein, we report that drying methods dramatically affect the conformation of PEI chains modified on the surface of silica nanoparticles and consequently the plasmid DNA transfection performance. Specifically, lyophilization renders less entangled PEI compared to commonly used vacuum drying as evidenced by an elevated glass transition temperature. The lyophilization induced disentangled conformation is likely associated with the solid-to-gas phase transition drying mechanism, which removes the bound crystal water content and thus reduces hydrogen bonding between amines. Moreover, we find that the stretched PEI chains on the surface of rambutan-like silica nanoparticles promote their binding capacity towards plasmid DNA molecules and thereby enhanced gene delivery and transfection efficiency. Our findings have provided new understanding about amine based polymers modified on nanoparticles, and have significant implications on the design of efficient particulate vectors for gene delivery.
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Affiliation(s)
- Jing Geng
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD 4072, Australia.
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3
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Li Y, Lin D, Xu J, Zhou X, Zuo B, Tsui OKC, Zhang W, Wang X. Glass transition temperature of single-chain polystyrene particles end-grafted to oxide-coated silicon. J Chem Phys 2020; 152:064904. [PMID: 32061204 DOI: 10.1063/1.5140627] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
A method based on the PeakForce QNM atomic force microscopic (AFM) adhesion measurement is employed to investigate the glassy dynamics of polystyrene (PS) single-chain particles end-grafted to SiO2-Si substrates with different diameters, D0, of 3.4 nm-8.8 nm and molar masses, Mn, of 8-123 kg/mol. As temperature was increased, the adhesion force, Fad, experienced by the AFM tip on pulling off the single chains after loading demonstrated a stepwise increase at an elevated temperature, which we identified to be Tg based on previous works. Our result shows that Tg of our grafted single chains increases with Mn in a manner consistent with the Fox-Flory equation, but the coefficient quantifying the Mn dependence of Tg is only (36 ± 6)% the value of bulk PS. In addition, the value of Tg in the Mn → ∞ limit is about 25 °C below the bulk Tg but more than 15 °C above that of (untethered) PS nanoparticles with D0 ≈ 100 nm suspended in a solution. Our findings are consistent with Tg of our single chains being dominated by simultaneous effects of the interfaces, which depress Tg, and end-grafting, which enhances Tg. The latter is believed to exert its influence on the glass transition dynamics by a mechanism reliant on chain connectivity and does not vary with chain length.
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Affiliation(s)
- Yawei Li
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Decai Lin
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Jianquan Xu
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Xianjing Zhou
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Biao Zuo
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Ophelia K C Tsui
- Department of Physics, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Wei Zhang
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Xinping Wang
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
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4
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Pawlak A. The Entanglements of Macromolecules and Their Influence on the Properties of Polymers. MACROMOL CHEM PHYS 2019. [DOI: 10.1002/macp.201900043] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Andrzej Pawlak
- Centre of Molecular and Macromolecular StudiesPolish Academy of Sciences Sienkiewicza 112 90‐363 Lodz Poland
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5
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Su X, Chen B. Tough, resilient and pH-sensitive interpenetrating polyacrylamide/alginate/montmorillonite nanocomposite hydrogels. Carbohydr Polym 2018; 197:497-507. [DOI: 10.1016/j.carbpol.2018.05.082] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2018] [Revised: 05/14/2018] [Accepted: 05/28/2018] [Indexed: 10/14/2022]
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6
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A facile physical approach to make chitosan soluble in acid-free water. Int J Biol Macromol 2017; 103:575-580. [DOI: 10.1016/j.ijbiomac.2017.05.066] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Revised: 04/29/2017] [Accepted: 05/15/2017] [Indexed: 11/21/2022]
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7
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Su X, Mahalingam S, Edirisinghe M, Chen B. Highly Stretchable and Highly Resilient Polymer-Clay Nanocomposite Hydrogels with Low Hysteresis. ACS APPLIED MATERIALS & INTERFACES 2017; 9:22223-22234. [PMID: 28609609 DOI: 10.1021/acsami.7b05261] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Highly stretchable and highly resilient polymer-clay nanocomposite hydrogels were synthesized by in situ polymerization of acrylamide in the presence of pristine montmorillonite (MMT) or chitosan-treated MMT nanoplatelets at an elevated temperature. Both nanocomposite hydrogels can be stretched to a strain of no less than 1290%. The treatment of clay with chitosan improves the tensile strength, elongation at break, and energy at break of the nanocomposite hydrogel by 237%, 102%, and 389%, respectively, due to the strong chitosan-MMT electrostatic interaction and the grafting of polyacrylamide onto chitosan chains. Both hydrogels display excellent resilience with low hysteresis; with a maximum tensile strain of 50%, ultralow hysteresis is found, while, with a maximum strain of 500%, both hydrogels fully recover their original state in just 1 min. The superb resilience of the nanocomposite hydrogels is attributed to the strong interactions within the hydrogels brought by chain branching, multiple hydrogen bonding, covalent bonding, and/or electrostatic force. The hydrogels can be fabricated into different shapes and forms, including microfibers spun using pressurized gyration, which may find a variety of potential applications in particular in healthcare.
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Affiliation(s)
- Xing Su
- Department of Materials Science and Engineering, University of Sheffield , Mappin Street, Sheffield S1 3JD, United Kingdom
| | - Suntharavathanan Mahalingam
- Department of Mechanical Engineering, University College London , Torrington Place, London WC1E 7JE, United Kingdom
| | - Mohan Edirisinghe
- Department of Mechanical Engineering, University College London , Torrington Place, London WC1E 7JE, United Kingdom
| | - Biqiong Chen
- Department of Materials Science and Engineering, University of Sheffield , Mappin Street, Sheffield S1 3JD, United Kingdom
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8
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Zuo B, Liu Y, Liang Y, Kawaguchi D, Tanaka K, Wang X. Glass Transition Behavior in Thin Polymer Films Covered with a Surface Crystalline Layer. Macromolecules 2017. [DOI: 10.1021/acs.macromol.6b02740] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Biao Zuo
- Department
of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing
Technology of Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018, P. R. China
| | - Yue Liu
- Department
of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing
Technology of Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018, P. R. China
| | - Yongfeng Liang
- Department
of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing
Technology of Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018, P. R. China
| | | | | | - Xinping Wang
- Department
of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing
Technology of Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018, P. R. China
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9
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Wei W, Feng S, Zhou Q, Liang H, Long Y, Wu Q, Gao H, Liang G, Zhu F. Study on glass transition and physical aging of polystyrene nanowires by differential scanning calorimetry. JOURNAL OF POLYMER RESEARCH 2017. [DOI: 10.1007/s10965-017-1199-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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10
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Liu XT, Bao RY, Li YM, Yang W, Xie BH, Yang MB. Effect of chain entanglement on the melt-crystallization behavior of poly(l-lactide) acid. JOURNAL OF POLYMER RESEARCH 2016. [DOI: 10.1007/s10965-016-1060-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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11
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Volynskii AL, Yarysheva AY, Rukhlya EG, Yarysheva LM, Bakeev NF. Effect of spatial restrictions at the nanometer scale on structuring in glassy and crystalline polymers. POLYMER SCIENCE SERIES A 2015. [DOI: 10.1134/s0965545x15050168] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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12
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Lu XL, Mi YL. Glass transition behavior of spin-coated thin films of a hydrophilic polymer on supported substrates. CHINESE JOURNAL OF POLYMER SCIENCE 2015. [DOI: 10.1007/s10118-015-1612-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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13
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Entropy reduction phenomenon in the non-equilibrium state of freeze-dried polymethyl methacrylate samples. JOURNAL OF POLYMER RESEARCH 2014. [DOI: 10.1007/s10965-014-0392-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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14
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Chen R, Cao C, Huang D. Visualization and Characterization of Discontinuous Particle Films of Polystyrene by Atomic Force Microscopy. J MACROMOL SCI B 2013. [DOI: 10.1080/00222348.2011.629895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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15
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Guo Y, Morozov A, Schneider D, Chung JW, Zhang C, Waldmann M, Yao N, Fytas G, Arnold CB, Priestley RD. Ultrastable nanostructured polymer glasses. NATURE MATERIALS 2012; 11:337-43. [PMID: 22306770 DOI: 10.1038/nmat3234] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Accepted: 12/22/2011] [Indexed: 05/08/2023]
Abstract
Owing to the kinetic nature of the glass transition, the ability to significantly alter the properties of amorphous solids by the typical routes to the vitreous state is restricted. For instance, an order of magnitude change in the cooling rate merely modifies the value of the glass transition temperature (T(g)) by a few degrees. Here we show that matrix-assisted pulsed laser evaporation (MAPLE) can be used to form ultrastable and nanostructured glassy polymer films which, relative to the standard poly(methyl methacrylate) glass formed on cooling at standard rates, are 40% less dense, have a 40 K higher T(g), and exhibit a two orders of magnitude enhancement in kinetic stability at high temperatures. The unique set of properties of MAPLE-deposited glasses may make them attractive in technologies where weight and stability are central design issues.
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Affiliation(s)
- Yunlong Guo
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, USA
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16
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Chen R, Huang D. Preparation of polymer nanoparticles, and the effect of nanoconfinement on glass transition, structural relaxation and crystallization. ACTA ACUST UNITED AC 2012. [DOI: 10.1007/s11458-011-0262-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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17
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Yang J, Han CR, Duan JF, Ma MG, Zhang XM, Xu F, Sun RC, Xie XM. Studies on the properties and formation mechanism of flexible nanocomposite hydrogels from cellulose nanocrystals and poly(acrylic acid). ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm35498e] [Citation(s) in RCA: 122] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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18
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Lu X, Xue G, Mi Y. Understanding the effect of chain entanglement on the glass transition of a hydrophilic polymer. J Appl Polym Sci 2010. [DOI: 10.1002/app.32963] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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19
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Stefanescu EA, Stefanescu C, Negulescu II. Biodegradable Polymeric Capsules Obtained via Room Temperature Spray Drying: Preparation and Characterization. J Biomater Appl 2010; 25:825-49. [DOI: 10.1177/0885328210366489] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The aim of this contribution is to determine the relationship existent between the chemistry and/or viscosity of some biodegradable polymer solutions and the morphology of micro- and nanospheres resulted after spray drying the solutions at room conditions either in the presence or in the absence of an encapsulated aqueous material. Using dichloromethane as solvent, the following polyesters were used to prepare 2 wt% solutions: polyhydroxybutyrate (PHB), polylactic acid (PLA), poly(lactic- co-glycolic acid) (PLGA) and Eastar Bio GP (GP). A comprehensive thermal characterization was also performed on all polymers to verify the relationships existent between the structure of polyesters and certain important parameters, such as Tg, T m, Td. It was observed that a decrease in the solution viscosity triggers the formation of smoother microspheres. When the viscosity becomes low enough the sprayed solution can lead to the development of well defined nanospheres instead of microspheres. Additionally, it was found that in the presence of an aqueous core the micro- and/or nanocapsules coalesce into larger micrometric aggregates, due to the plasticizing effects of water on the polyester.
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Affiliation(s)
- Eduard A. Stefanescu
- Department of Materials Science and Engineering Iowa State University, Ames, IA 50011, USA,
| | - Cristina Stefanescu
- Department of Chemistry, Louisiana State University Baton Rouge, LA 70803, USA
| | - Ioan I. Negulescu
- School of Human Ecology, Agricultural Center Louisiana State University, Baton Rouge, LA 70803, USA
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Al-Obaidi H, Brocchini S, Buckton G. Anomalous properties of spray dried solid dispersions. J Pharm Sci 2009; 98:4724-37. [DOI: 10.1002/jps.21782] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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21
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Tonelli AE. Organizational stabilities of bulk neat and well-mixed, blended polymer samples coalesced from their crystalline inclusion compounds formed with cyclodextrins. ACTA ACUST UNITED AC 2009. [DOI: 10.1002/polb.21753] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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22
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Chen W, Jiang W, Tao F, Xue G, Liu X. Structural Relaxation of Polystyrene Glasses with Dis‐interpenetrated Chains Studied by Differential Scanning Calorimetry. J MACROMOL SCI B 2008. [DOI: 10.1080/00222340802118986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Wei Chen
- a Department of Polymer Science and Engineering , Nanjing University, The State Key Laboratory of Coordination Chemistry , Nanjing, China
| | - Wei Jiang
- a Department of Polymer Science and Engineering , Nanjing University, The State Key Laboratory of Coordination Chemistry , Nanjing, China
| | - Fangfang Tao
- a Department of Polymer Science and Engineering , Nanjing University, The State Key Laboratory of Coordination Chemistry , Nanjing, China
| | - Gi Xue
- a Department of Polymer Science and Engineering , Nanjing University, The State Key Laboratory of Coordination Chemistry , Nanjing, China
| | - Xiaoning Liu
- b College of Life Science and Pharmaccutical Engineering , Nanjing University of Technology , Nanjing, Jiangsu, China
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23
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Zheng W, Simon S. Polystyrene freeze-dried from dilute solution: Tg depression and residual solvent effects. POLYMER 2006. [DOI: 10.1016/j.polymer.2006.03.035] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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24
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Uyar T, Rusa CC, Hunt MA, Aslan E, Hacaloglu J, Tonelli AE. Reorganization and improvement of bulk polymers by processing with their cyclodextrin inclusion compounds. POLYMER 2005. [DOI: 10.1016/j.polymer.2005.04.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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25
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Yin W, Yang H, Cheng R. Glass transition of the two distinct single-chain particles of poly(N-isopropylacrylamide). THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2005; 17:1-5. [PMID: 15827689 DOI: 10.1140/epje/i2004-10113-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2004] [Accepted: 03/05/2005] [Indexed: 05/24/2023]
Abstract
Two distinct single-chain particles of poly(N-isopropylacrylamide) (PNIPAM) in the state of loose coil and compact globule, have been prepared successfully below and above the lower critical solution temperature (LCST) in extreme dilute aqueous solution by the freeze-drying method, respectively. During the preparation of the compact globular single-chain sample, the surfactant of sodium n-dodecyl sulfate (SDS) was added into the system to prevent aggregation of globular single chains formed at a temperature above the LCST. After all the coil has been transformed into the compact globular particle, the SDS molecules were removed by dialysis. The glass transition temperature (T(g)) of the two single-chain samples has been measured by differential scanning calorimetery (DSC) in comparison with that of bulk polymer. It was found that the T(g) of the single-chain sample in compact-globule state was very near to that of the bulk polymer, whereas the T(g) of the single-chain sample in loose-coil state was approximately 6 K lower than that of the bulk polymer. After treating the sample with repeated DSC cycles, the T(g) of the single-chain sample in loose-coil state rose up successively near to that of the bulk polymer. These results have been explained in terms of the effect of entanglement on the mobility of the polymer segments in the two distinct single-chain samples.
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Affiliation(s)
- Weisi Yin
- Key Laboratory of Mesoscopic Chemistry of MOE and Department of Polymer Science & Engineering, College of Chemistry & Chemical Engineering, Nanjing University, Jiangsu, 210093, Nanjing, PRC
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Rong W, Fan Z, Yu Y, Bu H, Wang M. Influence of entanglements on glass transition of atactic polystyrene. ACTA ACUST UNITED AC 2005. [DOI: 10.1002/polb.20513] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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27
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Sasaki T, Yamauchi N, Irie S, Sakurai K. Differential scanning calorimetry study on thermal behaviors of freeze-dried poly(L-lactide) from dilute solutions. ACTA ACUST UNITED AC 2004. [DOI: 10.1002/polb.20314] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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28
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Simon S, Bernazzani P, McKenna G. Effects of freeze-drying on the glass temperature of cyclic polystyrenes. POLYMER 2003. [DOI: 10.1016/j.polymer.2003.10.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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