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Yu X, Li J, Zhang J, Jin J, Pan Y, Ji X, Jiang W. Pathway-dependent Shape Transformation of Polymeric Vesicles under UV Light and the Assembly of UV-irradiated Polymer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024. [PMID: 39105727 DOI: 10.1021/acs.langmuir.4c01995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/07/2024]
Abstract
Shape transformation of polymer particles is generally a nonequilibrium dynamics process. Controlling the shape transformation of polymers is increasingly attractive and challenging for scientists due to their extensive use in drug delivery and cancer therapy. Herein, we investigated the UV-triggered shape transformation pathway of polymeric vesicles assembled from Polystyrene-block-poly(4-vinylpyridine) and 4-hydroxyazobenzene (PS-b-P4VP(Azo-OH)) and the direct assembly pathway of UV-irradiated PS-b-P4VP(Azo-OH) homogeneous solution. In the shape transformation process, well-assembled vesicles can be transformed into toroid, cylindrical, rod-like, and spherical micelles. In the direct assembly pathway, rod-like and spherical micelles can be obtained. Interestingly, the toroid micelles can be obtained only from the UV-triggered shape transformation pathway. Contrasting the two pathways reveals the pathway dependence of PS-b-P4VP(Azo-OH) assembly, suggesting that the final assembly morphology is determined by the initial state and dynamic process. The speed of UV-triggered shape transformation and the final morphology of assemblies can be tuned easily by adjusting the UV illuminance, time, and content of Azo-OH addition. Moreover, the light-responsive polymeric vesicles can be used as drug carriers and have the potential to release drugs precisely.
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Affiliation(s)
- Xin Yu
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
- School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Jinlan Li
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
- School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Jianing Zhang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
- State Key Laboratory of New Textile Materials and Advanced Processing Technologies and Key Laboratory of Textile Fiber and Products of Ministry of Education, College of Materials Science and Engineering, Wuhan Textile University, Wuhan 430200, China
| | - Jing Jin
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
- State Key Laboratory of New Textile Materials and Advanced Processing Technologies and Key Laboratory of Textile Fiber and Products of Ministry of Education, College of Materials Science and Engineering, Wuhan Textile University, Wuhan 430200, China
| | - Yanxiong Pan
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
- School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Xiangling Ji
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
- School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Wei Jiang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
- School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230026, China
- State Key Laboratory of New Textile Materials and Advanced Processing Technologies and Key Laboratory of Textile Fiber and Products of Ministry of Education, College of Materials Science and Engineering, Wuhan Textile University, Wuhan 430200, China
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2
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Zhu Y, Huang C, Zhang L, Andelman D, Man X. The Process-Directed Self-Assembly of Block Copolymer Particles. Macromol Rapid Commun 2023; 44:e2300176. [PMID: 37071857 DOI: 10.1002/marc.202300176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 04/13/2023] [Indexed: 04/20/2023]
Abstract
The kinetic paths of structural evolution and formation of block copolymer (BCP) particles are explored using dynamic self-consistent field theory (DSCFT). It is shown that the process-directed self-assembly of BCP immersed in a poor solvent leads to the formation of striped ellipsoids, onion-like particles and double-spiral lamellar particles. The theory predicts a reversible path of shape transition between onion-like particles and striped ellipsoidal ones by regulating the temperature (related to the Flory-Huggins parameter between the two components of BCP, χAB ) and the selectivity of solvent toward one of the two BCP components. Furthermore, a kinetic path of shape transition from onion-like particles to double-spiral lamellar particles, and then back to onion-like particles is demonstrated. By investigating the inner-structural evolution of a BCP particle, it is identified that changing the intermediate bi-continuous structure into a layered one is crucial for the formation of striped ellipsoidal particles. Another interesting finding is that the formation of onion-like particles is characterized by a two-stage microphase separation. The first is induced by the solvent preference, and the second is controlled by the thermodynamics. The findings lead to an effective way of tailoring nanostructure of BCP particles for various industrial applications.
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Affiliation(s)
- Yanyan Zhu
- Center of Soft Matter Physics and its Applications, School of Physics, Beihang University, Beijing, 100191, China
| | - Changhang Huang
- Center of Soft Matter Physics and its Applications, School of Physics, Beihang University, Beijing, 100191, China
| | - Liangshun Zhang
- Shanghai Key Laboratory of Advanced Polymeric Materials, Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - David Andelman
- School of Physics and Astronomy, Tel Aviv University, Ramat Aviv 69978, Tel Aviv, Israel
| | - Xingkun Man
- Center of Soft Matter Physics and its Applications, School of Physics, Beihang University, Beijing, 100191, China
- Peng Huanwu Collaborative Center for Research and Education, Beihang University, Beijing, 100191, China
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3
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Zhu Q, Tree DR. Simulations of morphology control of self‐assembled amphiphilic surfactants. JOURNAL OF POLYMER SCIENCE 2023. [DOI: 10.1002/pol.20220771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
Affiliation(s)
- Qinyu Zhu
- Department of Chemical Engineering Brigham Young University Provo Utah USA
| | - Douglas R. Tree
- Department of Chemical Engineering Brigham Young University Provo Utah USA
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4
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Feng X, Yan N, Jin J, Jiang W. Disassembly of Amphiphilic AB Block Copolymer Vesicles in Selective Solvents: A Molecular Dynamics Simulation Study. Macromolecules 2023. [DOI: 10.1021/acs.macromol.2c02352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Affiliation(s)
- Xuan Feng
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China
- School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230026, P. R. China
| | - Nan Yan
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China
| | - Jing Jin
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China
| | - Wei Jiang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China
- School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230026, P. R. China
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5
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Xu Z, Dong Q, Zhang L, Li W. Enhanced dielectric permittivity of hierarchically double-gyroid nanocomposites via macromolecular engineering of block copolymers. NANOSCALE 2022; 14:15275-15280. [PMID: 36222383 DOI: 10.1039/d2nr04516h] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
It is a challenging task to realize the periodically bicontinuous gyroid nanostructures of flexible nanocomposites with high loading of functionalized nanoparticles, which could exhibit high dielectric permittivity for energy storage and electronic devices. Herein, with the aid of the concept of macromolecular engineering, we propose novel nanocomposites, composed of A'(A''B)n miktoarm star copolymers and nanoparticles, to obtain a double-gyroid structure through self-consistent field theory coupled with density functional theory. By tailoring the architecture of this copolymer, a large window of the double-gyroid phase extending to a high loading concentration of nanoparticles is achieved, leading to a hierarchical structure of a percolation network of nanoparticles within the gyroid channels. Furthermore, the finite difference quasielectrostatic method is integrated to reveal an enhanced dielectric permittivity of the structured nanocomposites by increasing the loading concentration of nanoparticles. The simultaneous achievement of an ordered double-gyroid phase and high loading nanoparticles represents a crucial step toward the realization of fully three-dimensional network-like metamaterials via a rational molecular design of nanocomposites.
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Affiliation(s)
- Zhanwen Xu
- State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200438, China.
| | - Qingshu Dong
- State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200438, China.
| | - Liangshun Zhang
- Shanghai Key Laboratory of Advanced Polymeric Materials, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China.
| | - Weihua Li
- State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200438, China.
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Li L, Xu Z, Li W. Emergence of Connected Binary Spherical Structures from the Self-assembly of an AB 2C Four-Arm Star Terpolymer. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c01919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Luyang Li
- State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Zhanwen Xu
- State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Weihua Li
- State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
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Müller M. Memory in the relaxation of a polymer density modulation. J Chem Phys 2022; 156:124902. [DOI: 10.1063/5.0084602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Marcus Müller
- Institute for Theoretical Physics, Georg August University Gottingen Faculty of Physics, Germany
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9
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Rottler J, Müller M. Kinetic Pathways of Block Copolymer Directed Self-Assembly: Insights from Efficient Continuum Modeling. ACS NANO 2020; 14:13986-13994. [PMID: 32909745 DOI: 10.1021/acsnano.0c06433] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We introduce a computationally efficient continuum technique to simulate the complex kinetic pathways of block copolymer self-assembly. Subdiffusive chain dynamics is taken into account via nonlocal Onsager coefficients. An application to directed self-assembly of thin films of diblock copolymers on patterned substrates reveals the conditions under which experimentally observed metastable structures intervene in the desired thin-film morphology. The approach generalizes easily to multiblock copolymers and more complex guiding patterns on the substrate, and its efficiency allows for the systematic optimization of guiding patterns and process conditions.
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Affiliation(s)
- Jörg Rottler
- Department of Physics and Astronomy and Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Marcus Müller
- Institute for Theoretical Physics, Georg-August-Universität Göttingen, 37077 Göttingen, Germany
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Qiang Y, Li W, Shi AC. Stabilizing Phases of Block Copolymers with Gigantic Spheres via Designed Chain Architectures. ACS Macro Lett 2020; 9:668-673. [PMID: 35648571 DOI: 10.1021/acsmacrolett.0c00193] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
It is generally believed that the spherical domains self-assembled from AB-type block copolymers are composed of the minority A blocks with a volume fraction of fA < 1/2. Breaking this generic rule so that the spherical domains are formed by the majority A blocks (fA > 1/2) requires mechanisms to drastically expand the stable region of spherical packing phases. Self-consistent field theory predicts that dendron-like AB-type block copolymers, composed of G - 1 generations of A blocks connected with the outermost generation of B blocks, exhibit a stable region of spherical packing phases extending to fA ∼ 0.7. The extremely expanded spherical regions shed light on the mechanisms governing the self-assembly of amphiphilic macromolecules, as well as provide opportunities to engineer complex spherical packing phases.
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Affiliation(s)
- Yicheng Qiang
- State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Weihua Li
- State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - An-Chang Shi
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada
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11
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Müller M. Process-directed self-assembly of copolymers: Results of and challenges for simulation studies. Prog Polym Sci 2020. [DOI: 10.1016/j.progpolymsci.2019.101198] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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12
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Affiliation(s)
- Gaoyuan Wang
- Institute for Theoretical Physics, Georg-August-University, 37077 Göttingen, Germany
| | - Yongzhi Ren
- Institute for Theoretical Physics, Georg-August-University, 37077 Göttingen, Germany
- Key Lab of In-fiber Integrated Optics, Ministry Education of China, Harbin Engineering University, Harbin, China
- State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai, China
| | - Marcus Müller
- Institute for Theoretical Physics, Georg-August-University, 37077 Göttingen, Germany
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Sun DW, Müller M. Numerical algorithms for solving self-consistent field theory reversely for block copolymer systems. J Chem Phys 2018; 149:214104. [PMID: 30525732 DOI: 10.1063/1.5063302] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Besides dictating the equilibrium phase diagram, the rugged free-energy landscape of AB block copolymers gives rise to a multitude of non-equilibrium phenomena. Self-consistent field theory (SCFT) can be employed to calculate the mean-field free energy, F [ ϕ A t a r g e t ] , of a non-equilibrium unstable state that is characterized by a given spatial density distribution, ϕ A t a r g e t , in the incompressible system. Such a free-energy functional is the basis of describing the structure formation by dynamic SCFT techniques or the identification of minimum free-energy paths via the string method. The crucial step consists in computing the external potential fields that generate the given density distribution in the corresponding system of non-interacting copolymers, i.e., the potential-to-density relation employed in equilibrium SCFT calculations has to be inverted (reverse SCFT calculation). We describe, generalize, and evaluate the computational efficiency of two different numerical algorithms for this reverse SCFT calculation-the Debye-function algorithm based on the structure factor and the field-theoretic umbrella-potential (FUP) algorithm. In contrast to the Debye-function algorithm, the FUP algorithm only yields the exact mean-field values of the given target densities in the limit of a strong umbrella potential, and we devise a two-step variant of the FUP algorithm that significantly mitigates this issue. For Gaussian copolymers, the Debye-function algorithm is more efficient for highly unstable states that are far away from the equilibrium, whereas the improved FUP algorithm outperforms the Debye-function algorithm closer to metastable states and is easily transferred to more complex molecular architectures.
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Affiliation(s)
- De-Wen Sun
- Institut für Theoretische Physik, Georg-August-Universität Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen, Germany
| | - Marcus Müller
- Institut für Theoretische Physik, Georg-August-Universität Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen, Germany
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14
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Abetz V, Kremer K, Müller M, Reiter G. Functional Macromolecular Systems: Kinetic Pathways to Obtain Tailored Structures. MACROMOL CHEM PHYS 2018. [DOI: 10.1002/macp.201800334] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Volker Abetz
- Institute of Polymer Research; Helmholtz-Zentrum Geesthacht Max-Planck-Straße 1 21502 Geesthacht Germany
- Institute of Physical Chemistry; University of Hamburg; Martin-Luther-King-Platz 6 20146 Hamburg Germany
| | - Kurt Kremer
- Polymer Theory; Max Planck Institute for Polymer Research; Ackermannweg 10 55128 Mainz Germany
| | - Marcus Müller
- Institute for Theoretical Physics; Georg-August University of Göttingen; Friedrich-Hund-Platz 1 37077 Göttingen Germany
| | - Günter Reiter
- Institute of Physics; Albert-Ludwigs-University of Freiburg; Hermann-Herder-Str. 3 79104 Freiburg Germany
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15
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Affiliation(s)
- De-Wen Sun
- Institut für Theoretische Physik, Georg-August-Universität Göttingen, Friedrich-Hund-Platz 1, D-37077 Göttingen, Germany
| | - Marcus Müller
- Institut für Theoretische Physik, Georg-August-Universität Göttingen, Friedrich-Hund-Platz 1, D-37077 Göttingen, Germany
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16
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Duan C, Zhao M, Qiang Y, Chen L, Li W, Qiu F, Shi AC. Stability of Two-Dimensional Dodecagonal Quasicrystalline Phase of Block Copolymers. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b01638] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Chao Duan
- State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Mingtian Zhao
- State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Yicheng Qiang
- State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Lei Chen
- State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Weihua Li
- State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Feng Qiu
- State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - An-Chang Shi
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada
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Sun T, Liu F, Tang P, Qiu F, Yang Y. Construction of Rod-Forming Single Network Mesophases in Rod–Coil Diblock Copolymers via Inversely Designed Phase Transition Pathways. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b00773] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tongjie Sun
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Faqiang Liu
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Ping Tang
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Feng Qiu
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Yuliang Yang
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
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Schönhöfer PW, Ellison LJ, Marechal M, Cleaver DJ, Schröder-Turk GE. Purely entropic self-assembly of the bicontinuous Ia3d gyroid phase in equilibrium hard-pear systems. Interface Focus 2017; 7:20160161. [PMID: 28630680 PMCID: PMC5474042 DOI: 10.1098/rsfs.2016.0161] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
We investigate a model of hard pear-shaped particles which forms the bicontinuous Ia[Formula: see text]d structure by entropic self-assembly, extending the previous observations of Barmes et al. (2003 Phys. Rev. E68, 021708. (doi:10.1103/PhysRevE.68.021708)) and Ellison et al. (2006 Phys. Rev. Lett.97, 237801. (doi:10.1103/PhysRevLett.97.237801)). We specifically provide the complete phase diagram of this system, with global density and particle shape as the two variable parameters, incorporating the gyroid phase as well as disordered isotropic, smectic and nematic phases. The phase diagram is obtained by two methods, one being a compression-decompression study and the other being a continuous change of the particle shape parameter at constant density. Additionally, we probe the mechanism by which interdigitating sheets of pears in these systems create surfaces with negative Gauss curvature, which is needed to form the gyroid minimal surface. This is achieved by the use of Voronoi tessellation, whereby both the shape and volume of Voronoi cells can be assessed in regard to the local Gauss curvature of the gyroid minimal surface. Through this, we show that the mechanisms prevalent in this entropy-driven system differ from those found in systems which form gyroid structures in nature (lipid bilayers) and from synthesized materials (di-block copolymers) and where the formation of the gyroid is enthalpically driven. We further argue that the gyroid phase formed in these systems is a realization of a modulated splay-bend phase in which the conventional nematic has been predicted to be destabilized at the mesoscale due to molecular-scale coupling of polar and orientational degrees of freedom.
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Affiliation(s)
- Philipp W. A. Schönhöfer
- School of Engineering and Information Technology, Mathematics and Statistics, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia
- Institut für Theoretische Physik I, Universität Erlangen-Nürnberg, Staudtstraße 7, 91058 Erlangen, Germany
| | - Laurence J. Ellison
- Materials and Engineering Research Institute, Sheffield Hallam University, Sheffield S1 1WB, UK
| | - Matthieu Marechal
- Institut für Theoretische Physik I, Universität Erlangen-Nürnberg, Staudtstraße 7, 91058 Erlangen, Germany
| | - Douglas J. Cleaver
- Materials and Engineering Research Institute, Sheffield Hallam University, Sheffield S1 1WB, UK
| | - Gerd E. Schröder-Turk
- School of Engineering and Information Technology, Mathematics and Statistics, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia
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