A Simple Scaling for the Core−Shell Nanostructure Formed by Self-Assembly of Block Copolymers in a Selective Solvent

2000 ◽  
Vol 33 (2) ◽  
pp. 645-646 ◽  
Author(s):  
Chi Wu ◽  
Jun Gao
Keyword(s):  
Block Copolymers ◽  
Self Assembly ◽  
Core Shell ◽  
Selective Solvent ◽  
The Core ◽  
Simple Scaling

scholarly journals Cylindrical Micelles by the Self-Assembly of Crystalline-b-Coil Polyphosphazene-b-P2VP Block Copolymers. Stabilization of Gold Nanoparticles

Molecules ◽  
2019 ◽  
Vol 24 (9) ◽  
pp. 1772 ◽  
Author(s):  
Maria de los Angeles Cortes ◽  
Raquel de la Campa ◽  
Maria Luisa Valenzuela ◽  
Carlos Díaz ◽  
Gabino A. Carriedo ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Block Copolymers ◽  
Self Assembly ◽  
Cationic Polymerization ◽  
The Self ◽  
The Novel ◽  
Selective Solvent ◽  
The Core ◽  
Cylindrical Micelles ◽  
Main Factor

During the last number of years a variety of crystallization-driven self-assembly (CDSA) processes based on semicrystalline block copolymers have been developed to prepare a number of different nanomorphologies in solution (micelles). We herein present a convenient synthetic methodology combining: (i) The anionic polymerization of 2-vinylpyridine initiated by organolithium functionalized phosphane initiators; (ii) the cationic polymerization of iminophosphoranes initiated by –PR2Cl2; and (iii) a macromolecular nucleophilic substitution step, to prepare the novel block copolymers poly(bistrifluoroethoxy phosphazene)-b-poly(2-vinylpyridine) (PTFEP-b-P2VP), having semicrystalline PTFEP core forming blocks. The self-assembly of these materials in mixtures of THF (tetrahydrofuran) and 2-propanol (selective solvent to P2VP), lead to a variety of cylindrical micelles of different lengths depending on the amount of 2-propanol added. We demonstrated that the crystallization of the PTFEP at the core of the micelles is the main factor controlling the self-assembly processes. The presence of pyridinyl moieties at the corona of the micelles was exploited to stabilize gold nanoparticles (AuNPs).

scholarly journals Formation of Giant Polymer Vesicles by Simple Double Emulsification using Block Copolymers as the Sole Surfactant

Soft Matter ◽  
2021 ◽  
Author(s):  
Mazarine Houbrechts ◽  
Lucas Caire da Silva ◽  
Anitha Ethirajan ◽  
Katharina Landfester
Keyword(s):  
Block Copolymers ◽  
Self Assembly ◽  
Shell Structure ◽  
The Self ◽  
Amphiphilic Block Copolymers ◽  
Core Shell ◽  
The Core ◽  
Polymer Vesicles ◽  
Core Shell Structure ◽  
Double Emulsification

Polymer vesicles that mimic the function of cell membranes can be obtained through the self-assembly of amphiphilic block copolymers. The cell-like characteristics of polymer vesicles, such as the core-shell structure,...

Synthesis of Cationic Amphiphilic Block Copolymers Poly(4-vinylbenzyltriethylammonium chloride)-b-Poly(styrene) and Their Self-Assembly in Aqueous Solution

2016 ◽  
Vol 16 (4) ◽  
pp. 4239-4246
Author(s):  
Zhijiao Dong ◽  
Bingbing Yang ◽  
Zhifeng Fu ◽  
Yan Shi
Keyword(s):  
Block Copolymers ◽  
Formation Process ◽  
Self Assembly ◽  
Chain Transfer ◽  
Amphiphilic Block Copolymers ◽  
The Core ◽  
Reversible Addition ◽  
The Common ◽  
Spherical Micelles ◽  
Large Compound

Well defined two kinds of cationic amphiphilic block copolymers Poly(4-vinylbenzyltriethylammonium chloride)-b-Poly(styrene) are synthesized by combining reversible addition fragmentation chain transfer polymerizations and post-polymerization quaternization. Block copolymers are characterized by GPC and 1HNMR. The self-assembly behaviors of the block copolymers are studied, which are characterized by TEM. For Poly(4-vinylbenzyltriethylammonium chloride)13-b-Poly(styrene)136, crew-cut spherical micelles are obtained by using DMF as the initial common solvent, and the majority of the pearl series aggregates and a small amount of rod-like aggregates are all observed by using the mixture of DMF and THF as the initial common solvent. The formation process of rod-like aggregates is proposed in three steps: the micellization of copolymer chains, the formation of pearl series aggregates from the collision and fusion of individual initial spherical micelles, and the transformation from pearl series aggregates to rod-like aggregates. For Poly(4- vinylbenzyltriethylammonium chloride)18-b-Poly(styrene)370, large compound micelles and complicated spherical aggregates and small vesicles are all obtained. The formation process of small vesicles is also proposed in three steps: the formation of initial spherical micelles with some hydrophilic block Poly(4-vinylbenzyltriethylammonium chloride) embedded in the core, the removing of the outer layer common solvent, and solvent nucleation in the center. It should be noted that solvent nucleation is critical, because of the hydrophilic block Poly(4-vinylbenzyltriethylammonium chloride) and the common solvent and water embedded in the core of the initial spherical micelles.

Self-Assembly of Poly(ferrocenyldimethylsilane-b-methyl methacrylate) Block Copolymers in a Selective Solvent

2006 ◽  
Vol 39 (6) ◽  
pp. 2306-2315 ◽  
Author(s):  
Igor Korczagin ◽  
Mark A. Hempenius ◽  
Remco G. Fokkink ◽  
Martien A. Cohen Stuart ◽  
Mahmoud Al-Hussein ◽  
...  
Keyword(s):  
Block Copolymers ◽  
Methyl Methacrylate ◽  
Self Assembly ◽  
Selective Solvent

scholarly journals Complementary Nucleobase Interactions Drive the Hierarchical Self-Assembly of Core–Shell Bottlebrush Block Copolymers toward Cylindrical Supramolecules

2020 ◽  
Vol 53 (22) ◽  
pp. 9747-9757
Author(s):  
Spyridon Varlas ◽  
Zan Hua ◽  
Joseph R. Jones ◽  
Marjolaine Thomas ◽  
Jeffrey C. Foster ◽  
...  
Keyword(s):  
Block Copolymers ◽  
Self Assembly ◽  
Core Shell

scholarly journals Characterizing the Core-Shell Architecture of Block Copolymer Nanoparticles with Electron Microscopy: A Multi-Technique Approach

Polymers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1656
Author(s):  
Vitalii Tkachenko ◽  
Loïc Vidal ◽  
Ludovic Josien ◽  
Marc Schmutz ◽  
Julien Poly ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Block Copolymer ◽  
Self Assembly ◽  
Morphological Characterization ◽  
Spherical Particles ◽  
Core Shell ◽  
Positive Staining ◽  
Particle Volume ◽  
Core Diameter ◽  
The Core

Electron microscopy has proved to be a major tool to study the structure of self-assembled amphiphilic block copolymer particles. These specimens, like supramolecular biological structures, are problematic for electron microscopy because of their poor capacity to scatter electrons and their susceptibility to radiation damage and dehydration. Sub-50 nm core-shell spherical particles made up of poly(hydroxyethyl acrylate)–b–poly(styrene) are prepared via polymerization-induced self-assembly (PISA). For their morphological characterization, we discuss the advantages, limitations, and artefacts of TEM with or without staining, cryo-TEM, and SEM. A number of technical points are addressed such as precisely shaping of particle boundaries, resolving the particle shell, differentiating particle core and shell, and the effect of sample drying and staining. TEM without staining and cryo-TEM largely evaluate the core diameter. Negative staining TEM is more efficient than positive staining TEM to preserve native structure and to visualize the entire particle volume. However, no technique allows for a satisfactory imaging of both core and shell regions. The presence of long protruding chains is manifested by patched structure in cryo-TEM and a significant edge effect in SEM. This manuscript provides a basis for polymer chemists to develop their own specimen preparations and to tackle the interpretation of challenging systems.

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