Self-Assembly of Organometallic Block Copolymers:  The Role of Crystallinity of the Core-Forming Polyferrocene Block in the Micellar Morphologies Formed by Poly(ferrocenylsilane-b-dimethylsiloxane) inn-Alkane Solvents

2000 ◽  
Vol 122 (47) ◽  
pp. 11577-11584 ◽  
Author(s):  
Jason A. Massey ◽  
Karen Temple ◽  
Lan Cao ◽  
Yahya Rharbi ◽  
Jose Raez ◽  
...  
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 ◽  
...  

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).


2018 ◽  
Vol 11 (3) ◽  
pp. 3571-3581 ◽  
Author(s):  
Laura Evangelio ◽  
Marta Fernández-Regúlez ◽  
Jordi Fraxedas ◽  
Marcus Müller ◽  
Francesc Pérez-Murano

Soft Matter ◽  
2009 ◽  
Vol 5 (24) ◽  
pp. 5003 ◽  
Author(s):  
Rina Shvartzman-Cohen ◽  
Chun-lai Ren ◽  
Igal Szleifer ◽  
Rachel Yerushalmi-Rozen

2016 ◽  
Vol 16 (4) ◽  
pp. 4239-4246
Author(s):  
Zhijiao Dong ◽  
Bingbing Yang ◽  
Zhifeng Fu ◽  
Yan Shi

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.


Langmuir ◽  
2003 ◽  
Vol 19 (20) ◽  
pp. 8144-8147 ◽  
Author(s):  
Raffaele Mezzenga ◽  
Janne Ruokolainen ◽  
Alexander Hexemer

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2265
Author(s):  
Xiaoqian Yu ◽  
Artjom Herberg ◽  
Dirk Kuckling

Micellar catalysts with a switchable core are attractive materials in organic synthesis. However, little is known about the role of the shell forming block on the performance of the catalyst. Thermoresponsive block copolymers based on poly(N-isopropylacrylamide-co-vinyl-4,4-dimethylazlactone) attached to different permanently hydrophilic blocks, namely poly(ethylene glycol), poly(N,N-dimethylacrylamide), and poly(2,3-dihydroxypropyl acrylate), were successfully synthesized via reversible addition/fragmentation chain transfer radical polymerization (RAFT). Post-polymerization attachment of an amino-functionalized L-prolineamide using the azlactone ring-opening reaction afforded functionalized thermoresponsive block copolymers. Temperature-induced aggregation of the functionalized block copolymers was studied using dynamic light scattering. It was shown that the chemical structure of the permanently hydrophilic block significantly affected the size of the polymer self-assemblies. The functionalized block copolymers were subjected to an aldol reaction between p-nitrobenzaldehyde and cyclohexanone in water. Upon temperature-induced aggregation, an increase in conversion was observed. The enantioselectivity of the polymer-bound organocatalyst improved with an increasing hydrophilic/hydrophobic interface as a result of the different stability of the polymer aggregates.


Soft Matter ◽  
2021 ◽  
Author(s):  
Mazarine Houbrechts ◽  
Lucas Caire da Silva ◽  
Anitha Ethirajan ◽  
Katharina Landfester

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,...


2021 ◽  
Author(s):  
Shaofei Song ◽  
Jingjie Jiang ◽  
Ehsan Nikbin ◽  
Jane Howe ◽  
Ian Manners ◽  
...  

Self-assembly of crystalline-coil block copolymers (BCPs) in selective solvents is often carried out by heating the mixture until the sample appears to dissolve and then allowing the solution to cool...


2019 ◽  
Vol 55 (59) ◽  
pp. 8595-8598 ◽  
Author(s):  
Santu Bera ◽  
Elad Arad ◽  
Lee Schnaider ◽  
Shira Shaham-Niv ◽  
Valeria Castelletto ◽  
...  

Here we report the influence of amino acid sequence order on the self-assembly and biological functions of the core recognition motif of Amyloid β.


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