Block copolymers self-organization

As you might guess, if you go on to consider things like triblock copolymers, the number of possible structures becomes very large, but we won t go there. Instead, we will conclude this section by briefly considering why block copolymers self-organize in the first place. 

Amphiphilic block copolymers self-organize in aqueous mixtures to form polymeric micelles having a core of the hydrophobic block and a shell of the hydrophilic block. The cores can absorb additional hydrophobic low molecular weight compounds. The shells can be cross-linked to form capsules that are much more physically robust than the original micelles, as shown in Figure 11.10 (15). The uncross-linked inner phase can be dissolved by a good solvent to produce hollow capsules or serve as a site for trapping metal nanoparticles as catalysts. 

Morphology of Block Copolymers — Self-Organized Polymers . 

Keywords Supramolecular system Block copolymer Self-assembled system Inclusion complexes Cyclodextrin Air-water interface Non-covalent interaction Auto-organization... 

Block copolymers self-assemble to form nanoscale organized structures in a selective solvent. The most common structures are spheres, with the insoluble core surrounded by a solvent-swollen corona. In some instances, disk- or worm-like micelles form, and are of particular interest, since the control of their association can lead to a broad range of new applications [1,2]. An important subset of block copolymer micelles are those which contain metal atoms, through covalent attachment or by complexa-tion [3], These structures are interesting because they take advantage of the intrinsic properties of their components, such as the mechanical properties of the polymer micelles and the optical and magnetic characteristics of the metal atoms. Moreover, the assembly permits the control of the uniformity in size and shape of the nanoparticles, and it stabilizes them. 

Cheyne RB, Moffitt MG (2007) Controllable organization of quantum dots into mesoscale wires and cables via interfacial block copolymer self-assembly. Macromolecules 40(6) 2046-2057... 

Leclere, R, et al. 1998. Organized semiconducting nanostructures from conjugated block copolymer self-assembly. Chem Mater 10 4010. 

TirreU, M. (1996) Block copolymer self-assembly at surfaces structure and properties. In S.E. Webber, P. Munk and Z. Tuzar (eds). Solvents and Self-organization of Polymer, NATO ASI Series, Serie E Applied Sciences Vol. 327. Kluwer Academic Publisher, Dordrecht, pp. 281-308. 

Design and Applications of Multiscale Organic-Inorganic Hybrid Materials Derived from Block Copolymer Self-Assembly... 

As these block copolymers were synthesized using the anionic polymerization technique, their molecular weight distributions were narrow. The microspheres with narrower size distribution are better for well-ordered self-organization. Actually, all block copolymers synthesized for these works formed poly(4-vinyl pyridine) (P4VP) spheres in the PS matrices with narrow size distributions. 

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