Micelles core-shell-corona

Core-shell-corona micelles were formed by PEHA-PMMA-PAA triblock copolymers in water, as demonstrated by Kriz et al. [266]. Ishizone et al. [267] synthesized ABC triblock copolymers containing 2-(perfluorobutyl)ethyl methacrylate, tBMA, and 2-(trimethylsilyloxy) ethyl methacrylate with various block sequences. These copolymers were converted into amphiphilic sys-... 

Fig. 18 Schematical representation of different types of micelles formed by ABC triblock copolymers. Core-shell-corona micelles with insoluble core and shell (a), core-shell-corona micelles with radially compartmentalized corona (b), and Janus micelles with laterally compartmentalized corona (c)...

Temperature- and pH-sensitive core-shell-corona micelles were also recently reported by Armes et al. Moreover, the shell of these CSC micelles could be selectively cross-linked [275]. 

For some applications, it is desirable to lock the micellar structure by cross-Hnking one of the micellar compartments, as discussed previously in Sect. 2.6. Cross-Hnked core-shell-corona micelles have been prepared and investigated by several groups as illustrated by the work of Wooley and Ma [278], who reported the cross-linking of PS-PMA-PAA micelles in aqueous solution by amidation of the PAA shell. Very recently, Wooley et al. prepared toroidal block copolymer micelles from similar PS-PMA-PAA copolymers dissolved in a mixture of water, THF, and 2,2-(ethylenedioxy)diethylamine [279]. Under optimized conditions, the toroidal phase was the predominant structure of the amphiphilic triblock copolymer (Fig. 19). The collapse of the negatively charged cylindrical micelles into toroids was found to be driven by the divalent 2,2-(ethylenedioxy)diethylamine cation. 

ABC triblock copolymers have recently proven to be useful in constructing the so-called three-layer, onion, or core-shell-corona micelles, as described in Sect. 7.2. These micelles are characterized by a centrosymmetric structure and a micellar core with two different concentric compartments. Noncentrosymmetric structures from ABC triblock copolymers blended with AC diblocks have, however, been reported in bulk by Goldacker et al. [290]. 

Covalent and metallosupramolecular block copolymers have been combined in a single macromolecular structure. In this respect a terpyridine-functionalized PS-P2 VP has been complexed with a terpyridine-functionalized PEO, leading to a PS32-P2VPi3-[Ru]-PE07o ABC triblock copolymer [330]. This copolymer was further used to prepare core-shell-corona micelles consisting of a PS core, a pH-responsive P2VP shell, and a PEO corona. 

Fig. 4 Representation of the various types of internal organisation that may occur in micelles formed through co-assembly of charged block copolymers. Depicted are micelles with a corona consisting of two different neutral monomers (shown in blue and green) that are (a) mixed, (b) laterally segregated, (c) radially segregated, and (d) laterally and radially segregated. Both cen-trosymmetric micelles (a, c) and non-centrosymmetiic micelles (b, d) are depicted. The micelle with a laterally segregated corona is generally referred to as a Janus micelle (b). The micelle depicted in (c) is most commonly known as onion-like or core-shell-corona micelle. The micelle with a laterally and radially segregated corona (d) is usually called a patched micelle. Note that in the case of (c) and (d) the blue and the red/black chains may also switch position...

As introduced previously, onion-like or core-shell-corona micelles were also reported in complexes formed via... 

Wang YC, Li Y, Sun TM, Xiong MH, Wu J, Yang YY, Wang J (2010) Core-shell-corona micelle stabilized by reversible cross-linkage for intracellular diug delivery. Macromol Rapid Common 31 1201-1206... 

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