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Polyelectrolyte complexes polyion micelles

Abstract This review reports advances in experimental and theoretical research on interpolyelectrolyte complexes based on polyionic species of star-shaped polyelectrolytes, cylindrical polyelectrolyte brushes, and micelles of ionic amphiphilic block CO- and terpolymers. [Pg.131]

Polyanions and polycations can co-react in aqueous solution to form polyelectrolyte complexes via a process closely linked to self-assembly processes [47]. Despite progresses in the field of (inter-) polyelectrolyte complexes [47] (IPEC from Gohy et al. [48], block ionomer complexes BIC from Kabanov et al. [49], polyion complex PIC from Kataoka and colleagues [50, 51], and complex coacervate core micelles C3M from Cohen Stuart and colleagues [52], understanding of more complex structures such as polyplexes (polyelectrolyte complexes of DNA and polycations) [53] is rather limited [54]. It has also to be considered that the behavior of cationic polymers in the presence of DNA and their complexes can be unpredictable, particularly in physiological environments due to the presence of other polyelectrolytes (i.e., proteins and enzymes) and variations in pH, etc. [Pg.112]

These particles are called by several names in literature block ionomer complexes [57], polyion complex micelles [58], complex coacervate core micelles [59] and polyelectrolyte complex micelles. An extensive review of this type of micelle has been written by Voets et al. [60]. [Pg.152]

Further progress in the field of IPECs has been associated with involvement of more complex polyionic architectures, such as branched ionic (co)polymers (polyelectrolyte stars and cylindrical polyelectrolyte brushes) as well as self-assemblies of linear ionic diblock copolymers (polymeric micelles) (Fig. 6a-c), into interpolyelectrolyte complexation. Synthesis of well-defined polymeric architectures with nonlinear topology has become possible only recently due to considerable developments in living and controlled polymerizations. In this section, we briefly... [Pg.187]

Keywords Polyelectrolyte Co-assembly Responsive Complex coacervate Polyion Micelle... [Pg.65]

PEG-polyelectrolyte block polymers were also found to form polyion complex (PIC) micelles with negatively charged DNA through electrostatic interactions. This is particularity important in the field of gene and DNA/ RNA delivery, as the PIC micelles exhibit an excellent... [Pg.586]

At surfactant concentrations above the equivalent point (>5 x 10 4 mol dm 3) the A curves in the presence of the polyion resemble the behavior of the curve in pine surfactant solutions. They show a break at the so-called apparent critical micellization concentration, cmc [16,42], This term is usually used for characterizing the formation of free surfactant micelles in the presence of the polymeric component. The cmc is higher than the ordinary cmc due to the formation of polyelectrolyte-surfactant complex at lower surfactant concentrations. The bound surfactant ions are not available for... [Pg.818]

Synthesis macrosurfactants, polysoaps, polyelectrolytes as building blocks preparation of spherical, cylindrical, multicompartment, and schizophrenic micelles, polymer vesicles, polyion complexes bottom-up self-assembly stimuli-sensitive colloids... [Pg.35]

When the coordination polymer is mixed with an oppositely charged neutral diblock polymer, the electrostatic interaction will drive complex coacervate formation [40]. But, the growth of the complex coacervate will be constrained by the presence of the neutral blocks, and be stabilized at a finite size. In this way, so-called complex coacervate core micelles (C3Ms), or polyion coacervate (PIC) micelles are formed. This micelle formation is analogous to the formation of C3Ms in covalent polyelectrolyte/ block polymer systems [67, 68]. Obviously, the coordination polymer,... [Pg.105]

Hydrophilic-hydrophilic also called double-hydrophilic block copolymers, consist of water-soluble blocks of different chemical nature. In aqueous solution they behave as unimers like classical polymers or polyelectrolytes, whereas their amphiphilic characteristics, such as surface activity and micelle formation, only appear under the influence of a given external stimuli, mainly temperature, pH or ionic strength changes. Micellization of these copolymers can further be induced by complex formation of one of their blocks, either by electrostatic interaction with oppositely charged polymers, by hydrophobic interactions such as with surfactants, or by insolubilization in the presence of metal derivatives. These polymer intercomplexes, mainly polyion complexes (PIC), with their application possibilities will be outlined in more detail in Section 7.3.13. [Pg.204]

They resemble star-shaped polyelectrolytes with a large number of arms, though the number of arms in such macromolecular self-assemblies might change if the micelles are of dynamic nature, that is, if they are able to change their aggregation numbers with variations in the environmental conditions. Historically, the micelles of ionic amphiphilic diblock copolymers were the first star-like polyionic species involved in interpolyelectrolyte complexation and their IPECs have attracted considerable attention during the recent years. [Pg.193]

In a different context, complex coacervate core micelle can be obtained by the reaction of a polyion-neutral diblock copolymer with an oppositely charged polyelectrolyte. These micelle are formed upon hierarchical self-assembly in water of the two polymeric components and, more interestingly, upon self-assembly of metal ion coordination polymers [47],... [Pg.10]

Chelushkin PS et al (2008) Polyion complex nanomaterials from block polyelectrolyte micelles and linear polyelectrolytes of opposite charge. 2. Dynamic properties. J Phys ChemB 112 7732-7738. doi 10.1021/jp8012877... [Pg.87]

Another interesting system is based on the adsorption of so-called complex coacervate core micelles (also called polyion complex micelles) [28,29]. These micelles are formed in aqueous solution when two oppositely charged polyelectrolytes are mixed, with at least one of these polyelectrolytes being connected to an uncharged and water-soluble polymer. The complexed polyelectrolytes then form the complex coacervate core of the micelles, while the neutral chain forms the corona. These micelles have been shown to adsorb to surfaces with very different properties, such as silica and polystyrene. Although formed brushes are of low density, good antifouling properties have been observed [28,30]. [Pg.136]


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See also in sourсe #XX -- [ Pg.114 , Pg.116 , Pg.122 ]




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Micelles polyelectrolyte

Polyelectrolyte complexes micelles

Polyelectrolytes complexation

Polyion complex micelles

Polyion micelle

Polyion-complexation

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