Diblock copolymers micelles

Tamil S.S., Spatz, J.P., Klok H.A., and Martin M. Gold-polypyrrole core-shell particles in diblock copolymer micells, Aiiv. Mater., 10, 132, 1998. 

Figure 23. Polymer A and polymer B form the diblock copolymer micelles where metal nanoparticles can be grown.

Figure 11.8 Formation of ordered nanoparticles of metal from diblock copolymer micelles, (a) Diblock copolymer (b) metal salt partition to centres of the polymer micelles (c) deposition of micelles at a surface (d) micelle removal and reduction of oxide to metal, (e) AFM image of carbon nanotubes and cobalt catalyst nanoparticles after growth (height scale, 5 nm scan size, lxl pm). [Part (e) reproduced from Ref. 47].

Hu J, Lui G. Chain mixing and segregation in B-C and C-D diblock copolymer micelles. Macromolecules 2005 38 8058-8065. 

Gast and co-workers (Gast 1996 McConnell et al. 1994) used SCFT to study interactions between spherical diblock copolymer micelles in solution.The theory was used to calculate intermicellar pair potentials and combined with liquid-state... 

FIGURE 13.3 Sketch for the structure of a diblock copolymer micelle with a molten liquid core. The core is free of solvent or tail monomers. (Reproduced from Marques, C. M. iaa7ymuir13 1430-1433. VMth permission from American Chemical Society.)... 

The diblock copolymer micelles can be used to prepare inorganic nanoparticles ranging from 1 to 10 nm in diameter [12,30]. In the so-called microreactor approach, the core block, which is shielded by the shell interacts preferentially with the inorganic molecules in solution causing their precipitation inside the micelles. If the inorganic component was a metal salt, the latter could be reduced to a free metal state by either chemical or temperature treatment. The size of thus obtained metal cluster was controlled by the micelle size depending on the... 

In search of easy dispersible nucleating agents with a high number of nucleants per volume, Spitael et al. [19] investigated the use of nanoscale diblock copolymer micelles on the batch-foaming behavior of PS. The diblock copolymers were composed of a PS block, and either PDMS, PEP, or PMMA as a second block. Several factors were identified as essential for nucleation, e.g., the size of the micelle and the surface tension of the micelle core material. 

Fig. 5 Schematic representation of AB diblock copolymer micelles in a selective solvent of the A block, Rc core radius, L shell (corona) thickness. Adapted from Riess [29]. Copyright 2003, with permission from Elsevier...

Zhulina KB, Adam M (2005) Diblock copolymer micelles in a dilute solution. Macromolecules 38 5330-5351... 

Figure 12 TEM images of gold nanoparticles of different size prepared in diblock copolymer micelles, (a) 6nm, (b) 4nm, (c) 2.5 nm. (Reprinted from G. Schmid, D.V. Talapin, E.V. Shevchenko in ed. G. Schmid Nanoparticles. From Theory to Application, Wiley-VCH, Weinheim 2004, with permission from Wiley-VCH)...

The solid dispersion method (Fig. 2B) was used for solubilization of paclitaxel into PEG-poly(D,L-lactide) diblock copolymer micelles. Paclitaxel and the polymer were dissolved in acetonitrile followed by evaporation of the solvent under a stream of nitrogen at 60°C to obtain a gel-like polymer-drug matrix. Dissolution of the solid matrix in water at about 60° C with stirring led to formation of drug-loaded micelles. Because a heating is needed to completely dissolve the polymer-drug matrix, this method may not be not desirable for thermally unstable drugs. 

Fig. 15.14. Shell-crosslinking strategy using partially quaternized PS-b-P4VP diblock copolymer micelles.

Sohn BH et al (2003) Directed self-assembly of two kinds of nanoparticles utilizing monolayer films of diblock copolymer micelles. J Am Chem Soc 125(21) 6368-6369... 

QU1 Quintana, J.R, Janez, M.D, Villacampa, M., and Katime, I., Diblock copolymer micelles in solvent binary mixtures. 1. Selective solvent/piecipitant. Macromolecules, 28, 4139, 1995. 

Pioge, S. Nesterenko, A. Brotons, G. Pascual, S. Fontaine, L. Gaillard, C. Nicol, E. Core cross-linking of dynamic diblock copolymer micelles Quantitative study of photopolymerization efficiency and micelle structure. Macromolecules 2011,44 (3) 594-603. 

Mattice and coworkers performed their simulations of diblock copolymer micellization on a cubic lattice, typically of dimensions 44 x 44 x 44 and with a coordination number of c = 6. As in the case of Larson s model, only one energy parameter, f, is considered for all interactions, namely, the interaction between the tail and the solvophilic (head and solvent) beads. The base structure used for the copolymer is hiQtio. The chains are rearranged using reptation and Verdier-Stockmayer [53] type local motions, both of which are discussed in detail in Sec. III. C. Wijmans and Linse [50] also based their simulations on this model and surfactant structure. 

When the diblock copolymer micelles play a lyophilizing part (i.e., when they act as HPEs), water-soluble micellar IPECs can be typically obtained via at least one of the preparation routes described by the authors [73]. In this case, the chemical... 

First, we studied the solvent relaxation in solutions of diblock copolymer micelles. A commercially available polarity-sensitive probe, patman (Fig. 10, structure I), frequently used in phospolipid bilayer studies [123], was added to aqueous solutions of PS-PEO micelles. The probe binds strongly to micelles because its hydrophobic aliphatic chain has a strong affinity to the nonpolar PS core. The positively charged fluorescent headgroup is supposed to be located in the PEO shell close to the core-shell interface. The assumed localization has been supported by time-resolved anisotropy measurements. 

Other examples of such detailed analysis of the structure with the aid of contrast variation can be found for partially deuterated polystyrene-polyisoprene (PS-Pl) diblock copolymer micelles in decane [86, 95] Pluronic (PEO-PPO-PEO) micelles in water [96, 97] PB-PEO micelles in water [85] or PEP-PEO micelles in water [44] or in water/ DMF mixture [98]. 

The influence of micellar morphology on the exchange kinetics in diblock copolymer micelles has been investigated by Lund et al. [104]. The studied system was a short chain PEPl-PEOl copolymer with symmetric block composition in water/ DMF mixtures as selective solvents for PEO. The morphological behavior of this system has already been described. The main features are illustrated in Eig. 20d. 

Structures of Poly(dimethylsiloxane)-Poly(oxyethylene) Diblock Copolymer Micelles in Aqueous Solvents... 

I 70 Structures of Po y(dimethylsiloxane)-Potf(ojc/ethYlene) Diblock Copolymer Micelles... 

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