| 1. |
- Crassous, Jerome, et al.
(författare)
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Design of block copolymer micelles via crystallization
- 2015
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Ingår i: Polymer. - : Elsevier BV. - 0032-3861. ; 62, s. 1-13
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Tidskriftsartikel (refereegranskat)abstract
- This Feature Article provides an overview of the progress made over the last few years in the design of diblock copolymer micelles based on crystallization-driven self-assembly (CDSA) towards the development of novel and fascinating morphologies with crystalline-cores. Here, we describe the different approaches employed in order to engineer a large variety of semicrystalline micellar architectures. We highlight kinetic strategies that have been employed to direct morphological transitions, which can then be further tuned thus increasing the range of possible micellar structures. We then emphasize the development of complex hybrid assemblies generated by taking advantage of the self-assembly process of crystalline-corona di-BCP micelles with colloidal particles. Each section introduces and emphasizes the potential applications of this class of nanomaterials. (C) 2015 Elsevier Ltd. All rights reserved.
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| 2. |
- Crassous, Jerome, et al.
(författare)
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Giant hollow fiber formation through self-assembly of oppositely charged polyelectrolyte brushes and gold nanoparticles
- 2013
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Ingår i: Soft Matter. - : Royal Society of Chemistry (RSC). - 1744-6848 .- 1744-683X. ; 9:38, s. 9111-9118
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Tidskriftsartikel (refereegranskat)abstract
- We report on the use of binary mixtures of oppositely charged gold nanoparticles (AuNPs) and spherical polyelectrolyte brushes (SPBs), consisting of a polystyrene core onto which long polystyrene sulfonate chains are grafted, as a simple model system to investigate the influence of directional interactions on self-assembly. We demonstrate that the mixing ratio, i.e., the number of AuNPs per SPB, has a profound influence on self-assembly. In particular we report on the formation of giant hollow fibers, and present a thorough characterization of these nanostructures. We speculate that the adsorption of a few AuNPs on the SPBs appears to direct the tubular self-assembly, and discuss the analogy to the case of modified proteins such as tubulin under the action of nucleotides.
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| 3. |
- Crassous, Jerome J., et al.
(författare)
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Asymmetric self-assembly of oppositely charged composite microgels and gold nanoparticles
- 2012
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Ingår i: Soft Matter. - : Royal Society of Chemistry (RSC). - 1744-6848 .- 1744-683X. ; 8:5, s. 1648-1656
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Tidskriftsartikel (refereegranskat)abstract
- The electrostatically driven self-assembly of oppositely charged gold nanoparticles (Au NPs) and polystyrene/poly(N-isopropylacrylamide) (PS/PNIPAm) core-shell microgels (CSMs) has been investigated. The co-assembly was accomplished by addition of smaller Au NPs to CSMs in dilute conditions up to a number ratio of about 1 : 1, when the suspension is destabilized. A combination of different techniques (i.e. turbidimetric titration, electrophoretic mobility, UV-visible spectroscopy, dynamic light scattering and microscopy techniques) were used to investigate the association between the two particles and the stability of the different mixtures. Hereby we demonstrate that the size ratio between the two particles (about 4 to 1) and the asymmetric character of the association result in the formation of electrostatic hybrid complexes, analogous to dipolar colloidal molecules, which further rearrange into finite sized clusters for number ratios N(AuNPs)/N(CSMs) < 1.
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| 4. |
- Zaccone, Alessio, et al.
(författare)
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Colloidal gelation with variable attraction energy
- 2013
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Ingår i: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 138:10
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Tidskriftsartikel (refereegranskat)abstract
- We present an approximation scheme to the master kinetic equations for aggregation and gelation with thermal breakup in colloidal systems with variable attraction energy. With the cluster fractal dimension d(f) as the only phenomenological parameter, rich physical behavior is predicted. The viscosity, the gelation time, and the cluster size are predicted in closed form analytically as a function of time, initial volume fraction, and attraction energy by combining the reversible clustering kinetics with an approximate hydrodynamic model. The fractal dimension d(f) modulates the time evolution of cluster size, lag time and gelation time, and of the viscosity. The gelation transition is strongly nonequilibrium and time-dependent in the unstable region of the state diagram of colloids where the association rate is larger than the dissociation rate. Only upon approaching conditions where the initial association and the dissociation rates are comparable for all species (which is a condition for the detailed balance to be satisfied) aggregation can occur with d(f) = 3. In this limit, homogeneous nucleation followed by Lifshitz-Slyozov coarsening is recovered. In this limited region of the state diagram the macroscopic gelation process is likely to be driven by large spontaneous fluctuations associated with spinodal decomposition. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4794695]
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