Multicompartment micelles from ABC miktoarm stars in water.
01 Oct 2004-Science (American Association for the Advancement of Science)-Vol. 306, Iss: 5693, pp 98-101
TL;DR: By combining three mutually immiscible polymeric components in a mixed-arm star block terpolymer architecture, this work has observed the formation of a previously unknown class of multicompartment micelles in dilute aqueous solution.
Abstract: By combining three mutually immiscible polymeric components in a mixed-arm star block terpolymer architecture, we have observed the formation of a previously unknown class of multicompartment micelles in dilute aqueous solution. Connection of water-soluble poly(ethylene oxide) and two hydrophobic but immiscible components (a polymeric hydrocarbon and a perfluorinated polyether) at a common junction leads to molecular frustration when dispersed in aqueous solution. The incompatible hydrophobic blocks form cores that are protected from the water by the poly(ethylene oxide) blocks, but both are forced to make contact with the poly(ethylene oxide) by virtue of the chain architecture. The structures that emerge depend on the relative lengths of the blocks and can be tuned from discrete multicompartment micelles to extended wormlike structures with segmented cores.
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Cites background from "Multicompartment micelles from ABC ..."
...Miktoarm star copolymers have shown interesting properties, such as microphase separations in bulk [110–112], in solution [113,114], at interfaces [115], and segregated compartmentalization for guest molecule encapsulation [113]....
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References
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Journal Article•
TL;DR: Future applications of polymer vesicles will rely on exploiting unique property-performance relations, but results to date underscore the fact that biologically derived vesicle are but a small subset of what is physically and chemically possible.
Abstract: Vesicles are microscopic sacs that enclose a volume with a molecularly thin membrane. The membranes are generally self-directed assemblies of amphiphilic molecules with a dual hydrophilic-hydrophobic character. Biological amphiphiles form vesicles central to cell function and are principally lipids of molecular weight less than 1 kilodalton. Block copolymers that mimic lipid amphiphilicity can also self-assemble into vesicles in dilute solution, but polymer molecular weights can be orders of magnitude greater than those of lipids. Structural features of vesicles, as well as properties including stability, fluidity, and intermembrane dynamics, are greatly influenced by characteristics of the polymers. Future applications of polymer vesicles will rely on exploiting unique property-performance relations, but results to date already underscore the fact that biologically derived vesicles are but a small subset of what is physically and chemically possible.
2,423 citations
TL;DR: In this paper, dense periodic arrays of holes and dots have been fabricated in a silicon nitride-coated silicon wafer and transferred directly to the underlying silicon oxide layer by two complementary techniques.
Abstract: Dense periodic arrays of holes and dots have been fabricated in a silicon nitride–coated silicon wafer. The holes are 20 nanometers across, 40 nanometers apart, and hexagonally ordered with a polygrain structure that has an average grain size of 10 by 10. Spin-coated diblock copolymer thin films with well-ordered spherical or cylindrical microdomains were used as the templates. The microdomain patterns were transferred directly to the underlying silicon nitride layer by two complementary techniques that resulted in opposite tones of the patterns. This process opens a route for nanometer-scale surface patterning by means of spontaneous self-assembly in synthetic materials on length scales that are difficult to obtain by standard semiconductor lithography techniques.
1,921 citations
TL;DR: A general overview of the preparation, characterization and theories of block copolymer micellar systems is presented in this paper, with examples of micelle formation in aqueous and organic medium are given for di-and triblock copolymers, as well as for more complex architectures.
1,856 citations
Book•
01 Jan 1998
TL;DR: The self consistent field theory of block copolymers has been studied in this article, where the authors describe the behavior of blockcopolymers in a variety of ways: 1. Melt Phase Behaviour of Block Copolymers 2. Block copolymer in Dilute Solution 3. Block Copylmers in Semidilute Solution 4.
Abstract: 1. Introduction 2. Melt Phase Behaviour of Block Copolymers 3. Block Copolymers in Dilute Solution 4. Block Copolymers in Semidilute and Concentrated Solutions 5. Solid State Structure of Block Copolymers 6. Blends Containing Block Copolymers Appendix: The Self Consistent Field Theory
1,606 citations
TL;DR: In this paper, a review of the current efforts to utilize block copolymers in nanotechnologies including nanostructured membranes, BCP templates for nanoparticle synthesis, photonic crystals, and high-density information storage media is presented.
1,466 citations