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“Pore-Like” Effects of Super-Molecular Self-Assembly on Molecular Diffusion of Poly(Ethylene Oxide)-Poly(Propylene Oxide)-Poly(Ethylene Oxide) in Water
Molecular diffusion of triblock copolymers poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) in water was studied with the help of Pulsed Field Gradient NMR in the broad range of polymer weight fractions from 0.09 to 0.8. Owing to amphiphilic nature of the molecules, these block copoly...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
MDPI
2012
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5458975/ https://www.ncbi.nlm.nih.gov/pubmed/28817019 http://dx.doi.org/10.3390/ma5050966 |
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author | Ulrich, Konstantin Galvosas, Petrik Kärger, Jörg Grinberg, Farida |
author_facet | Ulrich, Konstantin Galvosas, Petrik Kärger, Jörg Grinberg, Farida |
author_sort | Ulrich, Konstantin |
collection | PubMed |
description | Molecular diffusion of triblock copolymers poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) in water was studied with the help of Pulsed Field Gradient NMR in the broad range of polymer weight fractions from 0.09 to 0.8. Owing to amphiphilic nature of the molecules, these block copolymers exhibit rich self-organization properties when mixed with water. In particular, at ambient temperatures they form micelles and three liquid crystalline mesophases: cubic, hexagonal, and lamellar. The corresponding super-molecular structure formations were studied with the same block copolymer and at the same temperature. Self-assembly of molecules was shown to produce “pore-like” effects on their self-diffusion properties by imposing severe constraints on the dimensionality of propagation. Diffusion in the hexagonal phase was shown to be quasi one-dimensional in the direction parallel to the long axis of the ordered molecular rods. In the lamellar phase, diffusion was found to be quasi two-dimensional, in the plane of the lamellar structures. The observed diffusion anisotropy was attributed to the effects of the specific molecular ordering on the mesoscopic length scale. |
format | Online Article Text |
id | pubmed-5458975 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2012 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
spelling | pubmed-54589752017-07-28 “Pore-Like” Effects of Super-Molecular Self-Assembly on Molecular Diffusion of Poly(Ethylene Oxide)-Poly(Propylene Oxide)-Poly(Ethylene Oxide) in Water Ulrich, Konstantin Galvosas, Petrik Kärger, Jörg Grinberg, Farida Materials (Basel) Article Molecular diffusion of triblock copolymers poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) in water was studied with the help of Pulsed Field Gradient NMR in the broad range of polymer weight fractions from 0.09 to 0.8. Owing to amphiphilic nature of the molecules, these block copolymers exhibit rich self-organization properties when mixed with water. In particular, at ambient temperatures they form micelles and three liquid crystalline mesophases: cubic, hexagonal, and lamellar. The corresponding super-molecular structure formations were studied with the same block copolymer and at the same temperature. Self-assembly of molecules was shown to produce “pore-like” effects on their self-diffusion properties by imposing severe constraints on the dimensionality of propagation. Diffusion in the hexagonal phase was shown to be quasi one-dimensional in the direction parallel to the long axis of the ordered molecular rods. In the lamellar phase, diffusion was found to be quasi two-dimensional, in the plane of the lamellar structures. The observed diffusion anisotropy was attributed to the effects of the specific molecular ordering on the mesoscopic length scale. MDPI 2012-05-24 /pmc/articles/PMC5458975/ /pubmed/28817019 http://dx.doi.org/10.3390/ma5050966 Text en © 2012 by the authors; licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/3.0/). |
spellingShingle | Article Ulrich, Konstantin Galvosas, Petrik Kärger, Jörg Grinberg, Farida “Pore-Like” Effects of Super-Molecular Self-Assembly on Molecular Diffusion of Poly(Ethylene Oxide)-Poly(Propylene Oxide)-Poly(Ethylene Oxide) in Water |
title | “Pore-Like” Effects of Super-Molecular Self-Assembly on Molecular Diffusion of Poly(Ethylene Oxide)-Poly(Propylene Oxide)-Poly(Ethylene Oxide) in Water |
title_full | “Pore-Like” Effects of Super-Molecular Self-Assembly on Molecular Diffusion of Poly(Ethylene Oxide)-Poly(Propylene Oxide)-Poly(Ethylene Oxide) in Water |
title_fullStr | “Pore-Like” Effects of Super-Molecular Self-Assembly on Molecular Diffusion of Poly(Ethylene Oxide)-Poly(Propylene Oxide)-Poly(Ethylene Oxide) in Water |
title_full_unstemmed | “Pore-Like” Effects of Super-Molecular Self-Assembly on Molecular Diffusion of Poly(Ethylene Oxide)-Poly(Propylene Oxide)-Poly(Ethylene Oxide) in Water |
title_short | “Pore-Like” Effects of Super-Molecular Self-Assembly on Molecular Diffusion of Poly(Ethylene Oxide)-Poly(Propylene Oxide)-Poly(Ethylene Oxide) in Water |
title_sort | “pore-like” effects of super-molecular self-assembly on molecular diffusion of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) in water |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5458975/ https://www.ncbi.nlm.nih.gov/pubmed/28817019 http://dx.doi.org/10.3390/ma5050966 |
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