skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Nanostructure in block copolymer solutions: Rheology and small-angle neutron scattering

Abstract

Triblock copolymers composed of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) present an amphiphilic character in aqueous solutions. Since PPO is less hydrophilic than PEO and since their solubilities decrease when the temperature increases, the copolymers self-assemble spontaneously, forming micelles at moderate temperatures. For higher temperatures or concentrations, the copolymers or the micelles are ordered because of repulsive interactions and form lyotropic liquid crystalline phases. These are phases of very great viscosity with the aspect of gels, and transitions between different crystalline phases can occur at fixed concentration during an increase of temperature. We studied solutions of three different copolymers. The first two have a star structure. They are both composed of four branches (EO){sub x}(PO){sub y} fixed on an ethylene diamine, but differ by the values of x and y. Their commercial name is Tetronic 908 (x=114, y=21) and Tetronic 704 (x=16, y=18). The third copolymer (EO){sub 37}(PO){sub 56}(EO){sub 37} is linear and is known under the name of Pluronic P105. The measurements of the shear complex elastic modulus according to the temperature is used to determine the temperatures of the different transitions. Then, small-angle neutron scattering on samples under flow and true crystallographic arguments make it possible tomore » identify the nature of the crystalline phases. For the systems studied, we show that the branched copolymers form only one type of liquid crystalline phase, which is bcc for the T908 and lamellar for the T704. For the linear copolymer, it is possible to identify three transitions: micellar solution to hexagonal phase, hexagonal phase to body-centered cubic phase, and finally body-centered cubic phase to lamellar phase.« less

Authors:
; ; ; ;  [1]
  1. Laboratoire de Physico-Chimie des Polymeres UMR 5067, Universite de Pau et des Pays de l'Adour, Avenue de l'Universite, 64000 Pau (France)
Publication Date:
OSTI Identifier:
20636892
Resource Type:
Journal Article
Journal Name:
Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics
Additional Journal Information:
Journal Volume: 70; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevE.70.061802; (c) 2004 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1063-651X
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AQUEOUS SOLUTIONS; BCC LATTICES; COPOLYMERS; CRYSTALLOGRAPHY; ETHYLENE; LIQUID CRYSTALS; NANOSTRUCTURES; NEUTRON DIFFRACTION; OXIDES; PHASE TRANSFORMATIONS; PROPYLENE; RHEOLOGY; SMALL ANGLE SCATTERING; VISCOSITY

Citation Formats

Habas, Jean-Pierre, Pavie, Emmanuel, Perreur, Christelle, Lapp, Alain, Peyrelasse, Jean, Laboratoire Leon Brillouin CEA Saclay, 91191 Gif-sur-Yvette Cedex, and Laboratoire de Physico-Chimie des Polymeres UMR 5067, Universite de Pau et des Pays de l'Adour, Avenue de l'Universite, 64000 Pau. Nanostructure in block copolymer solutions: Rheology and small-angle neutron scattering. United States: N. p., 2004. Web. doi:10.1103/PhysRevE.70.061802.
Habas, Jean-Pierre, Pavie, Emmanuel, Perreur, Christelle, Lapp, Alain, Peyrelasse, Jean, Laboratoire Leon Brillouin CEA Saclay, 91191 Gif-sur-Yvette Cedex, & Laboratoire de Physico-Chimie des Polymeres UMR 5067, Universite de Pau et des Pays de l'Adour, Avenue de l'Universite, 64000 Pau. Nanostructure in block copolymer solutions: Rheology and small-angle neutron scattering. United States. https://doi.org/10.1103/PhysRevE.70.061802
Habas, Jean-Pierre, Pavie, Emmanuel, Perreur, Christelle, Lapp, Alain, Peyrelasse, Jean, Laboratoire Leon Brillouin CEA Saclay, 91191 Gif-sur-Yvette Cedex, and Laboratoire de Physico-Chimie des Polymeres UMR 5067, Universite de Pau et des Pays de l'Adour, Avenue de l'Universite, 64000 Pau. Wed . "Nanostructure in block copolymer solutions: Rheology and small-angle neutron scattering". United States. https://doi.org/10.1103/PhysRevE.70.061802.
@article{osti_20636892,
title = {Nanostructure in block copolymer solutions: Rheology and small-angle neutron scattering},
author = {Habas, Jean-Pierre and Pavie, Emmanuel and Perreur, Christelle and Lapp, Alain and Peyrelasse, Jean and Laboratoire Leon Brillouin CEA Saclay, 91191 Gif-sur-Yvette Cedex and Laboratoire de Physico-Chimie des Polymeres UMR 5067, Universite de Pau et des Pays de l'Adour, Avenue de l'Universite, 64000 Pau},
abstractNote = {Triblock copolymers composed of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) present an amphiphilic character in aqueous solutions. Since PPO is less hydrophilic than PEO and since their solubilities decrease when the temperature increases, the copolymers self-assemble spontaneously, forming micelles at moderate temperatures. For higher temperatures or concentrations, the copolymers or the micelles are ordered because of repulsive interactions and form lyotropic liquid crystalline phases. These are phases of very great viscosity with the aspect of gels, and transitions between different crystalline phases can occur at fixed concentration during an increase of temperature. We studied solutions of three different copolymers. The first two have a star structure. They are both composed of four branches (EO){sub x}(PO){sub y} fixed on an ethylene diamine, but differ by the values of x and y. Their commercial name is Tetronic 908 (x=114, y=21) and Tetronic 704 (x=16, y=18). The third copolymer (EO){sub 37}(PO){sub 56}(EO){sub 37} is linear and is known under the name of Pluronic P105. The measurements of the shear complex elastic modulus according to the temperature is used to determine the temperatures of the different transitions. Then, small-angle neutron scattering on samples under flow and true crystallographic arguments make it possible to identify the nature of the crystalline phases. For the systems studied, we show that the branched copolymers form only one type of liquid crystalline phase, which is bcc for the T908 and lamellar for the T704. For the linear copolymer, it is possible to identify three transitions: micellar solution to hexagonal phase, hexagonal phase to body-centered cubic phase, and finally body-centered cubic phase to lamellar phase.},
doi = {10.1103/PhysRevE.70.061802},
url = {https://www.osti.gov/biblio/20636892}, journal = {Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics},
issn = {1063-651X},
number = 6,
volume = 70,
place = {United States},
year = {2004},
month = {12}
}