Unusual phase behavior in mixtures of poly(ethylene oxide) and ethyl alcohol
- 20 December 2005
- journal article
- research article
- Published by Wiley in Journal of Polymer Science Part B: Polymer Physics
- Vol. 44 (3), 557-564
- https://doi.org/10.1002/polb.20726
Abstract
Poly(ethylene oxide) (PEO), soluble in both aqueous and organic solvents, is one of the most intriguing polymers. PEO solution properties have been extensively studied for decades; however, many of the studies have focused on specific properties, such as clustering, of PEO in aqueous solutions, and the behavior of PEO in organic solvents has not been adequately explored. The results presented here demonstrate that PEO crystallizes into a lamellar structure in ethyl alcohol after the mixture is quenched to room temperature from a temperature above the crystal melting point. Above the melting temperature, PEO completely dissolves in ethyl alcohol, and the mixture exhibits regular polymer solution thermodynamic behavior with an upper critical solution temperature (UCST) phase diagram. Remarkably, the UCST phase boundary is significantly below the melting temperature, and this indicates that the system undergoes a crystallization process before the phase separation can occur upon cooling and, therefore, possesses an unusual phase transition. The phase transition from the crystalline state to the miscible solution state is reversible upon heating or cooling and can be induced by the addition of a small amount of water. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 557–564, 2006Keywords
This publication has 22 references indexed in Scilit:
- Clustering of poly(ethylene oxide) in water revisitedJournal of Polymer Science Part B: Polymer Physics, 2002
- SANS from Poly(ethylene oxide)/Water SystemsMacromolecules, 2002
- Monte Carlo Simulation Study of Short Poly(ethylene oxide) Chains at Different ConcentrationsThe Journal of Physical Chemistry B, 1997
- Static light scattering from poly(ethylene oxide) in methanolJournal of Polymer Science Part B: Polymer Physics, 1996
- Aggregative Behavior of Poly(ethylene oxide) in Water and MethanolMacromolecules, 1994
- Pressure-induced crossover from good to poor solvent behavior for polyethylene oxide in waterPhysical Review Letters, 1992
- Polyethylene oxide does not necessarily aggregate in waterNature, 1990
- Static and dynamic properties of poly(ethylene oxide) in methanolMacromolecules, 1990
- Role of molecular aggregates in liquid drag reduction by polymersNature, 1974
- Thermodynamics of mixtures of poly (ethylene oxide) and benzenePolymer, 1971