Hammouda, B.
(2010),
The Mystery of Clustering in Macromolecular Media, Polymer, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=905298 (Accessed May 17, 2026)
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
The Mystery of Clustering in Macromolecular Media
Published
Author(s)
Abstract
Clustering prevails in water-soluble polymers and biological macromolecules. It has also been observed in polar solvent mixtures. The possible causes of clustering are discussed. A systematic investigation of clustering in poly(ethylene oxide)/d-water solutions has been undertaken using the small-angle neutron scattering (SANS) method. The PEO monomer is formed of an oxygen atom and an ethylene group. Using the Random Phase Approximation (RPA), partial Flory-Huggins interaction parameters for the three pairs (oxygen/d-water, ethylene/d-water and oxygen/ethylene) are derived. Results show that the first two (oxygen/d-water and ethylene/d-water) are characterized by a lower critical solution temperature (LCST) phase behavior (whereby phase separation occurs upon heating), while the third one (oxygen/ethylene) is characterized by an upper critical solution temperature (UCST) phase diagram (whereby phase separation occurs upon cooling). Clustering is caused by the tendency of this last pair (oxygen/ethylene) to demix while the polymer itself dissolves well.Citation
Polymer
Volume
50
Pub Type
Journals
Download Paper
Citation
Issues
If you have any questions about this publication or are having problems accessing it, please contact [email protected].
Created June 1, 2010, Updated February 19, 2017