NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
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.
Self-Assembly in a Polymer Matrix and its Impact on Phase Separation
Published
Author(s)
Jack F. Douglas, Jacek Dudowicz, Karl Freed
Abstract
Molecular self-assembly often occurs in the presence of long chain polymers, and we develop a theory to describe the competition between self-assembly and phase separation that gen- erally occurs in these complex uids. The theory includes a description of the particularly interesting situation where the associating `monomeric' species forms high molecular mass polymeric structures and where the assembly process transforms the phase boundary from a form typical of a polymer solution to one that resembles a polymer blend. We consider both self-assembly upon cooling and upon heating, but the van der Waals interactions are chosen so that phase separation occurs only upon cooling in the absence of association. Systems which associate upon heating prove to be particularly rich, and closed loop and ordinary (upper solution critical) phase boundaries are found to coexist over a wide range of interac- tion parameters. Each critical temperature in the limit of a large polymerization index for the matrix polymers approaches its respective theta temperature. The calculations elucidate basic physical principles governing the phase behavior of these complex mixtures. 2
Douglas, J.
, Dudowicz, J.
and Freed, K.
(2008),
Self-Assembly in a Polymer Matrix and its Impact on Phase Separation, Journal of Physical Chemistry, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=854076
(Accessed October 16, 2025)