NIST logo

Publication Citation: Self-Assembly in a Polymer Matrix and its Impact on Phase Separation

NIST Authors in Bold

Author(s): Jack F. Douglas; Jacek Dudowicz; Karl Freed;
Title: Self-Assembly in a Polymer Matrix and its Impact on Phase Separation
Published: November 11, 2008
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
Citation: Journal of Physical Chemistry
Volume: 112
Pages: pp. 16193 - 16204
Keywords: self-assembly in polymer matrix, phase separation, nanoparticles, closed loop phasew boundaries
Research Areas: Materials Science
PDF version: PDF Document Click here to retrieve PDF version of paper (272KB)