Colloidal interactions in thermal and athermal polymer solutions: The Derjaguin approximation, and exact results for mono- and polydisperse ideal chains

Research output: Contribution to journalArticle


Polymer density functional theory is used to test the accuracy of the Derjaguin approximation in describing the interaction between two spherical colloidal particles immersed in a polymer solution. The density functional equations are solved numerically in a cylindrical geometry and thus a rigorous comparison is afforded, within the density functional framework. The density functional theory provides an exact (albeit numerical) treatment for ideal polymers. We investigate both nonadsorbing and telechelic chains, as well as consider the behavior of widely polydisperse samples (living chains). We make comparisons with the commonly used penetrable sphere models for polymers and are able to identify strengths and weaknesses in the latter. We find that the Derjaguin approximation performs surprisingly well, even for particle sizes that are comparable to the radius of gyration of the polymers.


Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Theoretical Chemistry


  • density functional theory, colloids, liquid theory, liquid structure, polymer solutions
Original languageEnglish
Article number044903
JournalJournal of Chemical Physics
Issue number4
Publication statusPublished - 2009
Publication categoryResearch

Bibliographic note

The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Theoretical Chemistry (S) (011001039)