Skip to main content
U.S. flag

An official website of the United States government

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.

Structure and Dynamics of Interacting Nanoparticles in Semidilute Polymer Solutions



Ryan Poling-Skutvik, Katrina Irene S. Mongcopa, Antonio Faraone, Suresh Narayanan, Jacinta C. Conrad, Ramanan Krishnamoorti


We investigate the structure and dynamics of silica nanoparticles and polymer chains in semidilute solutions of high molecular weight polystyrene in 2-butanone to determine the effect of long range interparticle interactions on the coupling between particle and polymer dynamics. Particles at weight concentrations of 1 to 10% are well dispersed in the semidilute polymer solutions and exhibit long range electrostatic repulsions between particles. Because the particles are comparably sized to the radius of gyration of the polymer, the particle dynamics are predicted to couple to those of the polymer. We verify that the polymer structure and dynamics are not significantly affected by the particles, indicating that the particle-polymer coupling does not change with increasing particle loading. We find that the coupling between the dynamics of comparably sized particles and polymer results in subdiffusive particle dynamics, as expected. Over the interparticle distance, however, the particle dynamics are hindered and not fully described by the relaxation of the surrounding polymer chains. Instead, the particle dynamics are inversely related to the structure factor, suggesting that both long range interactions between particles and physical particle-polymer coupling present energetic barriers to particle motion that lead to de Gennes narrowing and subdiffusive dynamics.


Poling-Skutvik, R. , Mongcopa, K. , Faraone, A. , Narayanan, S. , Conrad, J. and Krishnamoorti, R. (2016), Structure and Dynamics of Interacting Nanoparticles in Semidilute Polymer Solutions, Macromolecules, [online], (Accessed July 13, 2024)


If you have any questions about this publication or are having problems accessing it, please contact

Created August 16, 2016, Updated October 12, 2021