Structure and Entanglement Factors on Dynamics of Polymer-Grafted Nanoparticles

Siqi Liu, Erkan Senses, Yang Jiao, Suresh Narayanan, Pinar Akcora

Research output: Contribution to journalArticlepeer-review

45 Scopus citations

Abstract

Nanoparticles functionalized with long polymer chains at low graft density are interesting systems to study structure-dynamic relationships in polymer nanocomposites since they are shown to aggregate into strings in both solution and melts and also into spheres and branched aggregates in the presence of free polymer chains. This work investigates structure and entanglement effects in composites of polystyrene-grafted iron oxide nanoparticles by measuring particle relaxations using X-ray photon correlation spectroscopy. Particles within highly ordered strings and aggregated systems experience a dynamically heterogeneous environment displaying hyperdiffusive relaxation commonly observed in jammed soft glassy systems. Furthermore, particle dynamics is diffusive for branched aggregated structures which could be caused by less penetration of long matrix chains into brushes. These results suggest that particle motion is dictated by the strong interactions of chains grafted at low density with the host matrix polymer.

Original languageEnglish
Pages (from-to)569-573
Number of pages5
JournalACS Macro Letters
Volume5
Issue number5
DOIs
StatePublished - 17 May 2016

Fingerprint

Dive into the research topics of 'Structure and Entanglement Factors on Dynamics of Polymer-Grafted Nanoparticles'. Together they form a unique fingerprint.

Cite this