Thermal aggregation properties of nanoparticles modified with temperature sensitive copolymers

Kristen L. Hamner, Mathew M. Maye

Research output: Contribution to journalArticlepeer-review

37 Scopus citations

Abstract

In this paper, we describe the use of a temperature responsive polymer to reversibly assemble gold nanoparticles of various sizes. Temperature responsive, low critical solution temperature (LCST) pNIPAAm-co-pAAm polymers, with transition temperatures (TC) of 51 and 65 C, were synthesized with a thiol modification, and grafted to the surface of 11 and 51 nm gold nanoparticles (AuNPs). The thermal-responsive behavior of the polymer allowed for the reversible aggregation of the nanoparticles, where at T < T C the polymers were hydrophilic and extended between particles. In contrast, at T > TC, the polymer shell undergoes a hydrophilic to hydrophobic phase transition and collapses, decreasing interparticle distances between particles, allowing aggregation to occur. The AuNP morphology and polymer conjugation were probed by TEM, FTIR, and 1H NMR. The thermal response was probed by UV-vis and DLS. The structure of the assembled aggregates at T > TC was studied via in situ small-angle X-ray scattering, which revealed interparticle distances defined by polymer conformation.

Original languageEnglish (US)
Pages (from-to)15217-15223
Number of pages7
JournalLangmuir
Volume29
Issue number49
DOIs
StatePublished - Dec 10 2013

ASJC Scopus subject areas

  • General Materials Science
  • Condensed Matter Physics
  • Surfaces and Interfaces
  • Spectroscopy
  • Electrochemistry

Fingerprint

Dive into the research topics of 'Thermal aggregation properties of nanoparticles modified with temperature sensitive copolymers'. Together they form a unique fingerprint.

Cite this