Polymer binding to carbon nanotubes in aqueous dispersions: residence time on the nanotube surface as obtained by NMR diffusometry

Anton E Frise; Guilhem Pagès; Michael Shtein; Ilan Pri Bar; Oren Regev; István Furó

doi:10.1021/jp209800u

Polymer binding to carbon nanotubes in aqueous dispersions: residence time on the nanotube surface as obtained by NMR diffusometry

J Phys Chem B. 2012 Mar 8;116(9):2635-42. doi: 10.1021/jp209800u. Epub 2012 Feb 27.

Authors

Anton E Frise¹, Guilhem Pagès, Michael Shtein, Ilan Pri Bar, Oren Regev, István Furó

Affiliation

¹ Division of Applied Physical Chemistry and Industrial NMR Centre, Department of Chemistry, Teknikringen 30-36, KTH Royal Institute of Technology, SE-10044 Stockholm, Sweden.

PMID: 22292742
DOI: 10.1021/jp209800u

Abstract

The binding of block copolymer Pluronic F-127 in aqueous dispersions of single- (SWCNT) and multiwalled (MWCNT) carbon nanotubes has been studied by pulsed-field-gradient (PFG) (1)H NMR spectroscopy. We show that a major fraction of polymers exist as a free species while a minor fraction is bound to the carbon nanotubes (CNT). The polymers exchange between these two states with residence times on the nanotube surface of 24 ± 5 ms for SWCNT and of 54 ± 11 ms for MWCNT. The CNT concentration in the solution was determined by improved thermal gravimetric analysis (TGA) indicating that the concentration of SWCNT dispersed by F-127 was significantly higher than that for MWCNT. For SWCNT, the area per adsorbed Pluronic F-127 molecule is estimated to be about 40 nm(2).

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Magnetic Resonance Spectroscopy / methods*
Nanotubes, Carbon*
Polymers / chemistry*
Surface Properties
Water

Substances

Nanotubes, Carbon
Polymers
Water