Azobenzene-based supramolecular polymers for processing MWCNTs

Nanoscale. 2013 Jan 21;5(2):634-45. doi: 10.1039/c2nr33358a. Epub 2012 Dec 5.

Abstract

Photothermally responsive supramolecular polymers containing azobenzene units have been synthesised and employed as dispersants for multi-walled carbon nanotubes (MWCNTs) in organic solvents. Upon triggering the trans-cis isomerisation of the supramolecular polymer intermolecular interactions between MWCNTs and the polymer are established, reversibly affecting the suspensions of the MWCNTs, either favouring it (by heating, i.e. cis→trans isomerisation) or inducing the CNTs' precipitation (upon irradiation, trans→cis isomerisation). Taking advantage of the chromophoric properties of the molecular subunits, the solubilisation/precipitation processes have been monitored by UV-Vis absorption spectroscopy. The structural properties of the resulting MWCNT-polymer hybrid materials have been thoroughly investigated via thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and atomic force microscopy (AFM) and modelled with molecular dynamics simulations.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Azo Compounds / chemistry*
  • Hot Temperature
  • Kinetics
  • Materials Testing
  • Microscopy, Atomic Force / methods
  • Microscopy, Electron, Transmission / methods
  • Models, Chemical
  • Molecular Conformation
  • Nanotubes, Carbon / chemistry*
  • Organic Chemicals / chemistry
  • Photochemistry / methods
  • Polymers / chemistry*
  • Solubility
  • Solvents / chemistry
  • Surface Properties
  • Thermogravimetry / methods
  • Ultraviolet Rays
  • X-Rays

Substances

  • Azo Compounds
  • Nanotubes, Carbon
  • Organic Chemicals
  • Polymers
  • Solvents
  • azobenzene