Effects of polymer wrapping and covalent functionalization on the stability of MWCNT in aqueous dispersions

Susana Addo Ntim, Ornthida Sae-Khow, Frank A. Witzmann, Somenath Mitra

Research output: Contribution to journalArticle

79 Scopus citations


The colloidal behavior of aqueous dispersions of functionalized multiwall carbon nanotubes (F-CNTS) formed via carboxylation and polymer wrapping with polyvinyl pyrrolidone (PVP) is presented. The presence of polymer on the nanotube surface provided steric stabilization, and the aggregation behavior of the colloidal system was quite different from its covalently functionalized analog. Based on hydrophobicity index, particle size distribution, zeta potential as well as the aggregation kinetics studied using time-resolved dynamic light scattering, the PVP wrapped CNT was somewhat less prone to agglomeration. However, its long-term stability was lower, and this was attributed to the partial unwrapping of the polyvinyl pyrrolidone layer on the CNT surface.

Original languageEnglish (US)
Pages (from-to)383-388
Number of pages6
JournalJournal of Colloid and Interface Science
Issue number2
StatePublished - Mar 15 2011



  • Aggregation
  • Carbon nanotubes
  • Hydrophobicity
  • Stability

ASJC Scopus subject areas

  • Surfaces, Coatings and Films
  • Electronic, Optical and Magnetic Materials
  • Biomaterials
  • Colloid and Surface Chemistry

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