Flow-induced structures observed in a viscoelastic reverse wormlike micellar system by magnetic resonance imaging and NMR velocimetry

Research output: Contribution to journalArticle

Abstract

The aim of the present work is to illustrate and discuss an application of rheo-NMR techniques in the investigation of the flow micro-morphology of a rheo-thinning fluid. The viscoelastic material is composed by weakly hydrated nonionic Wormlike Micelles (WM), stabilized by the biocompatible phospholipid in an organic solvent (lecithin organogel). By applying rheo-NMR techniques, such as micro-imaging and flow velocimetry in Couette flow, to lecithin organogels in the concentrated isotropic phase, a new phase nucleating inhomogeneously at the inner rotating cylinder showing periodic fluctuations in space in some cases, has been identified for applied shear rates within the isotropic-nematic stress plateau. On the other hand, evident slippage phenomena have been found in flow regimes consistent with a full shear-induced nematic state. Bulk rheometric investigations executed in oscillatory, steady state and transient mode have been finally carried out to bridge different flow micro-heterogeneities detected by rheo-NMR with a variety of mechanical responses manifested by lecithin WM.

Details

Authors
  • R. Angelico
  • L. Gentile
  • G. A. Ranieri
  • C. Oliviero Rossi
Organisations
External organisations
  • University of Calabria
  • University of Molise
  • Research Center for Colloids and Nanoscience
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Physical Chemistry
Original languageEnglish
Pages (from-to)33339-33347
Number of pages9
JournalRSC Advances
Volume6
Issue number40
Publication statusPublished - 2016 Mar 30
Publication categoryResearch
Peer-reviewedYes