Nonlinear behavior of nematic platelet dispersions in shear flow

M. P. Lettinga, P. Holmqvist, P. Ballesta, S. Rogers, D. Kleshchanok, B. Struth

Research output: Contribution to journalArticlepeer-review

Abstract

Dispersions of platelets in the nematic phase are submitted to large amplitude oscillatory shear flow and probed by high temporal resolution small angle x-ray scattering. The response displays rich dynamic and structural behavior. Under small amplitude deformations we observe an elastic response, while structurally symmetry is broken: a preferential direction of deformation is selected which induces off-plane orientation of the platelets. We associate the elastic responses with the tilting director of the platelets towards the flow direction at all strain amplitudes. At large strain amplitudes there is a yielding transition between elastic and plastic deformation, accompanied by a flipping of the director. At intermediate strain amplitudes the director has a rich dynamic behavior, illustrating the complex motion of platelets in shear flow. These observations are confirmed by steady-shear flow reversal experiments, which underline the unique character of sheared nematic platelet dispersions.

Original languageEnglish (US)
Article number246001
JournalPhysical review letters
Volume109
Issue number24
DOIs
StatePublished - Dec 12 2012
Externally publishedYes

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Fingerprint

Dive into the research topics of 'Nonlinear behavior of nematic platelet dispersions in shear flow'. Together they form a unique fingerprint.

Cite this