Nematic director reorientation at solid and liquid interfaces under flow: SAXS studies in a microfluidic device.

ABSTRACT: In this work we investigate the interplay between flow and boundary condition effects on the orientation field of a thermotropic nematic liquid crystal under flow and confinement in a microfluidic device. Two types of experiments were performed using synchrotron small-angle X-ray-scattering (SAXS). In the first, a nematic liquid crystal flows through a square-channel cross section at varying flow rates, while the nematic director orientation projected onto the velocity/velocity gradient plane is measured using a 2D detector. At moderate-to-high flow rates, the nematic director is predominantly aligned in the flow direction, but with a small tilt angle of ∼±11° in the velocity gradient direction. The director tilt angle is constant throughout most of the channel width but switches sign when

SUBMITTER: Silva BF 

PROVIDER: S-EPMC4400036 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature