Orientational flipping and flow alignment of a model main-chain thermotropic LCP Academic Article

abstract

• A model thermotropic liquid crystalline polymer with low isotropization point, good optical transparency and thermal stability was synthesized and the evolution of orientation during flow was monitored using in situ wide angle X-ray diffraction. The polymer, a random copolyether of dihydroxymethylstilbene coupled with 7- and 9-methylene, showed a rich relationship between mesophase behavior, shear induced orientation and bulk flow properties. In the nematic phase, as DHMS-7,9 is flow-aligning, steady shear aligns its director to a fixed angle, giving rise to a nearly constant orientation parameter at different shear rates. In the x-phase, the polymer showed an interesting orientation flipping from parallel to perpendicular at low shear rates.

authors

• Ugaz, Victor

published proceedings

• American Chemical Society, Polymer Preprints, Division of Polymer Chemistry

author list (cited authors)

• Zhoit, W., Komfield, J. A., Ugaz, V. M., & Burghardt, W. R.

complete list of authors

• Zhoit, W||Komfield, JA||Ugaz, VM||Burghardt, WR

publication date

• August 1999

published in

• Papers presented at the ... meeting. American Chemical Society. Division of Polymer Chemistry  Journal

start page

• 500

end page

• 501

volume

• 40

issue

• 2