Polydomain growth at isotropic-nematic transitions in liquid crystalline polymers

Shunsuke Yabunaka, Takeaki Araki

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

We studied the dynamics of isotropic-nematic transitions in liquid crystalline polymers by integrating time-dependent Ginzburg-Landau equations. In a concentrated solution of rodlike polymers, the rotational diffusion constant Dr of the polymer is severely suppressed by the geometrical constraints of the surrounding polymers so that the rodlike molecules diffuse only along their rod directions. In the early stage of phase transition, the rodlike polymers with nearly parallel orientations assemble to form a nematic polydomain. This polydomain pattern, with characteristic length ?, grows with self-similarity in three dimensions over time with an ?~t1/4 scaling law. In the late stage, the rotational diffusion becomes significant, leading to a crossover of the growth exponent from 1/4 to 1/2. This crossover time is estimated to be on the order of t~Dr-1. We also examined the time evolution of a pair of disclinations placed in a confined system by solving the same time-dependent Ginzburg-Landau equations in two dimensions. If the initial distance between the disclinations is shorter than some critical length, they approach and annihilate each other; however, at larger initial separations, they are stabilized.

Original languageEnglish
Article number061711
JournalPhysical Review E - Statistical, Nonlinear, and Soft Matter Physics
Volume83
Issue number6
DOIs
Publication statusPublished - Jun 28 2011

Fingerprint

Liquid Crystalline Polymer
Polymers
Ginzburg-Landau Equation
polymers
liquids
Landau-Ginzburg equations
Crossover
crossovers
Self-similarity
Scaling Laws
Three-dimension
Two Dimensions
Phase Transition
scaling laws
Exponent
Molecules
rods
exponents
molecules

All Science Journal Classification (ASJC) codes

  • Statistical and Nonlinear Physics
  • Statistics and Probability
  • Condensed Matter Physics

Cite this

Polydomain growth at isotropic-nematic transitions in liquid crystalline polymers. / Yabunaka, Shunsuke; Araki, Takeaki.

In: Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, Vol. 83, No. 6, 061711, 28.06.2011.

Research output: Contribution to journalArticle

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