Rheologica Acta

, Volume 32, Issue 3, pp 245–253 | Cite as

The rheology of layered liquids: lamellar block copolymers and smectic liquid crystals

  • R. G. Larson
  • K. I. Winey
  • S. S. Patel
  • H. Watanabe
  • R. Bruinsma
Original Contributions

Abstract

The frequency-dependence of the viscoelastic shear modulus at low frequencies in a lamellar polystyrene-polyisoprene block copolymer is qualitatively identical to that measured in small-molecule smectics, namely, the rod-like 4-cyano-4′-octylbiphenyl and the flexible n-nonyl-1-O-β-D-glucopyranoside. All three materials were studied after quenching from the isotropic state, and during and after alignment by large-amplitude oscillatory shearing. The kinetics of aligning, as measured by changes in moduli during shearing, are similar, despite great differences in molecular characteristics. These moduli and the aligning process are evidently controlled by smectic fluctuations and defects, the dynamics of which have universal features.

Key words

Block copolymers smectics liquid crystals lamellar structure 

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Copyright information

© Steinkopff-Verlag 1993

Authors and Affiliations

  • R. G. Larson
    • 1
  • K. I. Winey
    • 1
  • S. S. Patel
    • 1
  • H. Watanabe
    • 2
  • R. Bruinsma
    • 3
  1. 1.AT&T Bell LaboratoriesMurray Hill
  2. 2.Department of Macromolecular ScienceOsaka UniversityToyonaka, OsakaJapan
  3. 3.Department of PhysicsUniversity of CaliforniaLos Angeles

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