Magnetic-field-induced changes of the isotropic-nematic phase transition in side-chain polymer liquid crystals

The isotropic-nematic (I-N) phase transition of side-chain polymer liquid crystals is intrinsically a weak first-order transition with a biphasic region spread over a wide temperature interval. In the presence of high magnetic fields we find the I-N transition to become a strong first order. The I-N...

Full description

Saved in:
Bibliographic Details
Published inPhysical review. E, Statistical, nonlinear, and soft matter physics Vol. 67; no. 5 Pt 1; p. 050701
Main Authors Boamfa, M I, Viertler, K, Wewerka, A, Stelzer, F, Christianen, P C M, Maan, J C
Format Journal Article
LanguageEnglish
Published United States 01.05.2003
Online AccessGet more information

Cover

More Information
Summary:The isotropic-nematic (I-N) phase transition of side-chain polymer liquid crystals is intrinsically a weak first-order transition with a biphasic region spread over a wide temperature interval. In the presence of high magnetic fields we find the I-N transition to become a strong first order. The I-N biphasic region shrinks its temperature window as larger magnetic fields are applied, until it completely disappears and the transition completes at a fixed temperature. We interpret this behavior as a consequence of the nonlinear coupling of the magnetic field to the system free energy, via the suppression of the order fluctuations in the nematic mesophase at the I-N transition crossing.
ISSN:1539-3755
DOI:10.1103/PhysRevE.67.050701