title: Observation of two isotropic-nematic phase transitions near a surface.
abstract: Using specified conditions, we succeeded in observing the isotropic-nematic (Iso-N) liquid crystal phase transition at surfaces followed by that in bulk for the first time. An additional heat anomaly peak was found at a higher temperature side of a main phase transition peak using highly sensitive differential scanning calorimetry (HS-DSC). The peak is pronounced particularly in the cooling process, since the transition starts at surfaces on cooling. The temperature dependence of retardation allows us to safely conclude that the higher temperature peak that appeared in HS-DSC is attributed to the Iso-N transition at surfaces. These measurements also indicate that the surface transition is of first order. These behaviors were theoretically explained by generalized Maier-Saupe theory.
authors.affiliation: Department of Organic and Polymeric Materials, Tokyo Institute of Technology, 2-12-1-S8-42 O-okayama, Meguro-ku, Tokyo 152-8552, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Aya
authors.forename: Yuji
authors.initials: Y
authors.lastname: Sasaki
authors.forename: Fumito
authors.initials: F
authors.lastname: Araoka
authors.forename: Kenji
authors.initials: K
authors.lastname: Ema
authors.forename: Ken
authors.initials: K
authors.lastname: Ishikawa
authors.forename: Alexander V
authors.initials: AV
authors.lastname: Emelyanenko
authors.forename: Hideo
authors.initials: H
authors.lastname: Takezoe