Shigeru Machida

Dynamics of a nematic liquid crystal on a PBLG-CRA film. Time-resolved infrared spectroscopic study

Abstract The time response of a nematic liquid crystal (LC) to an applied electric field is proposed as a new dynamic index for the interaction between LCs and LC-orienting films. For a PBLG-CRA (chemical reaction alignment) film, the unique LC response observed by time-resolved infrared spectroscopy suggested a time-dependent LC-orienting effect induced by the film. On the basis of the electric field polarity dependence of the LC dynamics, we describe a model in which the applied electric field influences the orienting effect of the film, the latter originating from the inherent dipole moment of the film.

The novel texture of a liquid crystal induced by poly-γ-benzyl-L-glutamate chemical reaction alignment (CRA) film

Poly-γ-benzyl-L-glutamate (PBLG) when treated with a silane coupling agent on a glass surface forms a molecular oriented film; a new liquid crystal texture induced by the α-helical structure of PBLG attached to the substrate surface is observed.

Dynamic Behavior of a Hydrogen-Bonded Liquid Crystal Induced by the Orienting Film with a Large Dipole Moment

Abstract Poly-(γ-benzyl-L-glutamate) molecules have been bonded covalently to a flat substrate via carbonyl end group to form an aligned dipole layer (CRA film). The authors have evaluated the electric influence of the CRA film on the dynamic change of the hydrogen-bonded liquid crystalline complex of 4-hexyloxybenzoic acid and 4-nonylpyridine (6OBA-9Py) by means of time-resolved infrared spectroscopy. Using the CRA film as an orienting film for 6OBA-9Py, the absorbance change of the complex when burst electric field was applied had many steps in response to the change of its sign. Moreover, the movement of the 6OBA-9Py complex was induced by an external electric field, not only in the direction of the complex long axis but also in that of the complex short axis. This characteristic dynamic behavior of the 6OBA-9Py complex was due to the weak hydrogen bonding.

Preparation of monolayer of poly(γ-benzyl-L-glutamate) by chemical reaction on a silicon crystal surface

Poly(γ-benzyl-L-glutamate)(PBLG) reacts with a silane coupling agent on a silicon crystal surface to form a molecular oriented film; the reaction yield was determined to be 77% by X-ray photoelectron spectroscopy and the orientation of PBLG molecules attached to the substrate was interpreted based on the attenuated total reflection spectrum.

Chemical Reaction Alignment

A concept and basic results are presented to achieve an organized molecular film for optical responses. The method has been discussed in terms of work(energy) for molecular orientation.