Intrinsic response of polymer liquid crystals in photochemical phase transition

Journal Article · Thu Jan 24 00:00:00 EST 1991 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100155a003· OSTI ID:5776539

Ikeda, Tomiki; Sasaki, Takeo; Kim, Haengboo ^[1]

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1. Tokyo Institute of Technology, Yokohama (Japan)

Time-resolved measurements were performed on the photochemically induced isothermal phase transition of polymer liquid crystals (PLC) with mesogenic side chains of phenyl benzoate (PAPB3) and cyanobiphenyl (PACB3) under conditions wherein the photochemical reaction of the doped photoresponsive molecule (4-butyl-4-{prime}-methoxyazobenzene, BMAB) was completed within {approximately} 10 ns, and the subsequent phase transition of the matrix PLC from nematic (N) to isotropic (I) state was followed by time-resolved measurements of the birefringence of the system. Formation of a sufficient amount of the cis isomer of BMAB with a single pulse of a laser lowered the N-I phase transition temperature of the mixture, inducing the N-I phase transition of PLCs isothermally in a time range of {approximately} 200 ms. This time range is comparable to that of low molecular weight liquid crystals, indicating that suppression in mobility of mesogens in PLCs does not affect significantly the thermodynamically controlled process.

• OSTI ID: 5776539
• Journal Information: Journal of Physical Chemistry; (USA), Vol. 95:2; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
BIPHENYL
PHASE TRANSFORMATIONS
LIQUID CRYSTALS
EXPERIMENTAL DATA
ORGANIC POLYMERS
PHOTOCHEMICAL REACTIONS
TRANSITION TEMPERATURE
AROMATICS
CHEMICAL REACTIONS
CRYSTALS
DATA
FLUIDS
HYDROCARBONS
INFORMATION
LIQUIDS
NUMERICAL DATA
ORGANIC COMPOUNDS
PHYSICAL PROPERTIES
POLYMERS
THERMODYNAMIC PROPERTIES
360602* - Other Materials- Structure & Phase Studies
400500 - Photochemistry