Papers by Keyword: Bent-Core Liquid Crystal

Abstract: A bent-core liquid crystal compound N,N-bis (4-propoxybenzylidene)benzene- 1,3-diamine was synthesized. Phase transition properties of the synthesized compound with the deferent heating rate were characterized with differential scanning calorimetry and polarized optical microscopy. , respectively. Our results demonstrated that the bent-core compound exhibited the completely undivided multi-phases in heating-rate ranges from 1oC/min to 6oC/min while it showed a broad-peak crystal phase in higher heating-rate ranges of 7-10oC/min for the first heating.

Abstract: With the ultraviolet-visible spectrophotometry, we have investigated the effects of red laser (633 nm) and green laser (532 nm) irradiations on the optical absorption of the ethyl alcohol solutions of an azo-containing bent-core liquid crystal. As the irradiation duration increases, the optical absorptions at about 360 nm of the bent-core compound exhibit concentration dependent and irradiation-time dependent features. The absorptions of dilute solutions (~2.2 mg/litter) are not sensitive to the laser irradiation duration whereas the absorptions of higher concentrations (~10 mg/litter) decrease as the laser irradiation continues. Our results have demonstrated that laser irradiation induced thermolysis is responsible for the dissociation of the azo-linkages in azo-containing bent-core compound. The mechanisms on the red and green light irradiations are discussed.

Abstract: We demonstrate that a bent-core liquid crystal 1,3-phenylene-bis(4-butoxybenzylidene amine) can write the Chinese character 人, which means a person in English, when the bent-core compound gets cooled from its isotropic phase. The polarized optical microscopic graphs illustrate that the bent-core molecules are able to self-assemble themselves into the Chinese character either in a sequential order or in a reverse order. Our results reveal that bent-core molecules have the capability of being smart materials.

Abstract: A three-ring containing bent-core compound 1,3-phenylene-bis(4-butoxybenzylidene amine) was synthesized and characterized with differential scanning calorimetry and polarized optical microscopy. It exhibited mesophases in the temperature range of 48-54oC for the first cyclic heating and cooling. Our results demonstrated that three-ring containing bent-core molecules can form mesophases.

Abstract: A bent-core compound with three benzene-ring cores 1,3-phenylene-bis [4-(nonylcarboyloxyl)benzyl ideneamine] was synthesized. Its mesomorphic properties were characterized with differential scanning calorimetry and polarized optical microscopy, respectively. This kind of bent-core compound exhibited mesophases in the temperature range of 155-185oC for the first cooling but cyclic heating and cooling could lower the phase transition temperatures for this bent-core liquid crystal. Our results demonstrated that bent-core molecules with three benzene-ring cores can also form mesophases as those five benzene-ring containing bent-core molecules do.