Transition Bars and Related Honeycomb and Fingerprint Textures Exhibited by 12OBAC, 16OBAC and a Binary Mixture of Them

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Sparavigna, Amelia Carolina

Transition Bars and Related Honeycomb and Fingerprint Textures Exhibited by 12OBAC, 16OBAC and a Binary Mixture of Them Journal Article

Mechanics, Materials Science & Engineering, 12 , 2017, ISSN: 2412-5954.

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Authors: Amelia Carolina Sparavigna

ABSTRACT. By means of the polarized light microscopy, at the transitions between the smectic and nematic phase and between the smectic and the isotropic phase of some liquid crystals, we can observe the rising of transition bars and the presence of undulations in them. We can also see “honeycomb” and “fingerprint” textures as the evolution of the transition bars. Here, we will show some of these textures exhibited by compounds of the 4,n-alkyloxybenzoic (nOBAC) acid series. The compounds are 12OBAC, 16OBAC and a binary mixture of them. The binary mixture originates remarkable textures, which seem those of a modern art painting.

Keywords: liquid crystals, phase transitions, Alkyloxybenzoic acids

DOI 10.2412/mmse.56.32.234

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