Contact
    Start Publications Effect of superhydrophobic nanoplatelets on the phase behaviour ...
    ←  Publication Finder
    Attension

    Effect of superhydrophobic nanoplatelets on the phase behaviour of liquid crystals

    Year: 2020

    Journal: J. Mol. Liq., Volume 298, JAN 15

    Authors: Kyrou, C.; Tsiourvas, D.; Kralj, S.; Lelidis, I

    Organizations: Hellenic Foundation for Research and Innovation (HFRI) [1318]; General Secretariat for Research and Technology (GSRT), under the HFRI PhD Fellowship [1318]; Slovenian Research Agency (ARRS)Slovenian Research Agency - Slovenia [P1-0099]

    We investigate the effect of superhydrophobic Perfluorinated Silica Nanoplatelets (PFSNP) on the Isotropic-Nematic-Smectic-A-Smectic-C phase transitions of the liquid crystalline compound 4-n-pentyloxyphenyl-4'-n-octyloxybenzoate by means of polarised optical microscopy, differential scanning calorimetry, x-ray scattering, and birefringence measurements. We measure the phase transition temperature shift, coexistence temperature span variation, and the orientational order parameter of the nanocomposites, as functions of the mass fraction of nanoplatelets. These variations are non-monotonic function of PFSNP mass fraction and they are definitely related among them with linear laws. We show that the non-monotony may be related with PFSNP dispersion quality, partial-aggregation phenomena of PFSNP, and/or to nanoplatelet organization. The isotropic-nematic transition becomes softer in presence of the nanoplatelets. Nematic and smectic-C phase temperature span is practically independent from the PFSNP volume fraction. In contrary, the smectic-A phase is further stabilized for its temperature window becomes much wider in the presence of the PFSNP. A phenomenological model accounts for the experimental observations. (C) 2019 Elsevier B.V. All rights reserved.
    View publication