TiO2 nanoparticle - liquid crystal interaction with smectogenic monomers and their electropolymerised polymers

• Published in: Liquid crystals 2020-02, Vol.47 (3), p.423-432
• Main Authors: Romero-Hasler, Patricio, Martínez-Miranda, Luz. J., Meneses-Franco, Ariel, Soto-Bustamante, Eduardo A.
• Format: Article
• Language: English
• Subjects: Convergence; electropolymerisation; grazing incidence X-ray scattering; Liquid crystals; Mesophase; methacrylic LC monomers; Monomers; nanoparticle interactions; Nanoparticles; Polymers; Small angle X ray scattering; Titanium dioxide
• ISSN: 0267-8292; 1366-5855
• DOI: 10.1080/02678292.2019.1655807

We observe the changes in the interactions of the liquid crystal (E)-6-(3-hydroxy-4-(((4-octyloxy)phenyl)imino)methyl) phenoxy)hexyl methacrylate (M6R8) with nanoparticles of TiO 2 as the concentration of the nanoparticle increases from 0 wt% to 30 wt%, both as a monomer as well as when they are electropolymerised with the nanoparticles included. The system is studied using transmission X-ray scattering, grazing incidence small angle X-ray scattering (GISAXS) and in-plane direction X-ray scattering. We have found that in addition to the monomer peak, we observe two peaks: a shoulder peak that appears close to the liquid crystal peak and a smaller peak that develops with particle concentration. These two peaks can be considered a result of nanoparticle - liquid crystal interaction. We find that as a function of the concentration the smC can be disordered or ordered, while the smA phases converge to the same order of magnitude, as shown by the convergence of the correlation length ξ. The order observed in the smA phase appears to be the same no matter the concentration used. Once electropolymerised we find no convergence in the region of the smA mesophase of the monomer.