Synthesis and characterisation of two homologous series of LC acrylic monomers based on phenolic and resorcinic azobenzene groups

ABSTRACT

The synthesis and phase characterisation of two homologous series of monomers of acrylic azo-compounds has been presented. The characterisation comprises polarising optical microscopy (POM), differential scanning calorimetry (DSC) and powder X-ray diffractometry (PXRD). All studied monomers exhibit a narrow nematic phase with decrease in temperature range while increasing the alkoxy tail length. For the resorcinic azo benzenes at higher tail lengths, SmA and SmC phases are present. Phenolic azo compounds show only SmA phase. The resorcinic family showed more stable phases, with broader liquid crystalline temperature range than its phenolic equivalent.

GRAPHICAL ABSTRACT

KEYWORDS:

• Acrylic monomers
• liquid crystals (LCs)
• X-ray diffraction (XRD)
• polarised microscopy
• calorimetry

Acknowledgements

P. Romero-Hasler acknowledges CONICYT scholarship 21130413 for doctoral studies and E. A. Soto-Bustamante thanks FONDECYT Project 1130187.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Comisión Nacional de Investigación Científica y Tecnológica [21130413] and the Fondo Nacional de Desarrollo Científico y Tecnológico [1130187].