Investigation of terminal olefine in the isothiocyanatotolane liquid crystals with alkoxy end group

ABSTRACT

Three series of liquid crystals based on isothiocyanatotolane core with terminal alkenoxy groups (4A-1‒4C-2) have been synthesised via multi-step reactions. Their thermotropic mesophases and physical properties are evaluated by comparison with the alkoxyl analogues (4a-1‒4c-2). The results show that the isothiocyanatotolane LCs with alkenoxyl terminals deliver higher birefringence (0.410~0.436), lower melting points, lower melting enthalpies and viscosity. The effects of the alkenoxy terminal groups and the lateral fluoro substituents on the mesomorphic behaviour and physical properties are discussed. The formulation of the mixture containing isothiocyanatotolane liquid crystals with alkenoxyl terminals provides evidence of an useful candidate for liquid crystal photonics.

GRAPHICAL ABSTRACT

KEYWORDS:

• Isothiocyanatotolanes
• alkenoxy group
• birefringence
• melting point
• rotational viscosity

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the the Defence Industrial Technology Development Program of China [Grant Number JSHS2015208B005]; the State Key Laboratory of Applied Optics [Grant Number Y6133FQ112]; the National Natural Science Foundation of China [Grant Number 61378075].