Uniaxial alignment of nematic liquid crystals filling vacant spaces in surface-treated nanofibre nonwoven

ABSTRACT

Nematic liquid crystals (NLCs) absorbed in a nonwoven of surface-treated silica nanofibres (SiO₂-NFs) orient the director along the nonwoven thickness direction if the NLCs prefer homeotropic anchoring onto the fibre surface. The nonwoven has vacant spaces with the dimensions of 0.3 and 0.6 μm in the thickness and cross directions, respectively, bordered with SiO₂-NFs with 93 nm in diameter. The SiO₂-NF surface was treated with a silane-coupling agent to induce the homeotropic anchoring of NLC mesogens onto the surface. The nematic director is arranged radially from the fibres although it is more severely constrained by the proximity between fibre surfaces along the thickness direction. Consequently, the NLCs can align along the nonwoven thickness direction involving −1/2 wedge disclinations on both sides of the fibres.

Graphical Abstract

KEYWORDS:

• Nematic
• nanofibre
• nonwoven
• homeotropic orientation
• anchoring

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary materials

Supplemental materials for this article can be accessed here.

Additional information

Funding

This study was partially supported by the Strategic Promotion of Innovative Research and Development from the Japan Science and Technology Agency, JST.