Nematic phase formation in suspensions of carbon nanotubes
Abstract
This chapter describes the chemical composition, phase behavior and structure of recently investigated carbon nanotube (CNT) based liquid crystals. Because nanotubes are long and thin rigid cylinders, their phase behavior shares several similarities with many other systems such as rigid polymers and rod-like particle suspensions. CNT liquid crystals are achieved in highly concentrated suspensions comprised of raw or chemically functionalized particles. But extreme aspect ratio, rigidity, high sensitivity to interactions, optical properties and structural features of CNTs make their liquid crystalline phases unique in several ways. In particular, the chapter discusses the importance of the CNT waviness on the phase ordering and the role of excess surfactant or biomolecules used to stabilize the CNTs. The unique resonant Raman scattering of CNT allows original and accurate measurements of order parameters at a micron-scale. Highly oriented nematic tactoids could even be characterized by polarized Raman microscopy. From a more applied point of view, nematic ordering is shown to be a route towards the processing of new materials such as anisotropic conductive films and high strength fibers made of oriented carbon nanotubes. Examples of functional materials and nanocomposites achieved from CNT liquid crystals are given.
- Publication:
-
Liquid Crystals with Nano and Microparticles (in 2 Volumes). Edited by LAGERWALL JAN P F & SCALIA GIUSY. Published by World Scientific Publishing Co. Pte. Ltd
- Pub Date:
- 2017
- DOI:
- 10.1142/9789814619264_0023
- Bibcode:
- 2017lcnm.book..775Z