Dispersing\nCarbon Nanotubes by Chiral Network Surfactants

Abstract

Chiral\nnetwork surfactants (CNSs) possessing miscibility with carbon\nnanotubes (CNTs) and chiral materials are applied to disperse CNTs.\nUltraviolet–visible absorption spectroscopy is used to quantitatively\ndetermine the CNT concentration in homogeneous CNT–CNS dispersions,\nresults indicate that CNSs with more mole fraction of polycyclic conjugated\nstructure have better ability to load and disperse CNTs and the maximal\nconcentration reaches 0.79 mg mL^–1. Fourier transform\ninfrared imaging system is utilized to analyze the dispersibility\nof CNTs in CNT–CNS composites, and CNS with 6 mol % nonmesogens\n(S6) induces the best dispersibility. The CNT doped CNSs exhibit lower\nglass transition temperature, strengthened thermal stability, decreased\nthe thermochromic temperature and enriched reflected colors of CNSs.\nFurthermore, S6 are used as a promoter to disperse CNTs in chiral\nhost, here, a left-handed chiral liquid crystal (CLC) is selected,\nthe miscibility between CNTs and CLCs is studied by polarized optical\nmicroscope, and CNTs can be effectively dispersed in CLCs by S6. The\nCNT dispersed CLCs can exhibit a faster electro-optical response process\nthan neat CLCs.