(684a) Phase Behavior and Rheology of Biopolymers Stabilized Carbon Nanotubes | AIChE

(684a) Phase Behavior and Rheology of Biopolymers Stabilized Carbon Nanotubes

Authors 

Nepal, D. - Presenter, Auburn University


The phase behavior of carbon nanotube (CNT) dispersions is of tremendous importance for its processing into varieties of forms such as films, composites, and fibers. Ordered phases of SWNTs in an aqueous system is of great demand which offers unique platform to create novel class of biological electronics and optical devices. Here we compare the isotropic-nematic phase transition of SWNT dispersed in aqueous solution of two most prominent biopolymers DNA and protein (lysozyme). At very low concentration, SWNTs in DNA dissolve as individual tubes which behave as Brownian rods. At higher concentration, SWNTs form a nematic phase consisting of spaghetti-like self-assembled supermolecular strands. At even higher concentration, the spaghetti strands self-assemble into polydomain nematic liquid crystal. The phase behavior of lysozyme-SWNT is different from that of DNA-SWNT confirming uniqueness on interaction of each of these biopolymers with the SWNTs. Details investigation using optical microscopy, atomic force microscopy, scanning electron microscopy, rheology and Raman spectroscopy will be discussed.