The effect of preparation conditions and biopolymer dispersants on the properties of SWNT buckypapers

The effect of varying preparation conditions on the properties of buckypapers made using single-walled carbon nanotubes (SWNTs) was systematically investigated. Changing the sonication time, final dispersion volume or membrane filter used to prepare SWNT–Triton X-100 buckypapers all generally had only a small influence on the density, thickness, contact angle and electrical conductivity of the resulting material. More significant changes were noted when the effects of variations in the above preparation conditions on the mechanical properties and surface morphology of SWNT–Triton X-100 buckypapers were investigated. However, the largest changes in properties were found when various biopolymers (bovine serum albumin, lysozyme, gellan gum and chitosan) were used instead of Triton X-100 to prepare dispersions from which the buckypapers were made. It was observed that the electrical conductivity of the buckypapers decreased as the molecular mass of the biopolymer dispersant used increased, whereas the mechanical properties of the materials showed significant improvements.