Non-covalent functionalization of pristine few-layer graphene using triphenylene derivatives for conductive poly (vinyl alcohol) composites

Effect of dsDNA wrapped single-walled carbon nanotubes on the thermal and mechanical properties of polycaprolactone and polyglycolide fiber blend composites

“…The fibers also do not display any SWNT aggregates, further indicating that the dsDNA wrapping procedure assisted with dispersing the SWNTs within the biopolymer blend. Prior studies have shown that freeze drying of CNTs to remove water after wrapping procedures does not affect their ability to be redispersed in water and other solvents [4,17,32]. This research concurs with those studies and further shows that freeze drying had no effect on the dsDNA-SWNTs ability to be re-dispersed into the HFP solvent for electrospinning of the biopolymer blend.…”

Liquid phase exfoliation and crumpling of inorganic nanosheets

“…Dynamic light scattering (DLS) was also utilized to measure the size (hydrodynamic radius) distribution of BNNSs ( Fig. 52,53 Some of these features (e.g., shape) are reflective of differences in parent material morphology; however, the straight edges and folds may indicate differences in bending moduli and sonication response. From the DLS data, the number-average hydrodynamic radius for the dispersed BNNSs is 204 nm and the maximum value is 900 nm; these values compare quite well against the TEM images in Fig.…”

Adsorption and removal of graphene dispersants

“…This method allows for the production of pristine graphene-based nanocomposites [1,[7][8][9][10], gels [11,12], and films [13][14][15]. Despite the frequent use of graphene dispersants, the kinetics of dispersant adsorption, desorption, and removal are poorly understood and often neglected in the literature.…”

“…These results suggest that removal of dispersants from the dispersion itself (either in the bulk or on the graphene surface) can be useful for increasing electrical conductivity in graphene films and buckypapers; this issue of contact resistance would also affect the maximum attainable electrical conductivity in graphene-filled polymer nanocomposites. Dispersant removal is also desirable in graphene nanocomposites because excess dispersants may act as diluents, which affects thermal and mechanical properties; similarly, the presence of dispersants can hinder nanofiller-polymer load transfer [1,7] (note that high-temperature annealing is typically not an option in the case of graphene/polymer composites).…”

“…PVP is a polymer which stabilizes graphene by physical adsorption and steric hindrance [1,16,19]. In contrast, PSA is an aromatic molecule that non-covalently bonds to graphene by p-p stacking and stabilizes the dispersion by electrostatic repulsion [2,20]. In this study, we distinguish between the removal of excess (unabsorbed) dispersant from the liquid bulk as well as removal of dispersant from the graphene surface.…”