title: Adsorption of F127 onto single-walled carbon nanotubes characterized using small-angle neutron scattering.
abstract: Aqueous single-walled carbon nanotube dispersions are often made using polymers from the pluronic family of amphiphilic block copolymers; however, relatively few studies have been conducted using small-angle neutron scattering techniques to discover the mechanism by which they act. SANS results reported here show that a relatively simple core-shell cylinder model can be used to fit data successfully at different contrasts. The results across all contrasts showed that the best fit gave an inner nanotube radius of 10 Å, corresponding to small nanotube bundles with a small amount of water present (20%), and a polydisperse adsorbed layer thickness of 61 Å, with a water content of 94% in the adsorbed layer. The data fitting is thus consistent with a small SWCNT bundle surrounded by an extended and water-swollen F127 adsorbed layer. Comparing the scattering from F127/SWCNT at different contrasts, it has been found that the polymer-decorated SWCNTs are contrast matched at a D2O/H2O volume ratio of 0.36:0.64, corresponding to a scattering-length density of 1.92 × 10(-6) Å(-2).
authors.affiliation: †School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom.
authors.forename: E S
authors.initials: ES
authors.lastname: Kastrisianaki-Guyton
authors.affiliation: ‡Merck Chemicals Ltd., Chilworth Technical Centre, University Parkway, Southampton SO16 7QD, United Kingdom.
authors.forename: L
authors.initials: L
authors.lastname: Chen
authors.affiliation: §ISIS Neutron Source, STFC Rutherford Appleton Laboratory , Didcot, Oxfordshire, OX11 0QX, United Kingdom.
authors.forename: S E
authors.initials: SE
authors.lastname: Rogers
authors.affiliation: †School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom.
authors.forename: T
authors.initials: T
authors.lastname: Cosgrove
authors.affiliation: †School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom.
authors.forename: J S
authors.initials: JS
authors.lastname: van Duijneveldt