Author/Authors :
Wang، نويسنده , , H. and Christopherson، نويسنده , , G.T. and Xu، نويسنده , , Z.Y. and Porcar، نويسنده , , L. and Ho، نويسنده , , D.L. and Fry، نويسنده , , D. and Hobbie، نويسنده , , E.K.، نويسنده ,
Abstract :
We report a combined shear small-angle neutron scattering (shear-SANS) and rheo-optical study of dilute aqueous suspensions of SWNT bundles dispersed using ionic surfactants. Both shear-SANS and flow birefringence reveal weak shear-induced alignment of SWNT bundles along the direction of flow. In terms of a nematic order parameter, the degree of alignment is found to increase with the shear rate, reaching ca. 0.08 at 2000 s−1. Addition of a soluble polymer to the SWNT suspensions diminishes shear-induced alignment. The factors limiting shear alignment in dilute SWNT suspensions are discussed.
