Viscoelasticity of single wall carbon nanotube suspensions

2020-02-12 01:58:52

SWNTs nanotubes suspensions dependent Percolation

责任者: Hough, L.A.;Islam, M.F.;Janmey, P.A.;Yodh, A.G. 单位: Dept. of Phys. & Astron., Univ. of Pennsylvania, Philadelphia, PA, USA 来源出处: Physical Review Letters(Phys. Rev. Lett. (USA)),2004/10/15,93(16):168102-1 摘要: We investigate the viscoelastic properties of an associating rigid rod network: aqueous suspensions of surfactant stabilized single wall carbon nanotubes (SWNTs). The SWNT suspensions exhibit a rigidity percolation transition with an onset of solidlike elasticity at a volume fraction of 0.0026; the percolation exponent is 2.3±0.1. At large strain, the solidlike samples show volume fraction dependent yielding. We develop a simple model to understand these rheological responses and show that the shear dependent stresses can be scaled onto a single master curve to obtain an internanotube interaction energy per bond ≈40kBT. Our experimental observations suggest SWNTs in suspension form interconnected networks with bonds that freely rotate and resist stretching. Suspension elasticity originates from bonds between SWNTs rather than from the stiffness or stretching of individual SWNTs 关键词: carbon nanotubes;percolation;rheology;suspensions;viscoelasticity;yield stress;viscoelastic properties;associating rigid rod network;aqueous suspensions;single wall carbon nanotubes;surfactant stabilized nanotubes;rigidity percolation transition;solidlike elasticity onset;volume fraction dependent yielding;rheological responses;shear dependent stresses;master curve;internanotube interaction energy per bond;interconnected networks;shear modulus;linear viscoelasticity;nonlinear viscoelasticity;C