Rheology of Concentrated Carbon Nanotube Suspensions
K HobbieE, J FryD
The rheological properties of non-Brownian carbon nanotube suspensions are measured over a range of nanotube volume fractions spanning the transition from semi-dilute to concentrated. The nanotubes are `sticky' and form a quiescent elastic network with a well-defined shear modulus and yield stress that both depend strongly, although distinctly, on nanotube volume fraction. We compare controlled-strain and controlled-stress measurements of yielding in shear flow, and we study the effect of slow periodic stress reversal. Our measurements suggest a universal scaling of both the linear viscoelastic and steady-shear response. The former allows us to extract the elastic shear modulus of semi-dilute nanotube networks for values that are near or below the resolution limit of the rheometers used, while the latter provides a similar extrapolation of yield stress. Our measurements highlight interesting differences, and even some striking similarities, between viscometric and linear-viscoelastic response.
and FryD, J.
Rheology of Concentrated Carbon Nanotube Suspensions, Journal of Rheology, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=852605
(Accessed December 5, 2023)