Effects of particle stiffness on the extensional rheology of model rod-like nanoparticle suspensions
Publication Date
2019
Journal or Book Title
Soft Matter
Abstract
The linear and nonlinear rheological behavior of two rod-like particle suspensions as a function of concentration is studied using small amplitude oscillatory shear, steady shear and capillary breakup extensional rheometry. The rod-like suspensions are composed of fd virus and its mutant fdY21M, which are perfectly monodisperse, with a length on the order of 900 nm. The particles are semiflexible yet differ in their persistence length. The effect of stiffness on the rheological behavior in both, shear and extensional flow, is investigated experimentally. The linear viscoelastic shear data is compared in detail with theoretical predictions for worm-like chains. The extensional properties are compared to Batchelor's theory, generalized for the shear thinning nature of the suspensions. Theoretical predictions agree well with the measured complex moduli at low concentrations as well as the nonlinear shear and elongational viscosities at high flow rates. The results in this work provide guidelines for enhancing the elongational viscosity based on purely frictional effects in the absence of strong normal forces which are characteristic for high molecular weight polymers.
DOI
http://dx.doi.org/10.1039/c8sm01925h
Pages
833-841
Volume
15
License
UMass Amherst Open Access Policy
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Recommended Citation
Lang, Christian; Hendricks, Jan; Zhang, Zhenkun; Reddy, Naveen K.; Rothstein, Jonathan P.; Lettina, M. Paul; Vermant, Jan; and Clasen, Christian, "Effects of particle stiffness on the extensional rheology of model rod-like nanoparticle suspensions" (2019). Soft Matter. 621.
http://dx.doi.org/10.1039/c8sm01925h