TY  - JOUR
AU  - Lang, Christian
AU  - Hendricks, Jan
AU  - Zhang, Zhenkun
AU  - Reddy, Naveen K.
AU  - Rothstein, Jonathan P.
AU  - Lettinga, M. Paul
AU  - Vermant, Jan
AU  - Clasen, Christian
TI  - Effects of particle stiffness on the extensional rheology of model rod-like nanoparticle suspensions
JO  - Soft matter
VL  - 15
IS  - 5
SN  - 1744-683X
CY  - London
PB  - Royal Soc. of Chemistry
M1  - FZJ-2018-06327
SP  - 833-841
PY  - 2019
AB  - 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.
LB  - PUB:(DE-HGF)16
C6  - pmid:30488939
UR  - <Go to ISI:>//WOS:000457540000022
DO  - DOI:10.1039/C8SM01925H
UR  - https://juser.fz-juelich.de/record/857059
ER  -