Extensional viscosity of microfibrillated cellulose suspensions
Artikel i vetenskaplig tidskrift, 2014

The extensional properties of micro fibrillated cellulose (MFC)-suspensions at different fibril concentrations and with different amounts of added sodium chloride were evaluated. The MFC-suspensions were obtained by diluting a stock solution consisting of 0.95 wt.% cellulose with either deionized water or sodium chloride solution, giving a series of different concentrations and sodium chloride contents. The extensional viscosities of the suspensions were measured utilizing contraction flow geometry. Here the specimens were forced through a hyperbolic nozzle and the required pressure drop over the nozzle was measured. The extensional viscosity exhibited an extensional-thinning behaviour over the extensional strain rates used. Furthermore the extensional viscosity decreased with decreasing concentration of the suspensions, in similarities with the shear properties of the specimens. For the suspensions containing sodium chloride, the extensional viscosity appeared to increase when the concentration of sodium chloride was increased. But excessive amounts of added sodium chloride promoted an agglomeration of the suspensions.

suspensions

microfibrillated cellulose

extensional viscoity

reologi

Författare

Tobias Moberg

Chalmers, Material- och tillverkningsteknik, Polymera material och kompositer

Mikael Rigdahl

Chalmers, Material- och tillverkningsteknik, Polymera material och kompositer

Wallenberg Wood Science Center (WWSC)

Mats Stading

Chalmers, Material- och tillverkningsteknik, Polymera material och kompositer

Emma Levenstam Bragd

Swedish Institute for Food and Biotechnology

Carbohydrate Polymers

0144-8617 (ISSN)

Vol. 102 409-412

Drivkrafter

Hållbar utveckling

Ämneskategorier

Materialteknik

Styrkeområden

Materialvetenskap

DOI

10.1016/j.carbpol.2013.11.041