Carboxymethylated nanofibrillated cellulose: rheological studies
- 1.4k Downloads
The rheological properties of carboxymethylated nanofibrillated cellulose (NFC), investigated with controlled shear rate- and oscillatory measurements, are reported for the first time. It was shown that the rheological properties of the studied system are similar to those reported for other NFC systems. The carboxymethylated NFC systems showed among other things high elasticity and a shear thinning behaviour when subjected to increasing shear rates. Further, the shear viscosity and storage modulus of the system displayed power-law relations with respect to the dry content of the NFC suspension. The exponential values, 2 and 2.4 respectively, were found to be in good agreement with both theoretical predictions and published experimental work. Furthermore, it was found that the pulp consistency at which NFC is produced affects the properties of the system. The rheological studies imply that there exists a critical pulp concentration below which the efficiency of the delamination process diminishes; the same adverse effect is also observed when the critical concentration is significantly exceeded due to a lower energy input during delamination.
KeywordsNanofibrillated cellulose Carboxymethylation Gel Rheology Viscosity Homogenization
Ann-Marie Runebjörk, Åsa Blademo, and Åsa Engström are thanked for their competent supporting work. Mikael Ankerfors is thanked for helpful discussions. Billerud-Korsnäs, Borregaard, De la Rue, Hansol, Holmen, Kemira, Korsnäs, Metsä Group, Stora Enso, Södra, UPM, and Evergreen Packaging are acknowledged for their financial support.
- De Gennes PG (1979) Scaling concepts in polymer physics. Cornell Univ Press, IthacaGoogle Scholar
- Eichhorn SJ, Dufresne A, Aranguren M, Marcovich NE, Capadona JR, Rowan SJ, Weder C, Thielemans W, Roman M, Renneckar S, Gindl W, Veigel S, Keckes J, Yano H, Abe K, Nogi M, Nakagaito AN, Mangalam A, Simonsen J, Benight AS, Bismarck A, Berglund LA, Peijs T (2010) Review: current international research into cellulose nanofibres and nanocomposites. J Mater Sci 45(1):1–33CrossRefGoogle Scholar
- Herrick FW, Casebier RL, Hamilton JK, Sandberg KR (1983) Microfibrillated cellulose: morphology and accessibility. J Appl Polym Sci Symp 37:797–813Google Scholar
- Lindström T, Aulin C, Naderi A, Ankerfors M (2014) Microfibrillated cellulose. In: Encyclopedia of polymer science and technology, John Wiley & Sons Inc., Hoboken, pp 1–34. doi: 10.1002/0471440264.pst614
- Pääkkö M, Ankerfors M, Kosonen H, Nykänen A, Ahola S, Österberg M, Ruokolainen J, Laine J, Larsson PT, Ikkala O, Lindström T (2007) Enzymatic hydrolysis combined with mechanical shearing and high-pressure homogenization for nanoscale cellulose fibrils and strong gels. Biomacromolecules 8(6):1934–1941. doi: 10.1021/bm061215p CrossRefGoogle Scholar
- Sandquist D (2013) New horizons for microfibrillated cellulose. Appita J 66:156–162Google Scholar
- Turbak AF, Snyder FW, Sandberg KR (1983) Microfibrillated cellulose, a new cellulose product: properties, uses, and commercial potential. J Appl Polym Sci Symp 37:815–827Google Scholar