Shear-stiffening cellulose nanofiber gels with tuneable mechanical characteristics
2011 (English)In: 241St National Meeting And Exposition Of The American Chemical Society (Acs), 2011, Vol. 241, 131-- p.Conference paper, Presentation (Refereed)Text
Gels have been synthesized from the renewable, strong and low cost cellulose nanofibres; nanofibrillated cellulose (NFC). The gels are shown to exhibit pronounced shear-stiffening properties and large extensibility (above 100%). The stiffening is due to strain induced orientation of the nanofibers, which is enabled by the free rotation at the particle-particle joints. The gels are synthesized from low concn. aq. NFC solns. By decreasing the electrostatic double-layer repulsion between the NFC fibrils, aggregation is initiated and a fluid-gel transition occurs. This transition can be detected within a range of vol. fractions. We characterize the gel microstructures using dynamic light scattering and the mech. properties using a rheometer. The mech. properties of these gels are tuneable; significantly different properties are seen if gels are formed by reducing pH or by increasing ionic strength. It is also obsd. that the properties of the gels depend on the type of counter-ion.
Place, publisher, year, edition, pages
2011. Vol. 241, 131-- p.
Paper, Pulp and Fiber Technology
IdentifiersURN: urn:nbn:se:liu:diva-125212OAI: oai:DiVA.org:liu-125212DiVA: diva2:903638
241st National Meeting and Exposition of the American Chemical Society (ACS), Anaheim, CAU united States, March 27-31, 2011