Natural cellulose fibres are made from long microfibrils of cellulose, of varying degrees of crystallinity, depending on the source. By careful acid hydrolysis with sulphuric acid, it is possible to dissolve the non-crystalline portions, leaving rod-like nanocrystals of cellulose I.
The nanocrystals are stabilized in aqueous suspension by sulphate groups on the surface. At a critical concentration, the suspensions form a chiral nematic ordered phase. ["Helicoidal Self-ordering of Cellulose Microfibrils in Aqueous Suspension," J.-F. Revol, H.Bradford, J. Giasson, R.H. Marchessault and D.G. Gray, Int. J. Biol. Macromol., 14, 170-172 (1992).]
The equilibrium between ordered and disordered phases is sensitive to counterions, ionic strength, and added polymers. ["Effect of Counterions on Ordered Phase Formation in Suspensions of Charged Rodlike Cellulose Crystallites." Xue Min Dong and Derek G. Gray, Langmuir, 13, 2404-2409 (1997).]