The structures of the cellulose nan

The structures of the cellulose nanofibers were characterized by TEM after negative staining by PTA. The samples obtained via different nanofibrillation methods and from various raw materi- als exhibit similar morphologies (Fig. 2). TEM images show the presence of very long nanofibers with varying degrees of entan- glement. The widths of single nanofibers are mainly in the range of 2–5 nm (Fig. S1). In higher plants, the diameters of single elemen- tal fibrils are reported to be ∼3 nm (Somerville et al., 2004).