The TOCN films prepared from softwood cellulose
were transparent and flexible and had extremely low coefficients of thermal expansion caused by high crystallinity
of TOCN. Moreover, oxygen permeability of a polylactic acid (PLA) film drastically decreased to about 1/750 by
forming a thin TOCN layer on the PLA film. Hydrophobization of the originally hydrophilic TOCN films was
achieved by treatment with alkylketene dimer. These unique characteristics of the TOCN films are promising for
potential applications in some high-tech materials.