CELLULOSE FILMS WITH AT LEAST ONE HYDROPHOBIC OR LESS HYDROPHILIC SURFACE

摘要

A method for the production of cellulose films with at least one hydrophobic or less hydrophilic surface, or with at least one surface with a water contact angle (&thetas;) in a range from 55° to less than 100° is described. The method involves contacting the cellulose material with a hydrophobic solid material during the preparation of the cellulose films or with a vapour of a non-polar or polar aprotic solvent during or after the preparation of the cellulose films. Examples of the cellulose material are cellulose filaments (CF) made to have at least 50% by weight of the filaments having a filament length up to 350 μm and a filament diameter between 100 and 500 nm from multi-pass, high consistency refining of wood or plant fibers, and commercially-available sodium carboxymethyl cellulose. Examples of the hydrophobic solid material are hydrophobic polymers, poly(methylpentene) and poly(ethylene). Examples of the non-polar solvent are hexane and toluene. Examples of the polar aprotic solvent are acetone and ethyl acetate.