Novel Cellulose Films Obtained by the Combination of High-Pressure and Cellulase Treatments

Abstract

This research study focused on the use of technologies such as high-pressure processing (400 MPa for 15 min, HPP) and enzymatic hydrolysis (with cellulase) to process eucalyptus pulp, subsequently the pulp submitted to carboxymethylation to produce cellulose films and investigate their properties. The results revealed that the combination of HPP and cellulase resulted in the production of partially transparent and smoother films. As for mechanical properties, this combination resulted in a 2.7-fold increase in the tensile strength (TS) value, a 35.5-fold increase in the elongation at break (EAB) value, and a 1.4-fold increase in the moisture content of the films. The crystallinity index (CrI) was also increased by HPP and enzymes, resulting in a 6.6-fold increase, compared to the control film. On the other hand, the combined use of HPP and enzymatic hydrolysis resulted in similar contact angle (CA) values on both sides of the films, but in the bottom side, when compared to the control film, a 2.1-fold decrease was observed. Furthermore, the water vapor permeability (WVP) of the films increased 1.8-fold. Finally, the thermal resistance of the films was slightly reduced when either HPP, enzymatic or both treatments were used on the cellulose pulp. In general, this work showed a new potential way to produce cellulose films with novel and potentially tailor-made properties.