Xylan-cellulose films: Improvement of hydrophobicity, thermal and mechanical properties

Xylan-rich hemicellulose from corn cob has been used for new material elaboration. Commercial cellulose was used as reinforcement in different percentages to improve properties of the films. Two types of composites were elaborated by solvent casting. Hydrophilic films, composed by bleached hemicellulose (BH), unmodified cellulose and glycerol as plasticizer, and hydrophobic films formed by acetylated bleached hemicellulose (BAH) and acetylated cellulose. The degree of substitution of BAH was 1.8 and acetylated cellulose presented a degree of substitution of 0.54. Thermal and mechanical properties of films were analyzed. A significant improvement was observed in the thermal behavior of hydrophobic films (T-max similar to 368 degrees C) respect to hydrophilic films (T-max similar to 300 degrees C). Although the addition of cellulose clearly increase the properties of both type of films, hydrophobic films (Young's modulus similar to 2300 MPa, strength similar to 44.1 MPa, strain at break similar to 5.7%) showed better mechanical properties than hydrophilic films (Young's modulus 3 MPa, strength similar to 3.3 MPa, strain at break similar to 5.3%). (C) 2014 Elsevier Ltd. All rights reserved.