In-House Production and Modification of Biocellulose

The use of cellulose has increased in recent years, resulting in widespread damage to the environment, most critically deforestation, where forests are cleared for wood or the cultivation of crops that produce cellulose. Biocellulose produced by Komagataeibacter xylinus offers a promising alternative, with a unique nanostructure and mechanical strength. This project aims to investigate the effectiveness of modifying biocellulose, using esterification with carboxylic acids and metal ion cross-linking, in increasing the tensile strength of biocellulose and its effect on hydrophobicity. Results showed that carboxylic acids of longer carbon chain length corresponded with a greater increase in biocellulose tensile strength. Esterification of biocellulose led to a reduction in swelling ratio, indicating a rise in hydrophobicity. Metal ion cross-linking of biocellulose increased the tensile strength, with trivalent metal ions having a greater impact on wet biocellulose, and divalent metal ions for dry biocellulose. The properties of increased tensile strength and hydrophobicity of biocellulose may prove to be useful in the medical, manufacturing and food industries, providing a more durable material while simultaneously avoiding the issues that come with the high swelling ratio and low hydrophobicity of unmodified biocellulose.