Tannic acid crosslinked chitosan-guar gum composite films for packaging application

Area of Science:

• Materials Science
• Polymer Science
• Biomaterials Engineering

Background:

• Chitosan (CH) and guar gum (GG) are biocompatible polymers with potential for film applications.
• Developing advanced composite materials with improved properties is crucial for various industries.
• Crosslinking agents are essential for enhancing the stability and functionality of polymer composites.

Purpose of the Study:

• To prepare and characterize chitosan-guar gum composite films crosslinked with tannic acid (TnA).
• To evaluate the impact of tannic acid concentration on the physicochemical, mechanical, and antioxidant properties of the films.
• To assess the suitability of these composite films for packaging applications.

Main Methods:

• Composite films were prepared using the solution casting method.
• Films were crosslinked with tannic acid and treated with aqueous ammonia.
• Characterization involved IR spectroscopy, X-ray diffraction, thermogravimetric analysis, and assessment of various physicochemical properties.
• Mechanical strength, water contact angle, water vapor permeability, opacity, and antioxidant activity were evaluated.

Main Results:

• Crosslinking with tannic acid significantly increased the amorphous domains of the chitosan-guar gum films.
• The composite films exhibited reduced moisture content, swelling, and water solubility, becoming more hydrophobic.
• Improved UV absorption and enhanced mechanical strength were observed, dependent on tannic acid concentration.
• Antioxidant activity was significantly improved, while water vapor permeation remained comparable to pure chitosan films.

Conclusions:

• Chitosan-guar gum composite films crosslinked with tannic acid demonstrate enhanced hydrophobicity, mechanical strength, UV absorption, and antioxidant properties.
• The tunable properties make these films promising candidates for advanced packaging solutions.
• The developed composite films offer a sustainable alternative for food and other packaging applications.