Development of citric acid crosslinked biodegradable chitosan/hydroxyethyl cellulose/organo-modified nanoclay composite films as sustainable food packaging materials

ABSTRACT

Chitosan/hydroxyethyl cellulose-based sustainable food packaging composite films (CS/HEC/NC) crosslinked with citric acid (CA) and containing organophilic nanoclay were prepared using the solvent casting method. The physical, thermal, mechanical and barrier properties of as-synthesized composite films were evaluated toward their use as an alternative to petroleum-based polymers. A considerable improvement was observed in surface hydrophobicity, water resistance, barrier properties, tensile strength, and thermal stability of the composite films with increasing nanoclay ratio. CS/HEC/NC3 film loaded with 5 wt% nanoclay exhibited the best physical properties with percent enhancements of 22.94°C, 52.56% and 36.53° in maximum degradation temperature, tensile strength, and water contact angle, respectively, over the neat CS/HEC film. In addition, low permeabilities against water vapor (1.240 × 10⁻¹¹ gs⁻¹m⁻¹Pa⁻¹) and oxygen (1.12 × 10⁻¹⁶ m³s⁻¹m⁻¹Pa⁻¹), and also strong antibacterial activity against Staphylococcus aureus and Escherichia coli were obtained for this film. The food preservation effects of CS/HEC/NC composite films against cherry tomatoes were also studied, and less than 20% mass loss was achieved in five weeks. Consequently, CS/HEC/NC composite films can be considered competitive packaging materials with great potential to improve safety and quality and extend the shelf life of packaged foods.

KEYWORDS:

• Biopolymer
• chitosan
• food packaging
• hydroxyethyl cellulose
• nanoclay

Acknowledgments

The author would like to thank Elif Şanlı and Esra Ketenci for their assistance in synthesizing film materials.

Disclosure statement

No potential conflict of interest was reported by the author.

Additional information

Notes on contributors

Yasemin Balçık Tamer

Yasemin Balçık Tamer got her BSc degree in Chemistry and Chemical Engineering from Yildiz Technical University in 2006 and 2007, respectively. She completed her master’s and doctoral study in the Department of Chemistry of Yildiz Technical University in 2008 and 2014, respectively. She is now a lecturer in the Department of Polymer Material Engineering at Yalova University. Her research interests are hydrogels, polymer composites, biopolymers, and emulsion polymerization.