From Bolaina Blanca Wood Fibers to Antimicrobial Films: Characterization and Application in the Food Industry Using Copper Nanoparticles

The isolation and use of polymers from non-traditional sources for the development of functional materials is becoming increasingly popular. One of the aspects of these developments is the inclusion of additives, such as antimicrobial agents, that provide added value to these polymers. This work discusses the preparation of a nanocomposite using isolated nanocellulose from bolaina blanca wood, polyvinyl alcohol, and copper nanoparticles. Extensive characterization of the chemical, mechanical, thermal, morphological, and other film properties revealed that the films formulated with highly refined microfibrillated cellulose (CMF) exhibited the best overall performance. The improved mechanical and barrier properties of these films support their possible use in food packaging. The addition of copper nanoparticles (CuONP) provided an inhibition ring for E. coli growth in all the cases when it was presented, with the biggest inhibition area when using the CMF20 which contains 79.20% of CMF. Overall, the results obtained in this work show the potential of alternative-sourced CMF and CuONP for the generation of green, sustainable, and active packaging.