Development of hybrid chitosan/zinc oxide/graphene oxide nanocomposites for potential food packaging application

Abstract

Novel food packaging materials are becoming increasingly necessary and extensive research is underway worldwide towards developing environmentally friendly and bio-based polymers. Among various biopolymers, chitosan is the noticeable and industrially viable food packaging material and is the second most naturally available biopolymer after cellulose. This study is based on the reinforcing hybrid nanomaterials of zinc and graphene oxides into the chitosan matrix to produce a bio-based food packaging material with improved antimicrobial properties, high water resistance and thermally stable hybrid chitosan/ZnO/GO nanocomposites. Various characterization techniques such as Raman, FTIR, XRD and FE-SEM confirmed the preparation of nanofillers and their successful encapsulation into the chitosan matrix. The thermal analysis results confirmed a marked rise of 46.5 and 62.1°C at T<inf>25%</inf> and T<inf>50%</inf> respectively of hybrid nanocomposites as compared to neat chitosan. Further, the DTG analysis showed there was a significant rise of 19°C in the maximum degradation temperature for hybrid chitosan/ZnO/GO nanocomposites as compared to neat chitosan. The water vapor permeability of hybrid nanocomposites was reported at a minimum of 1.04 g.mm/m2.h.kPa against the neat chitosan of 2.22 g.mm/m2.h.kPa which confirmed the nanocomposites with improved water resistance. The antimicrobial property tested in presence of Bacillus subtilis (gram-positive bacterium) was reported maximum for hybrid chitosan/ZnO/GO nanocomposites with the highest inhibition zone of 12 mm as compared to the inhibition zone of neat chitosan, chitosan/GO, and chitosan/ZnO of 5 and 10 mm respectively. The increase in the above properties of the hybrid nanocomposites is attributed to the combined effect of hybrid nanofillers as compared to the nanocomposites with the use of single nanofillers. © International Journal of Sustainable Building Technology and Urban Development.