A biodegradable alginate/chitosan hydrogel based nonwoven from pre-consumer cotton waste and virgin wool for food packaging

The municipal waste is polluting the environment by releasing harmful substances. There is a demand for eco-friendly food packaging with higher shelf life. In this study, a biodegradable nonwoven for food packaging was developed using cotton waste and alginate/chitosan hydrogel. Firstly, needle-punched nonwovens were prepared from two different kinds of cotton waste (comber noil and card-fly) and wool fibers. The prepared nonwovens were immersed in a solution of alginate/chitosan followed by cross-linking with sodium chloride which resulted in formation of layers of hydrogel on/into nonwovens. The developed nonwovens for food packaging were characterized by using FTIR, DSC, SEM, air permeability and water absorbency tests. Moreover, mechanical strength and antibacterial evaluation of prepared nonwovens was also done. The properties of developed packaging materials are dependent on fiber type and concentration of hydrogel. The water absorption rate is highest (1 sec to 25 sec) in the case of wool fiber-based hydrogel nonwoven with tensile strength ranging from 65 N to 90 N. Moreover, all the developed samples of nonwoven alginate/chitosan hydrogel showed good antibacterials and air barrier (360 mm/sec to 620 mm/sec properties). The results indicate that the nonwoven alginate/chitosan hydrogel holds significant promise as an environmentally friendly substitute for food packaging materials.