Fabrication of Biosurfactant Enhanced Cellulose-Ca ²⁺Zn ²⁺ Crosslinked Films: A Sustainable Replacement for...

Cellulose-based films are popular in curent market as eco-friendly alternatives, but their high hydrophilicity leads to poor moisture resistance and reduced barrier properties. Incorporating biosurfactants (BS) into these films offers an effective strategy to modify surface properties and improve barrier performance. In the current study, cellulose film was developed using ZnCl₂ facilitated dissolution and CaCl₂ mediated crosslinking followed by the incorporation of BS MS48 of (0.6% and 1.25%) concentrations. The BS (1.25%) incorporated film exhibited better performance, with higher tensile strength (1.05 N/mm²), lower water vapour transmission (24.3 ± 2.1 g/m²/day), reduced moisture content (20.4 ± 1.3%) and improved transparency (81.14 ± 0.94%). Field Emission Scanning Electron Microscopy (FE-SEM), revealed cellulose films had a wrinkled, poorly organized structure, whereas cellulose BS blended films exhibited a well-defined, uniform fibrillar network. The X-ray Photoelectron Spectroscopy (XPS) showed that BS bonded with cellulose by interaction of hydroxyl groups in cellulose with phosphate and nitrogen groups of the BS. Structural studies using FE-SEM, XPS, Fourier Transform Infrared (FTIR) and Raman Spectroscopy, X-ray Diffraction (XRD) showed BS - cellulose films were uniform, with filamentous network, and modification in crystallinity. BS films degraded faster than the control cellulose films, indicating that the introduction of BS enhanced their biodegradability. Packaging studies, conducted on coriander leaves showed reduced weight loss and improved moisture in the BS incorporated cellulose films. Therefore, the developed BS cellulose films could be a green alternative to plastic films.