Robust galactomannan/graphene oxide film with ultra-flexible, gas barrier and self-clean properties

This study examines a facile technology to manufacture food packaging alternatives with superior mechanical, ultra-flexible, gas barrier and self-cleaning properties, based on green and benign starting materials. A novel galactomannan (GM) was isolated from the Sesbania cannabina seeds, which was used as a matrix for the fabrication of GM-based films. Inspired by the brick-and-mortar structure of natural nacre, a facile method was adopted to fabricate an artificial nacre based on the self-assembly of GM and borate crosslinked graphene oxide (GO). These GM/GO composites are ultra-flexible, which can be folded into various shapes. The tensile strength reached 135.54 MPa which is 2.40 times that of the pure GM film. In addition, after coating with the poly (dimethylsiloxane) (PDMS), these films became hydrophobic (WCA around 120 degrees) with self-cleaning properties. Our study further revealed that the oxygen and water vapor permeabilities were improved with the introduction of GO and PDMS coating.