Sandwich films with graphene oxide nanocores: gas barrier properties

Single polymer composite films with PMMA facings and PMMA or PMMA-Graphene Oxide (GO) electrospun nano-fibre mat core were manufactured with an intention of application in various facets of engineering. Design of experiments based on mixture analysis was used to identify the solution concentration for obtaining uniform fibre diameters and their distribution throughout the electrospun core. The oxygen gas transmission rate (O2GTR) and the permeance of the film (PO2) were tested in OX-TRAN® Model 2/10, per standard ASTM F 2622 and modelled using series and parallel configuration. The sandwich films were manufactured using vacuum assisted compression moulding by laying the electrospun core between two thin layers of PMMA films. The analysis shows that 23% PMMA and 2% GO concentrations in the solution give approximately uniform fibre diameters and dispersion throughout the mat. The experimental results from the oxygen barrier tests revealed oxygen permeability values in the negative range for the sandwich films compared to 2.59 cc-mm/m2 day for the neat PMMA films. The theoretically calculated values of permeation through the sandwich films were found to be in range of 0- 0.0224 cc-mm/m2 day The presence of GO, as low as 1%, in the nanofibre mat enhanced the oxygen barrier of the sandwich films by more than 100%.