Spin self-assembly of highly ordered multilayers of graphene-oxide sheets for improving oxygen barrier performance of polyolefin films

Polypropylene films with ultra-high oxygen barrier properties have been created using a combination of two-dimensional graphene oxide sheets and spin self-assembly for the highly ordered layer-by-layer structure. Highly transparent and extremely flat barrier films, with a thickness of several tens of nanometers and significantly reduced oxygen permeability, were easily assembled, layer by layer, using negatively charged graphene oxide monolayers and positively charged poly(allylamine hydrochloride). We also investigated the effect of the structural orderliness of nanosheets on the gas-barrier properties, using different deposition methods, including spin layer-by-layer, dip layer-by-layer, and mixture spin-coating deposition. Comparing the experimental data with theoretical models, the relationship between the structural order of nanosheets and the gas-barrier performance was clearly explained.