Investigation of graphene and nanocellulose hybrid films as a barrier material in packages

Sammanfattning: In this report, hybrid films of carboxymethylated cellulose nanofibrils (CNF) and graphene nanosheets (GNs) have been prepared to evaluate if the GNs can enhance the barrier properties of the CNF films. CNF already possess great barrier properties at low relative humidity (RH) but it is drastically lowered when the RH reaches above 50% due to its strong hydrophilicity of CNF. This report shows that the water vapour permeability(WVP) of the hybrid film can be lowered more than 25 times at 50% RH in comparison to the pure nanocellulose film due to the hydrophobic properties and good impermeability properties of GNs. The report also shows how different parameters such as sonication time, starting materials and ratios should be chosen when making films. A scale-up part of the project is also done in collaboration with the industry where an easier way of dispersion and a faster application of the film is evaluated.