Quantification of gas permeability of epoxy resin composites with graphene nanoplatelets

Publication date: Available online 17 October 2019Source: Composites Science and TechnologyAuthor(s): Q.J. Zhang, Y.C. Wang, C.G. Bailey, Oana M. Istrate, Zheling Li, Ian Kinloch, Peter M. BuddAbstractThis paper presents the development and validation of a numerical simulation method using the Lattice Boltzmann Method (LBM) to predict the permeability of epoxy resin (ER) composites with graphene nanoplatelets (GNPs).Gas permeability tests were carried out for a series of GNP/ER nanocomposites with different loadings and diameters of GNPs. The experimental results confirm that inclusion of GNPs in ER significantly decreased the effective gas permeability, with the highest reduction of 66% when the GNP loading was 3 wt%. The effects of using different diameters of GNPs show that using GNPs of 25 μm in diameter achieved less reduction in gas permeability than using GNPs of smaller diameters of 5 and 15 μm at the same loading of 1 wt%. This unexpected result has now been explained by the developed numerical model.The microstructures of GNPs filled ER composites were numerically reconstructed for the relative gas permeability prediction model using LBM. The 3D X-ray CT scan images clearly show agglomeration of GNPs, in particular when the diameter of GNPs is large (25 μm), due to strong van der Waals forces. An agglomeration sub-model was thus incorporated when numerically constructing the microstructure of GNPs filled ER composites. Agglomeration of GNPs results in...
Source: Composites Science and Technology - Category: Science Source Type: research