Further analysis has shown that the average fiber diameter is around 1200 nm and after Contact Angle (CA) measurements has justified the hydrophobic behaviour of those matrices.
These include the rheological behaviour of the matrix melt, the particle incorporation method, interactions of the particles and the matrix before, during and after mixing, and the changing particle distribution during solidification.
In the following, the effective viscosity tensor is estimated using a mean field theory taking into account the linear viscous behaviour of the matrix material, the geometry of the fibers, and their orientation distribution.
Other models accounting for the coupling between the mechanical behaviour of the matrix and the fluid dynamics include the Hassanizadeh model (Hassanizadeh et al. 2002) and the Barenblatt Biot model (Barenblatt and Gilman 1987).
The last section of the paper is devoted to more recent findings concerning the influence of particle size of the components on the percolation threshold of the matrix forming polymer, and therefore on the release behaviour of the matrix.
Mechanism-based constitutive equations which consider work hardening, strain rate and grain growth effects were used to describe the high-temperature deformation behaviour of the matrix.
The viscous behaviour of the matrix is assumed to be linear, isotropic and incompressible given by (boldsymbol {sigma }^{mathrm {m}} = mathbb {V}^{mathrm {m}} [boldsymbol {D}^{mathrm {m}}]) with the isotropic matrix viscosity mathbb{V}^{mathrm{m}} = 3eta_{mathrm{v}} mathbb{P}_{1} + 2eta_{mathrm{s}} mathbb{P}_{2}, (6).
Calculations well agree with experimental data and show that, even if cracks start at GO sheet edges due to stress concentrations, crack propagation is hindered by the nonlinear behaviour of the matrix.
