Time-resolved phenomena in cements, clays and porous rocks

Small-angle neutron scattering (SANS) provides a powerful tool in the non-destructive characterization of statistically representative microstructures in technologically important disordered materials. While qualitative microstructural models must be provided by other methods such as transmission electron microscopy (TEM), SANS quantifies the microstructural parameters and can characterize scale-invariant (fractal) disordered materials such as cements, clays and porous rocks. H₂O/D₂O contrast-variation methods have proved particularly useful for investigating the accessibility of different parts of the pore structure and in differentiating between pore-volume access (measured by other methods) and pore-surface accessibility (likely to control sorption and leaching processes). This paper describes SANS studies of disordered porous materials, particularly the hydration of cement and the real-time permeation of water in clay minerals. Other microstructural effects are also considered.