Influence of Structure of Skeleton Materials on Permeability of Liquids

Abstract

Permeability of various liquids in pores of skeleton materials (porous samples from powders of reduced iron and alloy steel Cr-Ni-Ti, porous ceramic ZrO2/CaO and carbonisates of polyvinyl alcohol) is analysed. It is shown, that at the flow of liquid monomers through ceramic and metal porous materials the flow rate depends on pressure difference rectilinearly. Such rectilinear dependence is absent at the flow of liquids of high viscosity (for example, solutions of polymers) through skeleton materials with fine pores (diameter of pores < 50 μm – 60 μm). During the research of permeability of low viscosity liquids in porous capillaries with the diameter less than 100 μm, an effect of obliteration is found. This effect is caused by adsorption processes in boundary layers and increase of viscosity of part of a liquid interacting with solid surface. Analysis of processes of permeability of styrene, methyl methacrylate (ММА) in porous media with high activity of a surface (carbonaceous polymer) has shown that the development of obliteration is promoted by more developed fine porosity, tortuosity of pores and increase of the rate of flow of a liquid phase (pressure difference). Various functional groups formed on the surface of pores of carbonisate interact with molecules of liquids (monomers) and form intermediate buffer layers of by-products of reaction. Formation of such buffer layers changes resistance of skeleton system to permeability of a liquid phase and, thus, promotes development of effect of obliteration.