Permeation of liquids

Yazawa, T., H. Nakamichi, H. Tanaka and K. Eguchi. 1988. Permeation of liquid through a porous glass membrane with surface modification. Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi 96(1) 18-23. 

D.R. Paul, J.D. Paciotti and O.M. Ebra-Lima, Hydraulic Permeation of Liquids Through Swollen Polymeric Networks, J. Appl. Polym. Sci. 19, 1837 (1975). 

There are also standard specifications for testing the permeation of liquid chemicals through protective clothing [59]. and for the permeation of vapor through the walls of a hose [60.61]. 

Special problems occur in the permeation of liquids through films when the liquids swell the film. Equation (7-58) is replaced by... 

Sungpet, A., Way, J.D., Koval, C.A. and Eberhart, M.E. 2001. Silver doped Nafion-poly(pyrrole) membranes for facilitated permeation of liquid-phase olefins. 

ASTM F2298 Standard Test Method for Permeation of Liquids and Gases through Protective Clothing Materials under Conditions of Continuous Contact... 

Tsuru, T., Sudoh, T.,Kawahara, S., Yoshioka.T., and Asaeda, M. (2000). Permeation of liquids through inorganic nanofiltration membranes, J Colloid Inter/ Sd 228 292-296. 

Cell geometry (i.e., open versus closed cells, size, and shape), which depends on the process used for the production of the foamed plastic, determines certain properties, thereby influencing suitable types of applications. In open-cell foams, the gas phase is inevitably air thus, open-cell foams offer little resistance to the permeation of liquids and gases, making them only most suitable for acoustical insulation and in cushioning applications. In contrast, in closed-cell foam, the cell walls act as a barrier to gases and liquids. Therefore, closed-cell foams have lower permeability than open-cell foams. If the gas phase in closed-cell foams has low thermal conductivity, then this closed-cell foam will provide better thermal insulation properties than open-cell foams that are air filled. 

There seems to be a historical reason for the difference in these two approaches. The solution-diffusion approach was established for the permeation of liquid and gas through the membrane before reverse osmosis membranes of practical usefulness were developed by the phase-inversion technique. Dense membranes without asymmetricity were prepared from polymeric materials, and their transport properties were measured, assuming that the membranes were defect-free and the transport parameters so produced were the values intrinsic to the material. The membrane with the highest separation capacity for a given polymer was believed to be that which could exhibit the transport properties intrinsic to the polymer. The goal of membrane production engineering was to ensure the membrane intrinsic transport properties of the polymeric material. This approach is still popular in the membrane manufacturing industry. 

The permeation of liquids through sand, gravel or soil is governed by the pressure head and wetting of the solid by the liquid (surface tension). It is the object of this experiment to show this effect and how it might be possible to circumvent the effect. 

It is often noted that water vapor may have more effect on the coating than does Uqnid water. For nonporous materials, there is no theoretical difference between permeation of liquid water and that of water vapor [4]. Coatings, of course, are not solid, but rather contain a good deal of anpty space, for example ... 

Fibrous superabsorbent polymers have larger surface areas than particulate ones. Furthermore, they have excellent diffusion and permeation of liquid by capillary effect and thus high absorbencies are expected. These fibers can be manufactured with ordinary structural fibers such as cellulose fibers or synthetic fibers by the airlaid technique, and the potential for further development is high. 

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