摘要 |
<p>Highly asymmetric polyethersulfone membranes prepared from a stable, clear, homogeneous solution or stable colloidal dispersion of polyethersulfone are described. The membranes have a porous skin possessing a high density of skin pores with an average diameter of from about 0.001 micron to about 20 microns. In addition, the membrane has a porous support with an asymmetric region of gradually increasing pore diameters so that the opposite face of the membrane has an average pore diameter that is from about 50 to about 10,000 times the diameter of the skin pores.</p> |