| abstract |
Mono-layer thin film membranes are provided which are ultraporous. Such mono-layers are formed having a thickness on the order of about 1.2 to 150 nanometers, by a variety of polymerization, cross-linking, and film treatment processes to achieve the development of controlled pore sizes in the ultraporous size range corresponding to molecular weight cutoff values of from 500 to about 1,000,000. Such thin film mono-layer membranes are ordinarily supported on a microporous support material, desirably a microporous polymer membrane having a smooth, microporous skin with pore sizes in the range of from about 0.1 microns to about 3 microns, preferably from about 0.1 microns to about 0.5 microns, in diameter. There may be an intermediate gel layer. These membranes are useful for ultraporous, dialysis, and molecular separations. |