Abstract: The present invention relates to the field synthetic polymeric microfiltration membrane materials that are fabricated to separate liquids from solids contained therein. One aspect of the invention relates to a sulfone polymer membrane with high surface porosity (high pore density) and distinctive asymmetry that can separate solids (i.e., blood cells) from a liquid (i.e., plasma) without the need for centrifugation. The membrane is further rendered hydrophilic through co-casting the sulfone polymer (which is a hydrophobic polymer) with a hydrophilic polymer, such as polyvinylpyrrolidone. Because of these properties and the fact that it requires only a small amount of the solid containing liquid (i.e., whole blood) to be applied to the larger pore surface, the membranes of the invention are highly useful in testing devices for the quick detection of properties or components contained in liquid samples, such as diagnostic applications (i.e., the detection of physiological conditions (i.e.

Abstract: 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.

Abstract: 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.

Abstract: The present invention relates to the field synthetic polymeric membrane materials formed from casting polyvinylidene difluoride (PVDF) polymer solutions and/or dispersions. Membranes formed in accordance with the present invention are all highly porous. Both internally isotropic membranes and highly asymmetric PVDF membranes are disclosed. The membranes of the invention are useful in a variety of microfiltration and ultrathin applications.

Abstract: An improved asymmetric membrane fashioned from a polyimide for the liquid separation of solvents from lube oil. The membrane is based on a fully imidized polymer based on 5(6)-amino-1-(4'-aminophenyl)-1,3,3-trimethylindane polymer and benzophenone tetracarboxylic dianhydride.

Abstract: An improved asymmetric membrane fashioned from a polyimide for the liquid separation of solvents from lube oil. The membrane is based on a fully imidized polymer based on 5(6)-amino-1-(4'-aminophenyl)-1,3-trimethylindane polymer and benzophenone tetracarboxylic dianhydride.

Abstract: An asymmetric membrane and a method for its preparation is disclosed. The membrane is suitable for gas separation, reverse osmosis and pervaporation applications and is characterized in that it is based on a fully imidized 5(6)-amino-1-(4'-aminophenyl)-1,3-trimethylindane polymer having pore diameters of less than 20 .ANG. units, CO.sub.2 /CH.sub.4 selectivity of at least 20 and CO.sub.2 permeability of at least 1.0 SCFH/ft.sup.2 at 100 p.s.i.

Abstract: A novel class of polyimides useful in making semipermeable membranes for gas separation is synthesized by the reaction of 4,4'-[hexafluoroisopropylidene]-bis-[phthalic anhydride] (6FDA) with 3,7-diamino-2,8-dimethyldiphenylenesulfone (AMPS). In lieu of the two methyl groups the diamine may be substituted by H or C.sub.2-4 alkyl. Membranes made from the polyimides have high permeability for CO.sub.2 from mixtures containing CO.sub.2 and other gases such as CH.sub.4 and have commercially acceptable selectivity.