1
Okan M Ekiner, Richard A Hayes, Phillip Manos: Novel multicomponent fluid separation membranes. E I du Pont de Nemours and Company, February 4, 1992: US05085676 (124 worldwide citation)

A process for preparing multicomponent gas separation membranes is disclosed. The process involves casting two or more solutions of polymer, and partially removing solvent from the side of the cast polymer that is to form the gas separation layer of the membrane. The membrane is then quenched to fre ...


2
Richard A Hayes: Polyimide gas separation membranes. E I Du Pont de Nemours and Company, January 5, 1988: US04717394 (113 worldwide citation)

Semi-flexible aromatic polyimides, prepared by polycondensation of dianhydrides with diamines having alkyl substituents on all ortho positions to the amine functions, or with mixtures of diamines, some components having substituents on all positions ortho to the amine functions, are disclosed. Membr ...


3
Richard A Hayes: Polyimide gas separation membranes. E I Du Pont de Nemours and Company, November 10, 1987: US04705540 (103 worldwide citation)

A highly permeable aromatic polyimide gas separation membrane and the process of using it are disclosed. The aromatic polyimide has the formula ##STR1## wherein --Ar-- is ##STR2## or mixtures thereof, --X, --X.sub.1, --X.sub.2 and --X.sub.3 independently are alkyl groups having 1 to 6 carbon atoms o ...


4
Richard A Hayes: Polyimide gas separation membranes. E I Du Pont de Nemours and Company, January 5, 1988: US04717393 (97 worldwide citation)

Semi-flexible aromatic polyimides, prepared by polycondensation of dianhydrides with phenylene diamines having alkyl substituents on all ortho positions to the amine functions incorporating at least in part 3,3',4,4'-benzophenone tetracarboxylic dianhydride, are auto photochemically crosslinkable. M ...


5
Richard A Hayes: Polyimide gas separation membranes. E I Du Pont de Nemours and Company, Frank C Hilberg Jr, November 14, 1989: US04880442 (45 worldwide citation)

Aromatic polyimide gas separation membranes containing the repeating unit: ##STR1## where --Ar-- =is ##STR2## or mixtures thereof, ##STR3## or mixtures thereof Where --X, X.sub.1, X.sub.2, and X.sub.3 are independently primary or secondary alkyl groups having 1 to 6 carbon atoms preferably methyl or ...


6
Richard A Hayes: Polyimide gas separation membranes. E I Du Pont De Nemours and Company, June 13, 1989: US04838900 (41 worldwide citation)

Aromatic polyimide gas separation membranes of the formula: ##STR1## or mixtures thereof, --R'--is ##STR2## linear alkylene groups of the formula (CH.sub.2).sub.1-3 or mixtures thereof, where --R" is ##STR3## are independently primary or secondary alkyl groups having 1 to 6 carbon atoms preferably m ...


7
Richard A Hayes: Amine-modified polyimide membranes. E I du Pont de Nemours and Company, January 1, 1991: US04981497 (39 worldwide citation)

Process of reacting polyimide membranes for separation of mixtures of fluids and particularly separation of mixtures of gas with primary or secondary mono-, di-, tri- or polyamines and the resultant products are disclosed. This modification results in improved gas permeation properties and, in some ...


8
Okan M Ekiner, Richard A Hayes: Phenylindane-containing polyimide gas separation membranes. E I Du Pont de Nemours and Company, Craig H Evans, May 14, 1991: US05015270 (29 worldwide citation)

A permselective polyimide membrane having phenylindane residues incorporated into the polyimide backbone chain exhibiting high selectivity while maintaining good gas permeation rates and a process for using.


9
Richard A Hayes: Copolyimide gas separation membranes derived from substituted phenylene diamines and substituted methylene dianilines. E I Du Pont de Nemours and Company, June 12, 1990: US04932982 (27 worldwide citation)

An aromatic copolyimide gas separation membrane and the process of using it to separate one or more gases from a mixture of gases are disclosed. The aromatic copolyimide is the condensation product of a aromatic tetracarboxylic dianhydride with a phenylene diamine and a methylene dianiline both of w ...


10
Okan M Ekiner, Richard A Hayes: Production of aromatic polyimide membranes. E I Du Pont de Nemours and Company, L Air Liquide, Craig H Evans, January 8, 1991: US04983191 (25 worldwide citation)

A process of producing a polyimide gas separation membranes comprising adding an oligomeric or polymeric aromatic epoxy resin to the dope solution, the resin being soluble in the polyimide or polyamic acid precursor, the solvent and the final membrane and the membrane comprising a blend of the polyi ...