Air Products and Chemicals, Inc.

Langsam, Michael

Lescher Savoca, Ann C.

Savoca, Ann C. L.

Michael Langsam

William F Burgoyne, Jr

Lloyd Mahlon Robeson

Michael E Ford

Jeremiah P Casey

Ann C Savoca

Ingrid Kristine Meier

Mark Leonard O'Neill

William Franklin Burgoyne, Jr

Madhu Anand

Pushpinder S Puri

Richard Henry Bott

Chao-fong Tien

Robert L Fowlkes

Daniel V Laciak

Andrew D Surnamer

John Tze-Chiang Cheng

Ann C Lescher Savoca

Nanoporous polymer films for extreme low and interlayer dielectrics

Regiospecific polyamide-imides are cast to form membranes which exhibit superior gas separation properties when compared to polyamide-imide membranes formed from random copolymers. The regiospecific polyamide-imides are synthesized by reacting specific aromatic diimide dicarboxylic acids with select aromatic diamines.

Gas separation membranes based on regiospecific polyamide-imides

The present invention is a class of semi-permeable polymeric membranes and processes for using such membranes to separate one or more components of a gas mixture. The membranes which are formed from a polymer blend of a first polyimide containing an aromatic diamine and a second polyimide containing an alkenylated diamine having an allyl or allylaryl group exhibit high gas perm-selectivities. The polyimide blends can be surface modified by treatment with an activating force such as high energy electromagnetic irradiation or with a free radical source to impart enhanced selectivity to the membrane without causing a large decrease in composite permeance. These membranes formed from polyimide blends are especially useful in effecting the separation of oxygen and nitrogen from air.

Gas separating membranes formed from blends of polyimide polymers

Diamine compounds having the structural formula: ##STR1## wherein R.sub.1 is a methyl or ethyl group, can be used in preparing various polymers which are useful components in gas separation membranes. The combined effect of specific substituents ortho to the amino groups and the fluorenylidene bridging group imparts useful properties to polymeric membranes formed with these monomers.

Ortho-alkylated bisanilines having fluorenylidene bridging groups

The present invention is a class of semi-permeable polyimide membranes and a process for using such membranes to separate one or more components of a gaseous mixture. The membranes are prepared from a polyimide having surface-modifiable functionalities comprising repeating units formed from an aromatic dianhydride and a bridged alkylated bisaniline wherein the bridging group of the diamine possesses restricted, rotatable rigid or low Van Der Waal energy substituents which are orthogonal to the polymer backbone. The membranes formed therefrom are contacted in the presence of an oxygen source with an activating force such as high energy electromagnetic irradiation to effect modification of the polymer surface. The surface-modified polyimide membranes exhibit high gas perm-selectivities and are especially useful in effecting the separation of oxygen and nitrogen from air.

Gas separating membranes from polyimide polymers and a process for using

The present invention is a class of semi-permeable polyimide membranes and a process for using such membranes to separate one or more components of a gaseous mixture. The membranes are prepared from a polyimide having surface-modifiable functionalities comprising repeating units formed from an aromatic dianhydride and an alkyl-substituted phenylenediamine having at least one hydrogen atom located on a ring position ortho to an amine nitrogen. The membranes formed therefrom are contacted in the presence of an oxygen source with an activating force such as high energy electromagnetic irradiation to effect modification of the polymer surface. The surface-modified polyimide membranes exhibit high gas perm-selectivities and are especially useful in effecting the separation of oxygen and nitrogen from air.

Gas separating membranes from polyimide polymers

The present invention is a class of polymeric membranes formed from aromatic polyamides derived from dicarboxylic acid chlorides and cardo diamines having alkyl substituents on all portions ortho to the amine functions. These polyamide membranes exhibit high gas permselectivities and are useful in various gas separation applications.

Membranes formed from rigid aromatic polyamides

Diamine compounds having the structural formula: ##STR1## wherein R.sup.1 and R.sup.2 are independently methyl, ethyl or isopropyl groups, can be used in preparing various polymers which are useful in gas separation membranes. The combined effect of alkyl substituents ortho to the amino groups along with the specific bridging group imparts useful properties to polymeric membranes formed with these diamines.

Alkylated 1,1-bis(4-aminophenyl)-1-phenyl-2,2,2-trifluoroethanes

Water or gas containing organic impurities is purified by contact with a poly(trialkylsilylpropyne), such as poly[1-(trimethylsilyl)-1-propyne], operating as a bulk absorbent. Regeneration of the absorbent can be by vacuum or a stream of air.

Water or gas purification by bulk absorption

The present invention is a class of polyimide membranes wherein the diamine portion of the polymer structure is formed from 2,5-di-t-butyl-1,4-phenylenediamine. Membranes formed from polyimides containing this diamine structure exhibit unexpectedly high gas permeability properties and are especially useful for separating oxygen from nitrogen or air.

Polyimide membranes and their use for gas separation

The present invention is a class of polyimide membranes containing copolymerizable, surface modifiable units containing both aromatic diamines and alkenylated diamines having an allyl or allylaryl group preferably positoned ortho to an amine functionality. The polyimide membranes can be surface modified by treatment with an activating force such as high energy electromagnetic irradiation or with a free radical source to impart high selectivity to the membrane without causing a large decrease in composite permeance.

Membranes formed from unsaturated polyimides

The present invention is a class of polyimide membranes containing copolymerizable, surface modifiable units containing both aromatic diamines and alkenylated diamines having a vinyl or vinylaryl group preferably positioned ortho to an amine functionality. The polyimide membranes can be crosslinked by treatment with an activating force such as high energy electromagnetic irradiation or with a free radical source to impart high selectivity to the membrane without causing a large decrease in composite permeance.

Polymeric trisubstituted silylalkynes useful for forming gas separation membranes are prepared at accelerated polymerization rates and with improved yields in the presence of a Group VV or VIB Metal halide catalyst such as TaCl.sub.5, by employing about 0.1 to 5 mole %, based upon total alkyne concentration, of a trialkylgermylalkyne compound.

Process for the polymerization tri-substituted silylalkynes

The present invention is a class of polyimide membranes wherein the diamine portion of the polymer structure is an alkylated bisaniline. The bridging group of the diamine possesses restricted, rotatable rigid, or low Van Der Waal energy substituents which are orthogonal to the polymer backbone. These polyamide membranes exhibit enhanced gas flux and are useful in various gas separation applications.

Polyimide membrane having improved flux

The present invention is a modified polymeric membrane having improved selectivity for separating gas mixtures. The membrane comprises a silyl substituted polyacetylene polymer to which has been added 5 to 50 wt. % of an additive which is miscible with the polymer, has a boiling point &gt;300.degree. C. at atmospheric pressure, is soluble in a common solvent for the polymer and increases the selectivity ratio of O.sub.2 /N.sub.2 by at least 15% over the polymer without the additive.

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Allentown, PA, United States of America

Michael Langsam