Michael Langsam, 68Allentown, PA

4835229, May 30, 1989

Apr 29, 1988

7/187803

Michael Langsam - Allentown PA

Air Products and Chemicals, Inc. - Allentown PA

C08F 420
C08F 422

526147

Polymeric tri-substituted silylalkynes useful for forming gas separation membranes are prepared at accelerated polymerization rates and increased molecular weights by employing at polymerization temperatures a binary catalyst system of Group VB or VIB metal halide such as TaCl. sub. 5 and a tertiary amine compound such as pyridine in an aromatic solvent.

4859215, Aug 22, 1989

May 2, 1988

7/144295

Michael Langsam - Allentown PA
Pushpinder S. Puri - Macungie PA
Madhu Anand - Allentown PA
Daniel V. Laciak - Fogelsville PA

Air Products and Chemicals, Inc. - Allentown PA

B01D 5322

55 16

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 >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.

4451625, May 29, 1984

Aug 5, 1982

6/405638

John T. C. Cheng - Allentown PA
Michael Langsam - Allentown PA

Air Products and Chemicals, Inc. - Allentown PA

C08F 220

526 62

This invention relates to a method for reducing the amount of wall fouling in the suspension polymerization of vinyl chloride. The surfaces of the polymerization reactor are wetted with a solution containing from 5 to 50 wt % alkali metal hydroxide, 0. 01 to 1 wt % free radical inhibitor and 0. 01 to 1 wt % surface active agent prior to charging the vinyl chloride polymerization recipe to the reactor. Preferably, the surface of the wetted reactor is heated to a temperature from 40. degree. to 100. degree. C. for at least 5 minutes prior to charging the polymerization recipe.

4897092, Jan 30, 1990

Feb 27, 1989

7/316214

William F. Burgoyne - Emmaus PA
Michael Langsam - Allentown PA

Air Products and Chemicals, Inc. - Allentown PA

B01D 5322

55 16

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.

4931182, Jun 5, 1990

Nov 8, 1989

7/433495

William F. Burgoyne - Emmaus PA
Michael Langsam - Allentown PA
Michael E. Ford - Coopersburg PA
Jeremiah P. Casey - Emmaus PA

Air Products and Chemicals, Inc. - Allentown PA

B01D 1300

21050039

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.

5042993, Aug 27, 1991

Jul 24, 1990

7/557271

Ingrid K. Meier - Easton PA
Michael Langsam - Allentown PA

Air Products and Chemicals, Inc. - Allentown PA

B01D 5322
B01D 7164

55 16

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.

5055616, Oct 8, 1991

Jan 29, 1990

7/472001

William F. Burgoyne - Emmaus PA
Michael Langsam - Allentown PA

Air Products and Chemicals, Inc. - Allentown PA

C09B 1102
B01D 5322

564322

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.

4954144, Sep 4, 1990

Sep 12, 1989

7/406225

William F. Burgoyne - Emmaus PA
Michael Langsam - Allentown PA
Robert L. Fowlkes - Milton FL

Air Products and Chemicals, Inc. - Allentown PA

B01D 5322
B01D 7164

55 16

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.