The Dow Chemical Company

Charles W Martin

Nobuyuki Ishibe

Roscoe L Pearce

Eldon L Ward

Tien K Tran

Terry D Gordon

Melisa Davila

Stan H Baker

Bobby R Ezzell

John W Bozzelli

Terrence L Caskey

John D Weaver

Marinda L Wu

H Hunter Paalman

George D Shier

Robert E Aikman, Jr

John N Zabasajja

Leroy S Krawczyk

John P McGraw

Robert DeVellis

Curtis M Tong

Lawrence R Schroeder

Paul R Peters

John W Gross, Sr

Non-evaporative processes for coating ion-containing polymers onto selected substrates and the articles made thereby, which processes fundamentally comprise contacting a substrate with a dispersion or solution of an ion-containing polymer and especially a solventless dispersion of a perfluorosulfonic acid ionomer, and thereafter contacting the dispersion- or solution-wetted substrate with a solution of a salt or of a strongly ionizing acid of a sufficient concentration to cause an adherent coating of the ion-containing polymer to be formed on the substrate.

Processes for forming thin, durable coatings of cation-containing

A novel, improved process for forming a thin, adherent coating of a perfluorocarbon ionomer on a polymeric substrate which is typically in powdered form, fibrous form, or a mixture of powdered and fibrous forms, from a colloidal dispersion of the perfluorocarbon ionomer in a liquid medium which consists essentially of water and is substantially free of organic solvents, comprising adding a) the colloidal dispersion and b) a salt or a strongly ionizing acid to a vessel containing the polymeric substrate, and subjecting the dispersion, salt or acid and polymeric material to high shear conditions whereby a thin, durable coating of the perfluorocarbon ionomer is formed on the polymeric substrate.

Solventless process for forming thin, durable coatings of

A bonded, non-asbestos chlor-alkali diaphragm comprising one or more water-wettable materials and one or more chemically-resistant materials, which is characterized by having a Macmullin number and average diaphragm thickness such that the product of these is between about 5 and about 30 millimeters when the average diaphragm thickness is measured in millimeters, and by a median pore size between about 0.1 microns and about 1 micron, wherein one or more of the chemically-resistant materials is or are coated with a durable, adherent coating of an ion-containing polymer which is bonded into the diaphragm on such materials.

Non-asbestos diaphragm separator

Process for preparing haloperfluoro and perfluoro ethers wherein a metal halide is reacted with a 3-haloperfluoropropene oxide to obtain a 2,3-dihaloperfluorocarbonyl fluoride; a metal halide, 2,3-dihaloperfluorocarbonyl fluoride and 3-haloperfluoropropene oxide are reacted to obtain a 2-(2',3'-dihaloperfluoropropoxy)-3-haloperfluoropropionyl fluoride; 2-(2',3'-dihaloperfluoropropoxy)-3-haloperfluoropropionyl fluoride is decarboxylated and dehalogenated to obtain perfluorovinylallylether. Alternatively, 2-(2',3'-dihaloperfluoropropoxy)-3-haloperfluoropropionyl fluoride is reacted with metal halide and 3-haloperfluoropropene oxide to obtain a 2-[2'-(2',3'-dihaloperfluoropropoxy)-3'-haloperfluoropropoxy]-3-haloperflu oropropionyl fluoride, or a higher polyether, and 2-[2'-(2',3'-dihaloperfluoropropoxy)-3'-haloperfluoropropoxy]-3-haloperflu oropropionyl fluoride or the polyether is decarboxylated and dehalogenated to obtain a 3,6-dioxa-5-halodifluoromethylperfluoronona-1,8-diene or the corresponding polyether.

Preparation of haloperfluoro and perfluoro ethers

Homolymers prepared from diunsaturated mono- or poly- haloperfluoro or perfluoro ethers, and copolymers prepared from two or more of such ethers, or one or more of such ethers and one or more other ethylenically unsaturated monomers; and articles fabricated from such polymers.

Polymers of haloperfluoro and perfluoro ethers

The invention is a method for separating one or more polar liquids from one or more non-polar liquids which comprises the following steps. First, contacting a mixture comprising one or more polar liquids and one or more non-polar liquids with one side of a membrane comprising a polymer of a perfluorosulfonic acid, or metal salt thereof, which is adapted for selective permeation of the polar liquids over the non-polar liquids under conditions such that the polar liquids selectively permeate through the membrane. Second, passing a desiccant fluid by, pulling a vacuum on, or a combination thereof, the other side of the membrane, under conditions such that the polar liquids which have permeated through the membrane are carried away from the membrane. Third, removing the fluid desiccant containing the permeated polar liquids or the permeated polar liquids wherein a vacuum is used, from the vicinity of the membrane. Fourth, removing the non-polar liquids from the vicinity of the membrane. Another aspect of this invention is a novel hollow fiber membrane device useful for performing a preferred mode of the above-described method. This method allows the removal of one or more polar liquids which are dissolved in or entrained in one or more non-polar liquids in a continuous manner which no shoft-term changeout required.

Method and device for separating polar from non-polar liquids using

The invention relates to a process of separating gases using a membrane fabricated from a polymer containing a perfluorinated backbone and pendant hydrated metal ionomer groups wherein the pendant hydrated metal ionomer groups contain cations of alkali metals, alkaline earth metals, or transition metals bound to SO.sub.3.sup.-. The hydrated membranes have improved gas permeabilities with comparable gas selectivities over the unhydrated membranes. The membranes may be used to separate gas mixtures containing such gases as carbon dioxide and methane.

Hydrated metal ionomer membranes for gas separation

This invention discloses improved heterogeneous acid catalysts and a method for preparing these catalysts. A heterogeneous acid catalyst has been prepared by treating a carrier material with a solution containing a fluorocarbonsulfonic acid polymer dissolved in a suitable solvent, removing the solvent, and heat treating the coated carrier in such a way so as to prevent the polymer from being leached off the carrier. The final heat treatment of the composition to prevent the polymer from redissolving comprises an improvement in the preparation of a heterogeneous catalyst.

Method for depositing a fluorocarbonsulfonic acid polymer on a support

The corrosion of ferrous metal surfaces in gas conditioning apparatus is inhibited by using a gas conditioning solution such as aqueous alkanolamines which contain thionitrogen compounds such as metal thiocyanates or thioamides. After recycling the gas conditioning solution for a few days, the solution dissolves sufficient amounts of nickel or cobalt or other metals in the equipment to act as a synergist with the thionitrogen compounds. In the event, the equipment does not contain any soluble synergistic metals, these metals may be added to the gas conditioning solution as soluble metal salts. Examples of useful additive metals are cobalt, nickel, calcium, copper, chromium, zinc, tin, aluminum, and magnesium.

Inhibitors for acid gas conditioning solutions

Sour industrial gases containing carbon dioxide and hydrogen sulfide are treated with amines to remove the CO.sub.2 and H.sub.2 S. The amine absorbent containing or loaded with H.sub.2 S and CO.sub.2 is regenerated and the off-gas containing concentrated amounts of H.sub.2 S and CO.sub.2 is treated in a second amine absorber to produce an amine absorbent loaded with H.sub.2 S. This amine is then regenerated to provide an off-gas containing a high ratio of H.sub.2 S to CO.sub.2 which makes it suitable for use as the feed gas to a sulfur recovery unit such as a Claus plant. The process is automatically controlled so that the concentration of H.sub.2 S in the second amine absorber is built up to and controlled at a desired set point so that the off-gas has the required H.sub.2 S/CO.sub.2 ratio.

Process for removing H.sub.2 S from sour gases with generation of a

Novel bis(dithiocarbamate) salts, the mixed transition metal salts, and zinc salt amine complexes thereof are claimed. These novel compounds have utility as antifungal agents.

(Bis)dithiocarbamate) salts

Bis(dithiocarbamate) salts

Polyglycolamines such as aminated polypropylene or polybutylene glycols and amine-initiated polypropylene and polybutylene glycols such as oxypropylated or oxybutylated lower alkanolamines inhibit the corrosion of ferrous metals by a nonoxidizing acid such as hydrochloric acid. Polyglycolamines of this class having an average molecular weight in the appropriate range of 300-5000 are effective inhibitors in 5-15 percent hydrochloric acid at moderately elevated temperatures.

Growing community of inventors

Lake Jackson, TX, United States of America

Charles W Martin