The Dow Chemical Company

Edgar S Sanders, Jr

Henry N Beck

Daniel O Clark

Theodore L Parker

John A Jensvold

Frederick L Coan

John D Summers

G Glenn Lipscomb, Ii

Jerry E White

David J Brennan

William E Mickols

Thomas O Jeanes

Hawk S Wan

Peter K Kim

Wudneh Admassu

Dana C Overman, Iii

Raymond W Mah

Susie K Landes

Jo N Anand

Prakash U Bakhru

A storage tank for compressed natural gas (CNG) comprises a hydroxy-phenoxyether polymermethane barrier liner and a fiber composite outer shell. The hydroxy-phenoxyether polymer has a methane transmission rate of not more than about 50 cc-mil/100 in.sup.2 -day (19.5 cm.sup.3 -mm/m.sup.2 -atm-day) at 25.degree. C. and 2000 psi (13,800 kPa) methane pressure.

Storage tanks for compressed natural gas with a hydroxy-phenoxyether

This invention relates to novel poly(arylene ether ketimine) gas separation membranes and a process for separating gases using such membranes.

Poly(arylene ether ketimine) gas separation membranes

The invention releates to semi-permeable gas separation membranes derived from oligomers containing reactive end groups.

Semi-permeable membranes derived from reactive oligomers

The invention relates to novel meta, parabisphenol based condensation uncross-linked polymer membranes and a method of separating gases using such membranes.

Meta, para-bisphenol based polymer gas separation membranes

The invention relates to novel aryl carbonate cyanoaryl ether gas separation membranes and a method of separating gases using such membranes.

Novel aryl carbonate cyanoaryl ether gas separation membranes

The invention relates to novel benzotrifluoride aryl ether membranes and a process for separating gases using such membranes.

Novel benzotrifluoride aryl ether gas separation membranes

The invention is a process for separating hydrogen from gas mixtures using a semi-permeable membrane consisting predominantly of polycarbonates derived from tetrahalobisphenols such as tetrabromobisphenol.

Process for separating hydrogen from gas mixtures using a semi-permeable

This invention relates to novel polyimide gas separation membranes derived from alicyclic dianhydrides and aliphatic, alicyclic, or aromatic diamines, and a process for using such membranes.

Novel alicyclic polyimide gas separation membranes

A process for the preparation of a membrane comprising bisphenol-based polycabonate wherein at least 25 percent by weight of the bisphenol moieties are tetrahalogenated wherein the halogen is Cl or Br, and the membrane prepared by such process. The process generally comprises: forming a mixture comprising (i) a bisphenol-based polycarbonate wherein at least 25 percent by weight of the bisphenol moieties are tetrahalogeneated, wherein the halogen is Cl or Br, and (ii) a solvent for such polycarbonate, wherein the mixture has a sufficient viscosity to allow extrusion at temperatures at which the mixture is homogeneous; heating the mixture to a temperature at which the mixture is a homogeneous fluid and extrudable, extruding the heated mixture into a shape suitable for membrane use; passing the formed membrane through a quench zone wherein the mixture undergoes phase separation, and the major portion of the solvent is removed from the formed membrane; wherein the membrane formed is a membrane with a discriminating region capable of separating oxygen from nitrogen. Such membranes have excellent mechanical and thermal properties.

Process for preparing membranes from tetrahalobisphenol polycarbonates

The invention is a composition useful for the preparation of POWADIR membranes of a bisphenol-based polycarbonate wherein at least 25 percent by weight of the bisphenol moieties are tetrahalogenated, wherein the halogen is Cl or Br, the composition comprising (i) a bisphenol-based polycarbonate wherein at least 25 percent by weight of the bisphenol moieties are tetrahalogenated, wherein the halogen is Cl or Br, (ii) a solvent for such polycarbonate, and (iii) a non-solvent for such polycarbonate. The composition is useful for extruding membranes wherein the membranes formed are POWADIR membranes with a discriminating region capable of separating oxygen from nitrogen. The composition of this invention allows the formation of membranes with excellent physical properties, good separation factors for oxygen and nitrogen, with excellent fluxes.

Composition useful in process for preparing powadir membranes from

The invention is a semi-permeable hollow fiber gas separation membrane possessing a non-external discriminating region fabricated from hydrophobic polymeric materials possessing less than about 1 weight percent equilibrium water content at about 25.degree. C. The invention includes a process for making such membranes as well as a method of using such membranes.

Semi-permeable hollow fiber gas separation membranes possessing a

The invention is a semi-permeable membrane which comprises a polymeric matrix with two porous surfaces and a region which functions to separate one or more gases from one or more other gases. The membranes of this invention exhibit excellent separation factors and flux. Such membranes are less prone to being damaged due to handling and exposure to contaminants due to the internal region which affects the separation, as the porous surfaces function to protect such region.

Semi-permeable membranes with an internal discriminating region

The invention is a process for the preparation of a POWADIR membrane comprising bisphenol-based polycarbonates wherein at least 25 percent by weight of the bisphenol moieties are tetrahalogenated wherein the halogen is Cl or Br, and the membrane prepared by such process. The process generally comprises: forming a mixture comprising (i) a bisphenol-based polycarbonate wherein at least 25 percent by weight of the bisphenol moieties are tetrahalogenated, wherein the halogen is Cl or Br, (ii) a solvent for such polycarbonate, and (iii) a non-solvent for such polycarbonate, wherein the mixture has a sufficient viscosity to allow extrusion at temperatures at which the mixture is homogeneous; heating the mixture to a temperature at which the mixture is a homogeneous fluid and extrudable; extruding the heated mixture into a shape suitable for membrane use; passing the formed membrane through a quench zone wherein the mixture undergoes phase separation, and the major portion of the solvent and non-solvent are removed from the formed membrane; wherein the membrane formed is a POWADIR membrane with a discriminating region capable of separating oxygen from nitrogen.

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Pittsburg, CA, United States of America

Edgar S Sanders, Jr