The Dow Chemical Company

The D-H Titanium Company

David R Johnson

Norman G Moll

Paul R Juckniess

Kenneth J Stutts

Daniel A Batzel

Virginia A Hallfrisch

James E Anschutz

A method of making a semipermeable composite membrane comprising a discriminating layer formed insitu by interfacial polymerization is disclosed. The method provides for removal of a water immiscible solvent for a reactant in the interfacial polymerization by physical means not requiring a phase change such as a water knife, air knife, roller, or rubber blade. Composite membranes having good flux, good salt rejection, and low levels of remaining organic solvent are obtained.

Method of making thin film composite membranes

Expandable and expanded plastic materials having a majority of alkyl acrylate monomeric repeat units are disclosed. These materials when expanded have a volume expansion of at least 60 and maintain that volume expansion for a period of at least 30 minutes under expansion conditions after reaching the volume expansion of 60. Expandable and expanded plastic materials having a majority of alkyl acrylate monomeric repeat units and an inhibitor for the monomer(s) and a crosslinker incorporated into the plastic material upon monomer polymerization are also disclosed. Also disclosed are expandable and expanded plastic materials having a majority of alkyl acrylate monomeric repeat units with blowing agents of 2,2-dimethylbutane, 2,3-dimethylbutane or mixtures of one or both with 1-chloro-1,1-difluoroethane or mixtures of at least 30 percent of one or both with other volatile blowing agents. These specific types of formed patterns and core assemblies, wholly or partially formed from the destructible expanded closed-cell cellular plastic materials of the present invention have a decreased tendency to form nonvolatile residue during the casting of metals such as iron. Superior castings are thereby obtained without resort to uneconomic casting methods. Further disclosed is a method of casting metal castings using the disclosed expanded plastic material articles (Lost Foam or Evaporative Pattern Casting). The disclosed expanded plastic material articles are especially preferred for metal castings having a final carbon percentage of 1.8 weight pecent or less in the final casting.

Expandable and expanded plastic materials and methods for casting metal

Expandable and expanded plastic materials having a majority of alkyl acrylate monomeric repeat units are disclosed. These materials when expanded have a volume expansion of at least 60 and maintain that volume expansion for a period of at least 30 minutes under expansion conditions after reaching the volume expansion of 60. Expandable and expanded plastic materials having a majority of alkyl acrylate monomeric repeat units and an inhibitor for the monomer(s) and a crosslinker incorporated into the plastic material upon monomer polymerization are also disclosed. Also disclosed are expandable and expanded plastic materials having a majority of alkyl acrylate monomeric repeat units with blowing agents of 2,2-dimethylbutane, 2,3-dimethylbutane or mixtures of one or both with 1-chloro-1,1-difluoroethane or mixtures of at least 30 percent of one or both with other volatile blowing agents. These specific types of formed patterns and core assemblies, wholly or partially formed from the destructible expanded closed-cell cellular plastic materials of the present invention have a decreased tendency to form nonvolatile residue during the casting of metals such as iron. Superior castings are thereby obtained without resort to uneconomic casting methods. Further disclosed is a method of casting metal castings using the disclosed expanded plastic material articles (Lose Foam or Evaporative Pattern Casting). The disclosed expanded plastic material articles are especially preferred for metal castings having a final carbon percentatge of 1.8 weight percent or less in the final casting.

Expandable and expanded plastic materials having a majority of alkyl acrylate monomeric repeat units are disclosed. These materials when expanded have a volume expansion of at least 60 and maintain that volume expansion for a period of at least 30 minutes under expansion conditions after reaching the volume expansion of 60. Expandable and expanded plastic materials having a majority of alkyl acrylate monomeric repeat units and an inhibitor for the monomer(s) and a crosslinker incorporated into the plastic material upon monomer polymerization are also disclosed. Also disclosed are expandable and expanded plastic materials having majority of alkyl acrylate monomeric repeat units with blowing agents of 2,2-dimethylbutane, 2,3-dimethylbutane or mixtures of one or both with 1-chloro-1,1-difluoroethane or mixtures of at least 30 percent of one or both with other volatile blowing agents. These specific types of formed patterns and core assemblies, wholly or partially formed from the destructible expanded closed-cell cellular plastic materials of the present invention have a decreased tendency to form nonvolatile residue during the casting of metals such as iron. Superior castings are thereby obtained without resort to unecnomic casting methods. Further disclosed is a method of casting metal castings using the disclosed expanded plastic material articles (Lost Foam or Evaporative Pattern Casting). The disclosed expanded plastic material articles are especially preferred for metal castings having a final carbon percentage of 1.8 weight percent or less in the final casting.

Methods for preparing a formed cellular plastic material pattern

Expandable and expanded plastic materials having a majority of alkyl acrylate monomeric repeat units are disclosed. These materials when expanded have a volume expansion of at least 60 and maintain that volume expansion for a period of at least 30 minutes under expansion conditions after reaching the volume expansion of 60. Expandable and expanded plastic materials having a majority of alkyl acrylate monomeric repeat units and an inhibitor for the monomer(s) and a crosslinker incorporated into the plastic material upon monomer polymerization are also disclosed. Also disclosed are expandable and expanded plastic materials having a majority of alkyl acrylate monomeric repeat units with blowing agents of 2,2-dimethylbutane, 2,3-dimethylbutane or mixtures of one or both with 1-chloro-1,1-difluoroethane or mixtures of at least 30 percent of one or both with other volatile blowing agents. These specific types of formed patterns and core assemblies, wholly or partially formed from the destructible expanded closed-cell cellular plastic materials of the present invention have a decreased tendency to form nonvolatile residue during the casting of metals such as iron. Superior castings are thereby obtained without resort to uneconomic casting methods. Further disclosed is a method of casting metal castings using the disclosed expanded plastic material articles (Lost Form or Evaporative Pattern Casting). The disclosed expanded plastic material articles are especially preferred for metal castings having a final carbon percentage of 1.8 weight percent or less in the final casting.

Expandable and expanded plastic materials having a majority of alkyl acrylate monomeric repeat units are disclosed. These materials when expanded have a volume expansion of at least 60 and maintain that volume expansion for a period of at least 30 minutes under expansion conditions after reaching the volume expansion of 60. Expandable and expanded plastic materials having a majority of alkyl acrylate monomeric repeat units and an inhibitor for the monomer(s) and a crosslinker incorporated into the plastic material upon monomer polymerization are also disclosed. Also disclosed are expandable and expanded plastic materials having a majority of alkyl acrylate monomeric repeat units with blowing agents of 2,2-dimethylbutane, 2,3-dimethylbutane or mixtures of one or both with 1-chloro-1,1-difluoroethane or mixtures of at least 30 percent of one or both with other volatile blowing agents. These specific types of formed patterns and core assemblies, wholly or partially formed from the destructible expanded closed-cell cellular plastic materials of the present invention have a decreased tendency to form nonvolatile residue during the casting of metals such as iron. Superior castings are thereby obtained without resort to uneconomic casting methods. Further disclosed is a method of casting metal castings using the disclosed expanded plastic material articles (Lost Foam or Evaporative Pattern Casting). The disclosed expanded plastic material articles are especially preferred for metal castings having a final carbon percentage of 1.8 weight percent or less in the final casting.

Expandable beads and the like of thermoplastic organic polymer material, advantageously lightly-crosslinked in preparation, which are imbibed with halocarbon and/or light hydrocarbon (including mixed) blowing agents are advantageously tempered to provide excellent quality, uniformly fine-celled expanded cellular products therefrom by a quick quench from imbibition temperature to below 10 or so .degree. C. within one minute.

Uniform minimization of plastic foam cell size

Feed cathode for an electrolytic cell with a feed conduit suited to pass a metal compound therethrough from a source to an electrolyte in the cell. The feed cathode includes a member surrounding and substantially entirely enclosing at least an outlet of the conduit. The member is at least partially formed of an electrically conductive foraminous body suited to pass the electrolyte and ions of a multivalent metal compound therethrough. Preferably, the foraminous body has an electrical coefficient of greater than zero to about 1 and a flow coefficient of from about 0.1 to about 300.

Metal electrowinning feed cathode

An apparatus to electrolytically produce multivalent metals, such as titanium, from compounds thereof. The apparatus includes a suitable containing body with an anode and a cathode in compartments therein spaced apart by a foraminous diaphragm with at least a surface portion consisting essentially of nickel or, preferably, cobalt. The diaphragm has a diaphragm coefficient of greater than zero to about 0.5 when the coefficient of flow is about 0.1 to about 25. A multivalent metal compound feed means is combined with the cathode compartment to supply a multivalent metal compound to a molten salt electrolyte in the cathode compartment. The apparatus is sealed from the atmosphere to avoid contamination of the bath and metal product with certain atmospheric gases. Means of providing sufficient electrical and thermal energy to operate the cell are provided.

Apparatus for electrowinning multivalent metals

A method to electrolytically produce metallic titanium from compounds thereof. The method includes first inserting a foraminous diaphragm with at least a surface portion consisting essentially of nickel or, preferably, cobalt into an electrolytic cell. The diaphragm has a diaphragm coefficient of greater than zero to about 0.5 when the coefficient of flow is about 0.1 to about 25 in an electrolytic cell. The cell further includes an anode spaced apart by the diaphragm from a cathode and a titanium compound feed means. A feed means is combined with the cathode compartment to supply a titanium compound to a molten salt electrolyte in the cathode compartment. The apparatus is preferably sealed from the atmosphere to avoid contamination of the bath and metal product with certain atmospheric gases. An ionizable titanium compound is subsequently introduced into the electrolyte and an electromotive force impressed between the anode and the cathode to thereby deposit metallic titanium on the cathode.

Method of electrowinning titanium

A method to electrolytically produce metallic titanium from compounds thereof. The method includes first positioning a foraminous metallic diaphragm with a diaphragm coefficient of greater than zero to about 0.5 when the coefficient of flow is about 0.1 to about 25 in an electrolytic cell. The cell further includes an anode spaced apart from a cathode and a titanium compound feed means by the diaphragm. A feed means is combined with the cathode compartment to supply a titanium compound to a molten salt electrolyte in the cathode compartment. The apparatus is preferably sealed from the atmosphere to avoid contamination of the bath and metal product with certain atmospheric gases. An ionizable titanium compound is subsequently introduced into the electrolyte and an electromotive force impressed between the anode and the cathode to thereby deposite metallic titanium on the cathode.

An apparatus to electrolytically produce multivalent metals, such as titanium, from compounds thereof. The apparatus includes a suitable containing body with an anode and a cathode in compartments therein spaced apart by a foraminous metallic diaphragm. The diaphragm has a diaphragm coefficient of greater than zero to about 0.5 when the coefficient of flow is about 0.1 to about 25. A multivalent metal compound feed means is combined with the cathode compartment to supply a multivalent metal compound to a molten salt electrolyte in the cathode compartment. The apparatus is sealed from the atmosphere to avoid contamination of the bath and metal product with certain atmospheric gases. Means of providing sufficient electrical and thermal energy to operate the cell are provided.

Growing community of inventors

Midland, MI, United States of America

David R Johnson