Patents by Inventor Helmut L. Merten

Helmut L. Merten has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Process for producing N,N'-disubstituted paraphenylene diamine mixtures by sequential reductive alkylation
    Patent number: 4900868
    Abstract: Mixtures of N,N'-disubstituted paraphenylenediamines are produced in a process wherein a nitrogen-containing compound such as 4-nitrodiphenylamine is reductively alkylated with a plurality of ketones in sequence. Preferably, one ketone is reacted to completion with an excess of the nitrogen-containing compound, then an excess of a second ketone is added and the reaction is continued until the nitrogen-containing compound is consumed. The product is then separated from the volatiles and the unreacted portion of the second ketone is recovered.
    Type: Grant
    Filed: April 13, 1987
    Date of Patent: February 13, 1990
    Assignee: Monsanto Company
    Inventors: Helmut L. Merten, Leona M. Baclawski
  • Making nitrodiarylamines
    Patent number: 4614817
    Abstract: Nitrodiarylamines, useful as intermediates, are produced by combining a formyl derivative of an aromatic primary amine with a nitrohaloarene, at condensation temperature for forming nitrodiarylamine, and adding an alkoxide or cycloalkoxide of an alkali metal, excluding lithium.
    Type: Grant
    Filed: December 19, 1983
    Date of Patent: September 30, 1986
    Assignee: Monsanto Company
    Inventors: Otto W. Maender, Helmut L. Merten
  • Production of cyclohexylamine
    Patent number: 4384142
    Abstract: Cyclohexylamine is produced by the catalytic hydrogenation of aniline. In contact with a ruthenium catalyst and in the presence of from about one to about 8 parts by weight of ammonia, aniline is hydrogenated under an absolute pressure of from about 2 to about 5 MPa at a temperature of from about 160.degree. to about 180.degree. C. High yields and a minimum of byproducts result. The catalyst can be recycled.
    Type: Grant
    Filed: June 9, 1981
    Date of Patent: May 17, 1983
    Assignee: Monsanto Company
    Inventors: Helmut L. Merten, Gene R. Wilder
  • N,N'-Bis(1-cyclohexyl-1-ethyl)-p-phenylenediamine, and rubber compounds containing the same
    Patent number: 4297269
    Abstract: N,N'-Bis(1-cyclohexyl-1-ethyl)-p-phenylenediamine is disclosed as a novel compound, useful as an antidegradant for organic materials, such as rubber. Vulcanized or vulcanizable rubber compounds containing minor amounts of this compound show excellent resistance to ozone attack, under static or dynamic exposure.
    Type: Grant
    Filed: October 16, 1980
    Date of Patent: October 27, 1981
    Assignee: Monsanto Company
    Inventors: Helmut L. Merten, Gene R. Wilder
  • Stabilized amorphous calcium carbonate
    Patent number: 4237147
    Abstract: Stabilized amorphous calcium carbonate which is useful as a carbonate factor in effervescent compositions. Process for preparing stabilized amorphous calcium carbonate and compositions containing stabilized amorphous calcium carbonate.
    Type: Grant
    Filed: January 4, 1974
    Date of Patent: December 2, 1980
    Assignee: Monsanto Company
    Inventors: Helmut L. Merten, Gerald L. Bachman
  • Making nitrodiarylamines from formyl derivatives of aromatic amines and nitrohaloarenes by admixing with certain aqueous salt solutions
    Patent number: 4196146
    Abstract: Forming nitrodiarylamines by gradually admixing, at condensation temperature for forming a nitrodiarylamine, to a mixture of the formyl derivative of an aromatic amine and a nitrohalobenzene, eitherA. aqueous potassium carbonate, orB. aqueous potassium hydroxide and a member of the group consisting of potassium carbonate, tri-potassium phosphate, sodium tetraborate and potassium tetraborate and mixtures thereof, and concurrently removing water.
    Type: Grant
    Filed: March 13, 1978
    Date of Patent: April 1, 1980
    Assignee: Monsanto Company
    Inventors: Helmut L. Merten, Gene R. Wilder
  • Making a nitrodiarylamine by reacting an alkali metal salt of a formamide with a nitrohaloarene
    Patent number: 4187248
    Abstract: Preparation of a nitrodiarylamine from a nitrohaloarene and alkali metal salt of the formyl derivative of a primary aromatic amine is disclosed.
    Type: Grant
    Filed: November 23, 1977
    Date of Patent: February 5, 1980
    Assignee: Monsanto Company
    Inventors: Helmut L. Merten, Gene R. Wilder