Patents by Inventor Paul Wittmer

Paul Wittmer 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).

  • Particulate polystyrene containing blowing agent and having improved expandability
    Patent number: 4525484
    Abstract: Particulate polystyrene containing blowing agent and having improved expandability is based on polystyrene having a weight-average mean molecular weight of not more than from 130,000 to 180,000 and a molecular weight distribution curve in which the high molecular weight flank drops steeply. The expandable polystyrene particles are produced by polymerizing styrene in aqueous suspension in the presence of blowing agents and of chain transfer agents or styrene oligomers.
    Type: Grant
    Filed: June 21, 1984
    Date of Patent: June 25, 1985
    Assignee: BASF Aktiengesellschaft
    Inventors: Klaus Hahn, Paul Wittmer, Isidoor De Grave, Rupert Schick, Adolf Echte
  • Particulate polystyrene containing blowing agent and having improved expandability
    Patent number: 4520135
    Abstract: Particulate polystyrene containing blowing agent and having improved expandability is based on polystyrene having a weight-average mean molecular weight of not more than from 130,000 to 180,000 and a molecular weight distribution curve in which the high molecular weight flank drops steeply. The expandable polystyrene particles are produced by polymerizing styrene in aqueous suspension in the presence of blowing agents and of chain transfer agents or styrene oligomers.
    Type: Grant
    Filed: September 13, 1983
    Date of Patent: May 28, 1985
    Assignee: BASF Aktiengesellschaft
    Inventors: Klaus Hahn, Paul Wittmer, Isidoor De Grave, Rupert Schick, Adolf Echte
  • Particulate polystyrene containing blowing agent and having improved expandability
    Patent number: 4513105
    Abstract: Particulate polystyrene containing blowing agent and having improved expandability is based on polystyrene having a weight-average mean molecular weight of not more than from 130,000 to 180,000 and a molecular weight distribution curve in which the high molecular weight flank drops steeply. The expandable polystyrene particles are produced by polymerizing styrene in aqueous suspension in the presence of blowing agents and of chain transfer agents or styrene oligomers.
    Type: Grant
    Filed: June 21, 1984
    Date of Patent: April 23, 1985
    Assignee: BASF Aktiengesellschaft
    Inventors: Klaus Hahn, Paul Wittmer, Isidoor De Grave, Rupert Schick, Adolf Echte