Patents by Inventor Hans-Dieter Speikamp

Hans-Dieter Speikamp 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 controlling the particle size in the preparation of expandable styrene polymers by suspension polymerization
    Patent number: 5189069
    Abstract: Expandable styrene polymer of controlled particle size is prepared by polymerizing styrene and optionally polymerizable comonomers in a stirred aqueous suspension in the presence of monomer-soluble free radical initiator and dispersant to the extent that at least 70%, based on the total monomer, of the monomers are polymerized in the aqueous suspension initially to a conversion of at least 70% by weight; and then adding the remaining monomer, initiator and optional copolymerizable monomer and additives to the polymerization medium over one to three hours.
    Type: Grant
    Filed: July 5, 1991
    Date of Patent: February 23, 1993
    Assignee: Huels Aktiengesellschaft
    Inventors: Hans-Dieter Speikamp, Adolf Kuhnle, Jurgen Bretschneider