Patents by Inventor Steven L. Fenske

Steven L. Fenske 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).

  • Patent number: 4681929
    Abstract: A process for extracting resin and rubber from guayule plants utilizing a portion of recycled miscella and a fresh solvent system. An expression step is applied to the plants to enhance recovery of resin and rubber extract. The solvent system is preferably an organic polar solvent and a hydrocarbon solvent for rubber for simultaneous resin and rubber extraction containing at least 50% by weight of the hydrocarbon solvent. The process can be a one-step method wherein resin and rubber are generally simultaneously extracted.
    Type: Grant
    Filed: April 29, 1985
    Date of Patent: July 21, 1987
    Assignee: The Firestone Tire & Rubber Company
    Inventors: William M. Cole, Steven L. Fenske, David J. Serbin, Shrikant R. Malani, Frank J. Clark, Joanne L. Beattie
  • Patent number: 4327064
    Abstract: Substantially linear polydichlorophosphazene polymers having a degree of polymerization of from 20 to 50,000 are prepared by an improved solution polymerization process which involves the polymerization of substantially pure cyclic dichlorophosphazene oligomers represented by the formula (NPC1.sub.2).sub.n, in which n is from 3 to 7, in cycloaliphatic solvents in the presence of a boron trihalide catalyst or a complex of a boron trihalide with an oxygenated phosphorus compound.The process provides for the production of substantially gel free linear polydichlorophosphazene polymer, improved polymerization rates and easier handling of the polymerizate for subsequent derivatization reactions.
    Type: Grant
    Filed: August 4, 1980
    Date of Patent: April 27, 1982
    Assignee: The Firestone Tire & Rubber Company
    Inventors: John W. Fieldhouse, Steven L. Fenske
  • Patent number: 4129529
    Abstract: The production of phosphazene polymers represented by the general formula ##STR1## WHEREIN N IS AN INTEGER FROM 7 TO UPWARDS OF 50,000 WHEREIN ONE OR MORE KINDS OF OR or OR' groups is attached to the phosphorus atoms in a substantially linear chain of alternating P and N atoms, the groups when more than one group is present being randomly distributed along the PN backbone, is enhanced by employing a single solvent for both each of the reactants (polydihalophosphazene and either aryloxide and/or alkoxide) and for the product (phosphazene polymer). By this expedient, the formation of the desired product is achieved in a homogeneous system rather than in a heterogeneous system as in the prior art where different solvents were employed for each of the reactants and for the reaction products.
    Type: Grant
    Filed: August 12, 1977
    Date of Patent: December 12, 1978
    Assignee: The Firestone Tire & Rubber Company
    Inventors: John W. Fieldhouse, Daniel F. Graves, William M. Cole, Mark L. Stayer, Steven L. Fenske
  • Patent number: 4128710
    Abstract: The production of phosphazene polymers represented by the general formula ##STR1## WHEREIN R and R' are organic radicals hereinafter defined, and wherein n is an integer from 20 to upwards of 50,000 wherein one or more kinds of OR or OR' groups is attached to the phosphorus atoms in a substantially linear chain of alternating P and N atoms, the groups when more than one group is present being randomly distributed along the PN backbone, as described in copending United States Patent Application Ser. No. 824,004 filed Aug. 12, 1977, is enhanced by an improved procedure for the separation of the sodium chloride by-product from the derivatized phosphazene polymer. By treating the reaction mixture with carbon dioxide, in the presence of water and preferably with an additional alkali metal salt, agglomeration of the sodium chloride is accomplished, and a clean separation of the NaCl from the polyphosphazene ester is more readily achieved.
    Type: Grant
    Filed: October 25, 1977
    Date of Patent: December 5, 1978
    Assignee: The Firestone Tire & Rubber Company
    Inventors: John W. Fieldhouse, Daniel F. Graves, William M. Cole, Mark L. Stayer, Steven L. Fenske