Patents by Inventor David Karl Schisla

David Karl Schisla 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: 6262145
    Abstract: A method for extracting and separating extractive components from fluids is provided. A first fluid and an extraction fluid are added to a vessel, thereby creating a two-phase two-layer system, wherein the first fluid and the extraction fluid are discrete and the two-phase system has a first fluid/extraction fluid interface. The two-phase system is then agitated, wherein the first fluid phase and the extraction fluid phase remain as substantially discrete layers. A means for communication between the first fluid and the extraction fluid is provided. The communication of the phases results in the extractive components being extracted from the first fluid into the extraction fluid. Agitation is stopped and the first fluid is recovered having reduced extractive components.
    Type: Grant
    Filed: December 15, 1999
    Date of Patent: July 17, 2001
    Assignee: Shell Oil Company
    Inventors: Rudolf Jacobus Winjngaarden, Ye-Mon Chen, David Karl Schisla
  • Patent number: 6228947
    Abstract: The present invention provides a process for making functionalized polymers comprising the steps of (a) initiating polymerization of an unsaturated monomer with a lithium initiator having the structure R1R2R3Si—O—A—Li wherein A is a branched or straight chain bridging group having at least two carbon atoms, R1,R2, and R3 are alkyl, alkoxy, aryl, or alkaryl groups having from 1 to 10 carbon atoms, thus producing a functionalized polymer which has a protecting silyl group at one end thereof; and (b) contacting the protected polymer with from 0.5 to 1.1 moles of aqueous fluoroboric acid per mole of polymer at 0 to 50° C. for 1 to 10 minutes, and (c) contacting the resulting solution with water, and (d) recovering a linear or branched deprotected polymer having one or more terminal functional groups.
    Type: Grant
    Filed: January 24, 2000
    Date of Patent: May 8, 2001
    Assignee: Shell Oil Company
    Inventor: David Karl Schisla
  • Patent number: 6217798
    Abstract: This invention is a process for making a difunctional lithium initiator which comprises reacting a secondary or tertiary lithium alkyl with a diisopropenylbenzene compound in the presence of diethyl ether at a temperature of 25 to 50° C. wherein the molar ratio of the diethyl ether to the lithium alkyl is from above 0.1:1 to 2:1 and the diisopropenylbenzene compound and the diethyl ether are first mixed together and then added to the lithium alkyl. The molar ratio of the diisopropenylbenzene compound to the lithium alkyl should be as close to 0.5:1 as possible. An excess of lithium alkyl may be used if a product containing both diinitiator and monoinitiator is preferred. It is preferred that the molar ratio of diethyl ether to lithium alkyl be as close to 1:1 as possible.
    Type: Grant
    Filed: September 30, 1999
    Date of Patent: April 17, 2001
    Assignee: Shell Oil Company
    Inventors: Carl Lesley Willis, Grant Wesley Haddix, David Karl Schisla, Fred Hendrik van der Steen
  • Patent number: 6184307
    Abstract: This invention is a method for producing butadiene-isoprene block copolymers with a specified amount of residual unsaturation in the polyisoprene blocks utilizing a hydrogenation catalyst wherein the hydrogenation residence time is minimized.
    Type: Grant
    Filed: January 20, 1999
    Date of Patent: February 6, 2001
    Assignee: Shell Oil Company
    Inventor: David Karl Schisla
  • Patent number: 6103846
    Abstract: The preparation of di- or polyfunctional polymers by anionic polymerization using functionalized initiators having the structure R.sup.1 R.sup.2 R.sup.3 Si--A--B, wherein each R is methyl and A is a hydrocarbon bridging group containing from 1 to 25 carbon atoms, and B is an alkali metal, is improved when polymerization occurs in the presence of a polymerization termination inhibitor which is a metal alkyl which has been added at a concentration to afford a molar ratio of the termination inhibitor to living polymer chain ends of about 0.1:1 to about 10:1.
    Type: Grant
    Filed: May 5, 1999
    Date of Patent: August 15, 2000
    Assignee: Shell Oil Company
    Inventors: Carl Lesley Willis, Robert Charles Bening, Michael Wayne Potter, Grant Wesley Haddix, David Karl Schisla, Thomas Carl Semple, Daniel Earl Goodwin
  • Patent number: 6043299
    Abstract: A method for extracting and separating extractive components from fluids is provided. A first fluid and an extraction fluid are added to a vessel, thereby creating a two-phase two-layer system, wherein the first fluid and the extraction fluid are discrete and the two-phase system has a first fluid/extraction fluid interface. The two-phase system is then agitated, wherein the first fluid phase and the extraction fluid phase remain as substantially discrete layers. A means for communication between the first fluid and the extraction fluid is provided. The communication of the phases results in the extractive components being extracted from the first fluid into the extraction fluid. Agitation is stopped and the first fluid is recovered having reduced extractive components.
    Type: Grant
    Filed: October 15, 1997
    Date of Patent: March 28, 2000
    Assignee: Shell Oil Company
    Inventors: Rudolf Jacobus Wijngaarden, Ye-Mon Chen, David Karl Schisla
  • Patent number: H1956
    Abstract: In a process for producing hydrogenated block copolymers of conjugated dienes and/or vinyl aromatic hydrocarbons which comprises anionically polymerizing the monomers in an inert hydrocarbon solvent in the presence of an alkali metal initiator whereby a polymer cement is produced, contacting the cement with hydrogen under hydrogenation conditions in the presence of a hydrogenation catalyst, and then removing the hydrogenation catalyst residue by washing the polymer cement with water or an aqueous acid, the improvement which comprises reducing the viscosity of the polymer cement by polymerizing the block copolymer under conditions such that the vinyl content of the polymer produced in the polymerization step is in the range from 45 to 80 percent by weight.
    Type: Grant
    Filed: June 8, 1998
    Date of Patent: April 3, 2001
    Assignee: Shell Oil Company
    Inventors: David Karl Schisla, Michael John Modic, Eleanor Meyer de Groot