Patents by Inventor Lee Spencer

Lee Spencer 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: 5798314
    Abstract: A supported catalyst component for an olefin polymerization catalyst consisting essentially of a solid particulate support and a magnesium halide; and an olefin polymerization catalyst consisting essentially of a solid particulate support and a magnesium halide, a Group 4 or 5 transition metal compound, and a Group 2 or 13 organometallic compound, and wherein a majority of particles of the solid particulate support are in the form of an agglomerate of subparticles.
    Type: Grant
    Filed: June 4, 1996
    Date of Patent: August 25, 1998
    Assignee: The Dow Chemical Company
    Inventors: Lee Spencer, Marc A. Springs
  • Patent number: 5688880
    Abstract: Metal complexes useful as olefin polymerization catalysts corresponding to the formula: ##STR1## wherein: L is a delocalized, .pi.-bonded group that is bound to M, containing up to 50 nonhydrogen atoms;M is a metal of Group 3, 4 or the Lanthanide series of the Periodic Table of the Elements;Z is a covalently bound, divalent substituent of up to 50 non-hydrogen atoms having the formula, --(ER.sub.2).sub.m --, wherein E independently each occurrence is carbon, silicon or germanium, R independently each occurrence is selected from the group consisting of C.sub.1-20 hydrocarbyl, and C.sub.1-20 hydrocarbyloxy, with the proviso that in at least one occurrence R is C.sub.
    Type: Grant
    Filed: December 11, 1995
    Date of Patent: November 18, 1997
    Assignee: The Dow Chemical Company
    Inventors: Lee Spencer, Peter N. Nickias
  • Patent number: 5661097
    Abstract: A supported catalyst component for an olefin polymerization catalyst comprising a solid particulate support, a magnesium halide, and optionally a Group 4 or 5 transition metal compound, a Group 2 or 13 organometal compound, and an electron donor, wherein a majority of particles of the solid particulate support is in the form of an agglomerate of subparticles. A process for preparing this supported catalyst component. A catalyst composition comprising this catalyst component and a cocatalyst. An olefin polymerization process using such a catalyst composition.
    Type: Grant
    Filed: August 12, 1994
    Date of Patent: August 26, 1997
    Assignee: The Dow Chemical Company
    Inventors: Lee Spencer, Marc A. Springs
  • Patent number: 5633419
    Abstract: A supported catalyst component for an olefin polymerization catalyst comprising a solid particulate support, a magnesium halide, and optionally a Group 4 or 5 transition metal compound, a Group 2 or 13 organometal compound, and an electron donor, wherein a majority of particles of the solid particulate support is in the form of an agglomerate of subparticles. A process for preparing this supported catalyst component. A catalyst composition comprising this catalyst component and a cocatalyst. An olefin polymerization process using such a catalyst composition.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: May 27, 1997
    Assignee: The Dow Chemical Company
    Inventors: Lee Spencer, Marc A. Springs
  • Patent number: 5487938
    Abstract: A transition metal containing catalyst useful for the polymerization of .alpha.-olefins is prepared by (A) forming in an inert atmosphere which excludes oxygen and moisture a slurry of (1) a porous inorganic oxide support material selected from the group consisting of silica, alumina, or a combination of silica and alumina, said support material containing not greater than about 5 millimoles of hydroxyl groups per gram of support material and a particle size not greater than about 10 microns and a surface area of from about 50 to about 800 m.sup.2 /g in an inert organic liquid medium; (B) mixing said slurry with (2) an alkoxide and stirring the resultant mixture at a temperature of from about -20.degree. C. to about 120.degree. C. for a time sufficient to saturate the surface of the support material; (C) mixing the product form (B) with (3) a titanium compound or a combination of a titanium compound and (4) a vanadium compound and stirring the resultant mixture at a temperature of from about -20.degree. C.
    Type: Grant
    Filed: November 10, 1994
    Date of Patent: January 30, 1996
    Assignee: The Dow Chemical Company
    Inventors: Lee Spencer, Brian W. S. Kolthammer, Miriam P. Ripplinger, Jeffrey J. Wooster, Pak-Wing S. Chum, Jacquelyn A. deGroot
  • Patent number: 5420090
    Abstract: A transition metal containing catalyst useful for the polymerization of .alpha.-olefins is prepared by (A) forming in an inert atmosphere which excludes oxygen and moisture a slurry of (1) a porous inorganic oxide support material selected from the group consisting of silica, alumina, or a combination of silica and alumina, said support material containing not greater than about 5 millimoles of hydroxyl groups per gram of support material and a particle size not greater than about 10 microns and a surface area of from about 50 to about 800 m.sup.2 /g in an inert organic liquid medium; (B) mixing said slurry with (2) an alkoxide and stirring the resultant mixture at a temperature of from about -20.degree. C. to about 120.degree. C. for a time sufficient to saturate the surface of the support material: (C) mixing the product form (B) with (3) a titanium compound or a combination of a titanium compound and (4) a vanadium compound and stirring the resultant mixture at a temperature of from about -20.degree. C.
    Type: Grant
    Filed: February 24, 1993
    Date of Patent: May 30, 1995
    Assignee: The Dow Chemical Company
    Inventors: Lee Spencer, Brian W. S. Kolthammer
  • Patent number: 5231151
    Abstract: A transition metal containing catalyst useful for the polymerization of .alpha.-olefins is prepared by (A) forming in an inert atmosphere which excludes oxygen and moisture a slurry of (1) a porous inorganic oxide support material selected from the group consisting of silica, alumina, or a combination of silica and alumina, said support material containing not greater than about 5 millimoles of hydroxyl groups per gram of support material and a particle size not greater than about 10 microns and a surface area of from about 50 to about 800 m.sup.2 /g in an inert organic liquid medium; (B) mixing said slurry with (2) an alkoxide and stirring the resultant mixture at a temperature of from about -20.degree. C. to about 120.degree. C. for a time sufficient to saturate the surface of the support material; (C) mixing the product form (B) with (3) a titanium compound or a combination of a titanium compound and (4) a vanadium compound and stirring the resultant mixture at a temperature of from about -20.degree. C.
    Type: Grant
    Filed: March 20, 1992
    Date of Patent: July 27, 1993
    Assignee: The Dow Chemical Company
    Inventors: Lee Spencer, Brian W. S. Kolthammer, Miriam P. Ripplinger, Jeffrey J. Wooster, Pak-Wing S. Chum, Jacquelyn A. deGroot