Patents by Inventor Thoi H. Ho

Thoi H. Ho 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: 6384139
    Abstract: At least partially vulcanized elastomers are described, these elastomers obtained by at least partially crosslinking (1) an elastomeric polymer containing reactive substituents with (2) a crosslinking agent (a) containing two or more reactive substituents differing from those contained in the elastomeric polymer, and (b) having a number average molecular weight less than about 2000, each of the reactive substituents selected (i) such that those of the elastomer will react with those of the crosslinking agent to at least partially crosslink the elastomer, and (ii) from the group consisting of carboxylic acid, carboxylic anhydride, carboxylic acid salt, carbonyl halide, hydroxy, epoxy, and isocyanate.
    Type: Grant
    Filed: January 12, 1999
    Date of Patent: May 7, 2002
    Assignee: The Dow Chemical Company
    Inventors: Thoi H. Ho, Morgan M. Hughes, Robert T. Johnston, Jimmy D. Allen
  • Publication number: 20020049269
    Abstract: The present invention relates to a method of making improved polyolefinic elastic articles from cured, irradiated or crosslinked amorphous ethylene interpolymers. In particular, the invention relates to a method of making a shaped article (e.g. film or fiber) characterized by improved elevated temperature elasticity as well as washability and dryability. The inventive elastic article comprises a substantially cured, irradiated, or crosslinked (or curable, irradiated or crosslinkable) homogeneously branched ethylene interpolymer characterized as having a density less than 0.90 g/cm3 and containing at least one nitrogen-containing stabilizer. The improved elastic article of the present invention is particularly suitable for use in applications where good elasticity must be maintained at elevated temperatures and after laundering such as, for example, elastic waist bands of undergarments and other clothing.
    Type: Application
    Filed: May 27, 1999
    Publication date: April 25, 2002
    Inventors: THOI H. HO, EDWARD N. KNICKERBOCKER, REXFORD A. MAUGANS
  • Patent number: 6376623
    Abstract: The present invention includes a process of preparing a coupled polymer comprising heating an admixture containing (1) at least one elastomer comprising ethylene and at least one comonomer which is selected from alpha olefins having at least 3 carbon atoms, dienes and combinations thereof and (2) a coupling amount at least one poly(sulfonyl azide) to at least the decomposition temperature of the poly(sulfonyl azide) for a period sufficient for decomposition of at least about 80 weight percent of the poly(sulfonyl azide) and sufficient to result in a coupled polymer having a gel content of less than about 2 weight percent.
    Type: Grant
    Filed: August 5, 1998
    Date of Patent: April 23, 2002
    Assignee: The Dow Chemical Company
    Inventors: Wendy D. Hoenig, Che-I Kao, Teresa Karjala, Clark H. Cummins, Michael J. Mullins, Thoi H. Ho, H. Craig Silvis
  • Patent number: 6359073
    Abstract: The invention includes a process of reacting a poly(sulfonyl azide) with a polymer comprising steps (a) forming a first admixture of a first amount of a first polymer or in a liquid which does not require removal from the polymer and a poly(sulfonyl azide); (b) then forming a second admixture of the first admixture with a second amount of at least one second polymer; and (c) heating the second admixture at lest to the decomposition temperature of the coupling agent for a time sufficient to result in coupling of polymer chains. The invention further includes all compositions obtainable by processes of the invention as well as blends of those compositions with one or more polymers of compositions different from the first or second polymer or the product of a process of the invention.
    Type: Grant
    Filed: October 23, 2000
    Date of Patent: March 19, 2002
    Assignee: The Dow Chemical Company
    Inventors: David A. Babb, Che-I Kao, Wendy D. Hoenig, Michael E. Rowland, Clark H. Cummins, H. Craig Silvis, Michael J. Mullins, Thoi H. Ho
  • Patent number: 6325956
    Abstract: The invention includes a process comprising (a) forming a polymeric admixture including at least one polyolefin which has been prepared using a single site catalyst and at least a crosslinking amount of at least one poly(sulfonyl azide) crosslinking agent; (b) shaping the resulting admixture; and (c) heating the resulting shaped admixture to a temperature at least the decomposition temperature of the crosslinking agent. The steps take place in any sequence and optionally include substeps. The single site catalyst is preferably a constrained geometry or metallocene catalyst, but optionally another transition metal catalyst which is not a traditional Ziegler Natta Ti/MgCl2 catalyst such as a vanadium catalyst. The invention further includes all compositions obtainable by the process of the invention as well as all articles formed from these compositions.
    Type: Grant
    Filed: August 26, 1998
    Date of Patent: December 4, 2001
    Assignee: The Dow Chemical Company
    Inventors: Bharat I. Chaudhary, Thoi H. Ho, Seema V. Karande, Che-I. Kao, Robert H. Terbrueggen, David A. Babb, Clark H. Cummins, Michael J. Mullins, H. Craig Silvis
  • Patent number: 6323285
    Abstract: The subject invention pertains to heteromorphic polymer compositions characterized as comprising: (a) a homogeneous linear or substantially linear ethylene/&agr;-olefin interpolymer backbone; and (b) a branch appending from the backbone, which branch comprises an ethylene homopolymer or ethylene/&agr;-olefin interpolymer having a density which is at least 0.004 g/cm3 greater than that of the backbone. At least one of the backbone polymer or the branch polymer may be optionally functionalized to promote adhesion to polar surfaces. The heteromorphic polymer compositions of the invention exhibit enhanced upper service temperature. Also disclosed is a process for preparing the heteromorphic polymer compositions of the invention.
    Type: Grant
    Filed: January 9, 1998
    Date of Patent: November 27, 2001
    Assignee: The Dow Chemical Company
    Inventors: Robert T. Johnston, Evelyn J. Morrison, Debra J. Mangold, Thoi H. Ho
  • Patent number: 6284842
    Abstract: The invention includes a process of preparing a coupled polymer blend comprising heating an admixture containing (1) a polymer blend containing: (A) from 1 to 99 weight percent of one ore more &agr;-olefin/hindered vinyl monomer substantially random interpolymers, each having been made from monomer components comprising: (1) from 0.5 to 65 mole percent of either (a) at least one vinyl aromatic monomer, or (b) at least one hindered aliphatic vinyl monomer, or (c) a combination of at least one vinyl aromatic monomer and at least one hindered aliphatic vinyl monomer; and (2) from 35 to 99.
    Type: Grant
    Filed: August 26, 1998
    Date of Patent: September 4, 2001
    Assignee: The Dow Chemical company
    Inventors: Thoi H. Ho, Robert H. Terbrueggen, H. Craig Silvis, Clark H. Cummins, Michael J. Mullins
  • Patent number: 6277916
    Abstract: This invention includes a process for forming a thermoplastic vulcanizate comprising: (a) admixing a C—H insertion curing agent with at least one elastomeric phase polymer to form a first admixture; (b) admixing at least one non-elastomeric polyolefin with the first admixture to form a second admixture; and (c) heating the second admixture to a temperature at least the decomposition temperature of the curing agent to crosslink the elastomeric phase while mixing the admixture to an extent sufficient to result in the formation of a thermoplastic material, hereinafter referred to as a thermoplastic vulcanizate, and optionally including an additional step (d) of shaping the resulting thermoplastic vulcanizate, especially by heating and foaming or molding the TPV.
    Type: Grant
    Filed: February 25, 1999
    Date of Patent: August 21, 2001
    Assignee: The Dow Chemical Company
    Inventors: Robert H. Terbrueggen, Ray E. Drumright, Thoi H. Ho
  • Publication number: 20010002075
    Abstract: The invention includes a process comprising (a) forming a polymeric admixture including at least one polyolefin which has been prepared using a single site catalyst and at least a crosslinking amount of at least one poly(sulfonyl azide) crosslinking agent; (b) shaping the resulting admixture; and (c) heating the resulting shaped admixture to a temperature at least the decomposition temperature of the crosslinking agent. The steps take place in any sequence and optionally include substeps. The single site catalyst is preferably a constrained geometry or metallocene catalyst, but optionally another transition metal catalyst which is not a traditional Ziegler Natta Ti/MgCl2 catalyst such as a vanadium catalyst.
    Type: Application
    Filed: August 26, 1998
    Publication date: May 31, 2001
    Inventors: BHARAT CHAUDHARY, THOI H. HO, SEEMA KARANDE, CHE-I KAO, ROBERT H. TERBRUEGGEN, DAVID A. BABB, CLARK H. CUMMINS, MICHAEL J. MULLINS, H. CRAIG SILVIS
  • Patent number: 6211302
    Abstract: The invention includes a process of preparing a coupled polymer comprising heating an admixture containing (1) at least one interpolymer of an alpha olefin and vinyl aromatic monomer and (2) a coupling amount of at least one poly(sulfonyl azide) to at least the decomposition temperature of the poly(sulfonyl azide) for a period sufficient for decomposition of at least about 80 weight percent of the poly(sulfonyl azide) and sufficient to result in a coupled polymer. The polymer preferably. comprises ethylene, and a vinyl aromatic monomer, preferably styrene. The amount of poly(sulfonyl azide) is preferably from about 0.01 to about 1 weight percent of the interpolymer and the reaction preferably takes place at a temperature greater than about 150° C., more preferably 185° C. The process optionally and in one preferred embodiment additionally comprises steps (b) fabricating an article from the coupled polymer and (c) crosslinking the fabricated coupled polymer.
    Type: Grant
    Filed: August 5, 1998
    Date of Patent: April 3, 2001
    Assignee: The Dow Chemical Company
    Inventors: Thoi H. Ho, Ray E. Drumright, Robert H. Terbrueggen, Clark H. Cummins, Michael J. Mullins, H. Craig Silvis
  • Patent number: 6184290
    Abstract: The present invention is at least a two-component thermoplastic elastomeric composition comprising at least one block copolymer wherein the composition has essentially the same comparative elasticity, high temperature serviceability and hardness as the unmodified, undiluted (neat) block copolymer portion of the composition. The composition also shows enhanced thermal stability and processibility and is well suited for fabricating elastic moldings, films and fibers as well as for formulating with asphalts, adhesives and sealants. The novel thermoplastic elastomeric composition comprises (a) from about 50 to about 99 percent by weight of at least one block copolymer and (b) about 1 to about 50 percent by weight of at least one ethylene interpolymer having a density from about 0.855 g/cc to about 0.905 g/cc, wherein the ethylene interpolymer in the amount employed is a substantially inert extender of the block copolymer and the composition is further characterized as having: i.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: February 6, 2001
    Assignee: The Dow Chemical Company
    Inventors: Wasif K. Ahmed, Antonio Batistini, Stephen R. Betso, Martin J. Guest, Thoi H. Ho, George W. Knight, Deepak R. Parikh, Rajen M. Patel
  • Patent number: 6184291
    Abstract: The present invention is at least a two-component thermoplastic elastomeric composition comprising at least one block copolymer wherein the composition has essentially the same comparative elasticity, high temperature serviceability and hardness as the unmodified, undiluted (neat) block copolymer portion of the composition. The composition also shows enhanced thermal stability and processibility and is well suited for fabricating elastic moldings, films and fibers as well as for formulating with asphalts, adhesives and sealants. The novel thermoplastic elastomeric composition comprises (a) from about 50 to about 99 percent by weight of at least one block copolymer and (b) about 1 to about 50 percent by weight of at least one ethylene interpolymer having a density from about 0.855 g/cc to about 0.905 g/cc, wherein the ethylene interpolymer in the amount employed is a substantially inert extender of the block copolymer and the composition is further characterized as having: i.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: February 6, 2001
    Assignee: The Dow Chemical Company
    Inventors: Wasif K. Ahmed, Antonio Batistini, Stephen R. Betso, Martin J. Guest, Thoi H. Ho, George W. Knight, Deepak R. Parikh, Rajen M. Patel
  • Patent number: 6143829
    Abstract: The invention includes a process of reacting a poly(sulfonyl azide) with a polymer comprising steps (a) forming a first admixture, hereinafter referred to as a concentrate, of a first amount of a first polymer or in a liquid which does not require removal from the polymer, hereinafter diluent, and a poly(sulfonyl azide); (b) then forming a second admixture of the first admixture with a second amount of at least one second polymer, hereinafter second polymer composition; and (c) heating the second admixture at least to the decomposition temperature of the coupling agent for a time sufficient to result in coupling of polymer chains. The diluent is preferably a non-volatile, non-polar compound such as mineral oil in which the poly(sulfonyl azide) is sufficiently miscible to disperse the poly(sulfonyl azide) in the second polymer.
    Type: Grant
    Filed: August 13, 1998
    Date of Patent: November 7, 2000
    Assignee: The Dow Chemical Company
    Inventors: David A. Babb, Wendy D. Hoenig, Che-I Kao, Michael E. Rowland, Clark H. Cummins, Michael J. Mullins, H. Craig Silvis, Thoi H. Ho
  • Patent number: 5990244
    Abstract: A polymer blend comprising:a) a syndiotactic monovinylidene aromatic polymer,b) a polyamide,c) a compatibilizing polymer for a) and b),d) a rubbery polyolefin impact modifier, optionally extended with an oil,e) a domain forming rubbery polymer,f) a polar group functionalized rubbery polyolefin, andg) optionally, a compatibilizing polymer for a) and d).
    Type: Grant
    Filed: September 1, 1998
    Date of Patent: November 23, 1999
    Assignee: The Dow Chemical Company
    Inventors: John M. Warakomski, David H. Bank, Thoi H. Ho
  • Patent number: 5977271
    Abstract: The subject invention provides a thermoset elastomer comprising a crosslinked pseudorandom or substantially random interpolymer of: (a) from 15 to 70 weight percent of at least one .alpha.-olefin, (b) from 30 to 70 weight percent of at least one vinylidene aromatic compound, and (c) from 0 to 15 weight percent of at least one diene. The subject invention further provides a thermoplastic vulcanizate comprising the thermoset elastomers of the invention as provided in a thermoplastic polyolefin matrix. The subject invention further provides processes for preparing the inventive thermoset elastomers and thermoplastic vulcanizates, as well as parts fabricated therefrom. The inventive materials have a superior balance of properties, as compared to EPM and EPDM based materials. The subject invention also pertains to foams and methods for their preparation.
    Type: Grant
    Filed: August 27, 1997
    Date of Patent: November 2, 1999
    Assignee: The Dow Chemical Company
    Inventors: Kevin W. McKay, Francis J. Timmers, Edwin R. Feig, Thoi H. Ho, Seema V. Karande
  • Patent number: 5869591
    Abstract: The subject invention provides a thermoset elastomer comprising a crosslinked pseudorandom or substantially random interpolymer of: (a) from 15 to 70 weight percent of monomer units derived from at least one a-olefin, (b) from 30 to 70 weight percent of monomer units derived from at least one vinylidene aromatic compound, and (c) from 0 to 15 weight percent of monomer units derived from at least one diene. The subject invention further provides a thermoplastic vulcanizate comprising the thermoset elastomers of the invention as provided in a thermoplastic polyolefin matrix. The subject invention further provides processes for preparing the inventive thermoset elastomers and thermoplastic vulcanizates, as well as parts fabricated therefrom. The inventive materials have a superior balance of properties, as compared to EPM and EPDM based materials. The subject invention also pertains to foams and methods for their preparation.
    Type: Grant
    Filed: August 27, 1997
    Date of Patent: February 9, 1999
    Assignee: The Dow Chemical Company
    Inventors: Kevin W. McKay, Francis J. Timmers, Edwin R. Feig, Thoi H. Ho, Seema V. Karande
  • Patent number: 5321116
    Abstract: A process for preparation of a random copolycarbonate from an ortho-substituted dihydric phenol and a non-ortho-substituted dihydric phenol.
    Type: Grant
    Filed: April 5, 1993
    Date of Patent: June 14, 1994
    Assignee: The Dow Chemical Company
    Inventors: Maurice J. Marks, Thoi H. Ho
  • Patent number: 5276078
    Abstract: Improved thermoplastic resinous blends are disclosed comprising a carbonate polymer; an organophosphorus compound; a fluorinated polymer; and a halogenated diphenol oligocarbonate.
    Type: Grant
    Filed: January 13, 1992
    Date of Patent: January 4, 1994
    Assignee: The Dow Chemical Company
    Inventors: Samuel A. Ogoe, Thoi H. Ho, Robert W. Ranger
  • Patent number: 5212282
    Abstract: A process for preparation of a random copolycarbonate from an ortho-substituted dihydric phenol and a non-ortho-substituted dihydric phenol.
    Type: Grant
    Filed: July 15, 1991
    Date of Patent: May 18, 1993
    Assignee: The Dow Chemical Company
    Inventors: Maurice J. Marks, Thoi H. Ho
  • Patent number: 5109044
    Abstract: Ignition resistant halo aromatic containing polymer compositions are disclosed which are mixtures of a blend of styrene-butadiene-acrylonitrile copolymers and carbonate polymers, 0.001 to 20% by weight of a high elastic memory polytetrafluoroethylene having a heat shrinkage equal to or greater than 15%, and 0.1 to 30% by weight of a halogenated aryl phosphate having at least one bromoaryl group.
    Type: Grant
    Filed: October 24, 1989
    Date of Patent: April 28, 1992
    Assignee: The Dow Chemical Company
    Inventors: Thoi H. Ho, Samuel A. Ogoe, Todd R. Mayer