Patents by Inventor Christopher P. Christenson

Christopher P. Christenson 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: 5721198
    Abstract: Elastic solids having reversible stress-induced fluidity are prepared, e.g., by combining liquid formulations with a crystalline mixed metal hydroxide conforming substantially to the formulaLi.sub.m D.sub.d T(OH).sub.(m+2d+3+n.multidot.a) (A.sup.n).sub.a .multidot.xH.sub.2 Owhere m is amount of Li, d is amount of divalent metal D, T is a trivalent metal, A represents at least one anion or negative-valence radical of valence n and a is the amount of A, and xH.sub.2 O represents excess waters of hydration, if any. These make useful coatings.The instantly reversible fluidization of these unique elastic solids may be expressed as:.sigma.=k.sub..alpha. .epsilon. when .epsilon.<F, for the solid phase; and.sigma.=f(d.epsilon.'/dt) when .epsilon.'>F, (this equation represents a generalized form for the usual theological equations); for a cycle of .epsilon., -xF <.epsilon.<xF, and when .epsilon.' equals 0 the liquid phase changes back to the solid phase, andwhere the symbol .sigma. represents stress; k.
    Type: Grant
    Filed: August 18, 1995
    Date of Patent: February 24, 1998
    Assignee: The Dow Chemical Company
    Inventors: John L. Burba, III, Christopher P. Christenson
  • Patent number: 5443761
    Abstract: Elastic solids having reversible stress-induced fluidity are prepared, e.g., by combining liquid formulations with a crystalline mixed metal hydroxide conforming substantially to the formulaLi.sub.m D.sub.d T(OH).sub.(m+2d+3+n.a) (A.sup.n).sub.a.xH.sub.2 Owhere m is amount of Li, d is amount of divalent metal D, T is a trivalent metal, A represents at least one anion or negative-valence radical of valence n and a is the amount of A, and xH.sub.2 O represents excess waters of hydration, if any. These make useful coatings.The instantly reversible fluidization of these unique elastic solids may be expressed as:.tau.=ka.epsilon.,When .epsilon.<F, for the solid phase; and.epsilon.=f(d.epsilon.'/dt)when .epsilon.'<F, (this equation represents a generalized form for the usual rheological equations); for a cycle of .epsilon., -xF<.epsilon.<xF, and when .epsilon.' equals 0 the liquid phase changes back to the solid phase, andwhere the symbol .sigma. represents stress; k.sub.
    Type: Grant
    Filed: October 11, 1991
    Date of Patent: August 22, 1995
    Assignee: The Dow Chemical Company
    Inventors: John L. Burba, III, Christopher P. Christenson
  • Patent number: 5418271
    Abstract: Coating formulations which behave as elastic solids having reversible stress-induced fluidity are prepared by creating a fluid having distributed therein effective amounts of ionic charge sites and countercharge sites. For instance, elastic solids having reversible stress-induced fluidity are prepared by combining liquid formulations with a dispersion of a small, but effective, amount of at least one crystalline mixed metal hydroxide conforming substantially to the formulaLi.sub.m D.sub.d T(OH).sub.(m+2d+3+n.multidot.a) (A.sup.n).sub.a .multidot.xH.sub.2 Owhere m is zero to one, D is a divalent metal, d is from zero to 4, T is a trivalent metal, A represents at least one anion or negative-valence radical of valence n and a is the amount of A, where n is 1 or more, (m+2d+3+n.multidot.a) is equal to or greater than 3, (m+d) is greater than zero, and xH.sub.2 O represents excess waters of hydration, if any.
    Type: Grant
    Filed: October 11, 1991
    Date of Patent: May 23, 1995
    Assignee: The Dow Chemical Company
    Inventors: John L. Burba, III, Peter A. Doty, Christopher P. Christenson, Susan K. Falcone, Andrea H. Hazlitt, Thomas M. Knobel, Wilfred C. Meyer, Arthur E. Read, Jr., Edgar F. Hoy, Avis L. McCrary, Ha Q. Pham, Stanley F. Simpson, Steve A. Sims, Betty J. Smith
  • Patent number: 4905504
    Abstract: A foam pulse rheometer measures the total integrated stress response of a foaming polymer to a short duration strain pulse applied to the polymer, from which can be calculated the equilibrium modulus and the zero shear viscosity of the foaming polymer during the foaming reaction. A shear plate mounted to a load cell above a jacket extends downwardly into a foaming polymer within the jacket. Under the application of a vertical square wave strain pulse to the jacket, the load cell senses the shear force exerted upon the shear plate by the foaming polymer. Simultaneously, a video camera and recorder monitors the surface area of the plate acted upon by the jacket. For each pulse, simultaneously occurring discrete sensed force values and discrete monitored surface area values can be used to compute the total integrated stress response, from which can be calculated the equilibrium modulus and the zero shear viscosity.
    Type: Grant
    Filed: March 15, 1989
    Date of Patent: March 6, 1990
    Assignee: The Dow Chemical Company
    Inventors: Craig J. Carriere, David H. Bank, Christopher P. Christenson
  • Patent number: 4843138
    Abstract: Improved low temperature properties of polyureaurethane are obtained, such as low glass transition temperatures and reduced bending moduli at -400.degree. C., by the use of relatively high moleuclar weight polyether polyol intermediates. The polyureaurethane is made by reacting the polyether polyol intermediate with a diisocyanate and subsequent cure with a metal halide salt complex of methylenedianiline.
    Type: Grant
    Filed: February 8, 1988
    Date of Patent: June 27, 1989
    Assignees: The Firestone Tire & Rubber Company, The Dows Chemical Company
    Inventors: Joseph H. Tazewell, Christopher P. Christenson, Robert B. Turner, Manuel Gonzales, Jr.
  • Patent number: 4382997
    Abstract: A method for preparing spinel (MgAl.sub.2 O.sub.4) surfaces on alumina or alumino silicate articles or shapes by exposure of the article or shape to molten or vaporous magnesium or magnesium alloy for from two to ten hours under nonpyrophoric conditions.
    Type: Grant
    Filed: September 4, 1980
    Date of Patent: May 10, 1983
    Assignee: The Dow Chemical Company
    Inventors: Walter W. Henslee, Stanley J. Morrow, John S. Lindsey, Christopher P. Christenson, Hans H. Schwantje
  • Patent number: 4380616
    Abstract: Olefins are polymerized in the presence of chromium-containing catalysts which have been improved by depositing the chromium onto the inorganic oxide support in the vapor phase rather than as an inorganic or organic compound. The resulting polymers exhibit a higher molecular weight as compared to those polymers prepared in the presence of such chromium-containing catalysts prepared in the conventional manner.
    Type: Grant
    Filed: May 14, 1981
    Date of Patent: April 19, 1983
    Assignee: The Dow Chemical Company
    Inventors: Fred L. Vance, Jr., Rafael E. Guerra, Christopher P. Christenson
  • Patent number: 4362654
    Abstract: Inorganic oxide supported chromium-containing catalysts are improved by depositing the chromium onto the inorganic oxide support in the vapor phase rather than as an inorganic or organic compound. Polymers resulting from polymerizing one or more .alpha.-olefins in the presence of such catalysts exhibit a higher molecular weight as compared to those polymers prepared in the presence of such chromium-containing catalysts prepared in the conventional manner.
    Type: Grant
    Filed: May 14, 1981
    Date of Patent: December 7, 1982
    Assignee: The Dow Chemical Company
    Inventors: Fred L. Vance, Jr., Rafael E. Guerra, Christopher P. Christenson
  • Patent number: 4249939
    Abstract: Copper is removed from spent solutions of complexing agents containing cuprous aluminum tetrahalide, such as CuAlCl.sub.4.toluene by (1) contacting said solutions with water so as to form a precipitate of cuprous halide, an aqueous phase and an organic phase; (2) oxidizing the cuprous halide to cupric halide thereby rendering it water soluble; (3) separating the organic phase and aqueous phase, (4) contacting the aqueous phase with an environmentally suitable metal higher than copper from the electromotive series, such as aluminum, thereby precipitating copper metal and (5) separating the precipitated copper metal from the aqueous salt-containing mixture.Alternatively, the spent complex solutions can be contacted with 1 molar to 6 molar aqueous solution of a non-oxidizing acid such as HCl thereby eliminating the necessity of the oxidizing step (2) since the cuprous halide is soluble in the acidified aqueous phase.
    Type: Grant
    Filed: January 3, 1980
    Date of Patent: February 10, 1981
    Assignee: The Dow Chemical Company
    Inventors: Christopher P. Christenson, Gary M. McNamee, Ralph H. Delaune
  • Patent number: 4100183
    Abstract: Cuprous aluminum tetrahalide complexing agents are prepared from cuprous halide such as cuprous chloride contaminated with cupric halide by a method which reduces the cupric ion to the cuprous ion by treating the contaminated cuprous halide with an organo metal compound, such as metal alkyls, metal alkyl halide or metal alkoxides such as diethyl aluminum chloride prior to preparation of the complexing agent by reacting the cuprous halide with an aluminum trihalide such as aluminum trichloride. The pretreatment to remove the cupric ions reduces the amount of aromatic tars formed in processes employing the complexing agents.
    Type: Grant
    Filed: May 2, 1977
    Date of Patent: July 11, 1978
    Assignee: The Dow Chemical Company
    Inventors: Christopher P. Christenson, John W. Faller, Gary M. McNamee
  • Patent number: 4099984
    Abstract: Heat exchangers which become fouled during cooling of CuAlCl.sub.4 .multidot.solvent (such as toluene) solutions employed in extracting carbon monoxide from acetylene is cleaned by circulating through the fouled exchanger a solvent solution of CuAlCl.sub.4 .multidot.solvent containing aluminum trichloride.
    Type: Grant
    Filed: May 3, 1977
    Date of Patent: July 11, 1978
    Assignee: The Dow Chemical Company
    Inventors: Christopher P. Christenson, Gary M. McNamee