Patents by Inventor Sudarsanan Varaprath

Sudarsanan Varaprath 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).

  • Amorphous silicon hermetic coatings for optical wave guides
    Patent number: 5246734
    Abstract: This invention relates to a method of forming amorphous silicon hermetic coatings on light conducting devices, including optical fibers, wave guides, light pipes, or cables. By the present invention, a halosilane, halodisilane or mixture of halosilanes is thermally decomposed in the vapor phase in the presence of a light conducting device to produce an amorphous silicon hermetic coating on the light conducting device.
    Type: Grant
    Filed: April 2, 1990
    Date of Patent: September 21, 1993
    Assignee: Dow Corning Corporation
    Inventors: Sudarsanan Varaprath, Forrest O. Stark, Keith W. Michael
  • Process for synthesis of acylamino organosilicon compounds
    Patent number: 4933413
    Abstract: Organosilicon compounds containing at least one acylamino-substituted hydrocarbon radical are prepared by reacting an organohydroxysilicon compound containing at least one silicon-bonded hydroxy radical with a base to yield a silanolate. The silanolate is reacted with a cyclic aminosilane compound to form a siloxyalkylamide that is then reacted with an acyl chloride to give the desired product. All reactions can be carried out in a single reaction vessel using a nonaqueous solvent.
    Type: Grant
    Filed: April 10, 1989
    Date of Patent: June 12, 1990
    Assignee: Dow Corning Corporation
    Inventor: Sudarsanan Varaprath
  • Process for the synthesis of acylamino organosilicon compounds
    Patent number: 4861906
    Abstract: Organosilicon compounds containing at least one acylamino-substituted hydrocarbon radical are prepared by reacting an organosilicon compound containing at least one amino-substituted hydrocarbon radical with an acyl halide in a nonaqueous solvent and in the presence of a metal alkoxide in a nonaqueous cosolvent.
    Type: Grant
    Filed: April 10, 1989
    Date of Patent: August 29, 1989
    Assignee: Dow Corning Corporation
    Inventors: Sudarsanan Varaprath, Padmakumari J. Varaprath
  • Silicon-containing coatings and a method for their preparation
    Patent number: 4696834
    Abstract: The invention relates to the formation of silicon-containing coatings from the vapor phase thermal decomposition of halosilanes, polyhalodisilanes, polyhalosilanes or mixtures thereof in the presence of a metal catalyst. The instant invention also relates to the formation of silicon- and carbon-containing coatings and silicon- and titanium-containing coatings from the vapor phase thermal decomposition of alkyl halides and titanium halides, respectively, in the presence of a halosilane, polyhalosilane or halodisilane, and a metal catalyst.
    Type: Grant
    Filed: February 28, 1986
    Date of Patent: September 29, 1987
    Assignee: Dow Corning Corporation
    Inventor: Sudarsanan Varaprath
  • Synthesis of isocoumarins via thallation-olefination of arenes
    Patent number: 4650881
    Abstract: Arenes, such as benzoic acid and substituted benzoic acids, are readily thallated by thallium(III) compounds such as the trifluoroacetate and subsequently reacted with palladium chloride and simple olefins, dienes, allylic halides, vinyl halides, vinyl esters, or unsaturated cyclopropanes or unsaturated cyclobutanes to give isocoumarins.
    Type: Grant
    Filed: April 1, 1985
    Date of Patent: March 17, 1987
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: Richard C. Larock, Sudarsanan Varaprath
  • Organopalladium additions to alkenyl- and methylenecyclopropanes and alkenyl- and methylenecyclobutanes
    Patent number: 4632996
    Abstract: (Pi-allyl)palladium compounds are prepared by organopalladium addition to alkenyl- or methylenecyclopropanes or alkenyl- or methylenecyclobutanes. The reaction is conducted in the presence of a palladium salt and involves a novel ring-opening process and a subsequent rearrangement to provide a regioselective route to (pi-allyl)palladium compounds.
    Type: Grant
    Filed: August 5, 1985
    Date of Patent: December 30, 1986
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: Richard C. Larock, Sudarsanan Varaprath