Patents by Inventor Sundar Kilnagar Venkataraman
Sundar Kilnagar Venkataraman 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).
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Patent number: 7652211Abstract: The present invention relates to jacketed cable especially useful for plenum enclosures of buildings, the jacket of the cable comprising perfluoropolymer, such as tetrafluoroethylene/hexafluoropropylene copolymer, and inorganic char-forming agent, and preferably an additional ingredient, hydrocarbon polymer, the cable passing the NFPA-255 burn test.Type: GrantFiled: January 19, 2005Date of Patent: January 26, 2010Assignee: E. I. du Pont de Nemours and CompanyInventors: Yevgeniy I. Globus, Mark A. Jozokos, John L. Netta, George Martin Pruce, Sundar Kilnagar Venkataraman
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Patent number: 7638709Abstract: FEP compositions are provided that provide foam insulation in coaxial cable that surpasses the return loss obtained when PFA is used to make the foamed insulation, one composition comprising a blend of tetrafluoroethylene/hexafluoropropylene copolymers, one of said copolymers exhibiting a strip force of at least about 3 lbf (13.3 N) and another of said copolymers exhibiting a strip force no greater than about 2.5 lbf (11.1 N), said blend exhibiting a strip force of at least about 3 lbf (13.3 N), each said strip force being the force necessary to break adhesion between conductor and said one of said copolymers, said another of said copolymers, and said blend, respectively, and another composition comprising tetrafluoroethylene/hexafluoropropylene copolymer having an MFR of no greater than about 16 g/10 min and containing —CF3 end groups and an effective amount of wire affinity end groups to exhibit a strip force of at least about 3 lbf (13.Type: GrantFiled: May 8, 2008Date of Patent: December 29, 2009Assignee: E. I. du Pont de Nemours and CompanyInventors: Robert D. Kenny, John L. Netta, Sundar Kilnagar Venkataraman, Robert Thomas Young
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Patent number: 7592406Abstract: The combination of a hinge and an insulated wire is provided, wherein the hinge is capable of closing and opening to an angle of at least 90°, the insulated wire being secured by the hinge so as to fold when said hinge is closed and to unfold when said hinge is opened, the insulation on the wire comprising fluoropolymer, such as tetrafluoroethylene/-hexafluoropropylene copolymer or tetrafluoroethylene/perfluoro(methyl vinyl ether)/perfluoro(propyl vinyl ether) copolymer, each polymer having a melting point of 260 to 290° C. and MIT Flex Life of at least about 15,000 cycles, the hinge being useful in such electronic devices as a laptop computer or a clamshell cell phone, attaching the keyboard and screen portion to one another, the insulation being capable of repeated opening and closing of the hinge without cracking of the insulation.Type: GrantFiled: October 9, 2007Date of Patent: September 22, 2009Assignee: E.I. du Pont de Nemours and CompanyInventors: Robert D. Kenny, Philip S. Smith, Patricia A. Tooley, Sundar Kilnagar Venkataraman
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Patent number: 7579418Abstract: The present invention relates to the process of extruding melt drawing fluoropolymer onto conductor to form insulated conductor at a line speed of at least 533 m/min and having no more than 10 sparks and no more than 2 lumps/13.7 km of insulated conductor under conditions that comprise an adequate process window to allow for these results to be obtained at different conditions within the process window. The invention identifies the critical parameters for achieving this process window, namely melt flow rate of the fluoropolymer, preferably being 30±3 g/10 min, and the melt temperature of the extruding/melt-drawing step, preferably being 393° C.±6° C.Type: GrantFiled: April 27, 2004Date of Patent: August 25, 2009Assignee: E. I. du Pont de Nemours and CompanyInventors: Patrick Anthony DeFeo, Glenn W. Heffner, Niall D. McKee, Sundar Kilnagar Venkataraman
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Publication number: 20090186956Abstract: The present invention discloses a foamable composition. The foamable composition includes a partially-crystalline melt processible perfluoropolymer and a foam nucleating package. The foamable composition has a uniform foam cell size where the foam cell size of at least 90% of the foamed cells is 50 micrometers or less. The foam nucleating package ranges from 0.1 to 10 wt % of the combined weight of the perfluoropolymer and the foam nucleating package.Type: ApplicationFiled: March 24, 2009Publication date: July 23, 2009Applicant: E.I. DU PONT DE NEMOURS AND COMPANYInventors: Sundar Kilnagar Venkataraman, Robert Thomas Young
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Patent number: 7473848Abstract: Communication cable is provided comprising a twisted pair of polymer insulated conductors, the twisting to form the twisted pair forcing the surface of polymer insulation of each polymer-insulated conductor of said polymer-insulated conductors into contact with one another, the polymer insulation of each polymer-insulated conductor including (i) a foamed portion being crushable by the forcing together of the contacting surfaces of the polymer insulation of each of the polymer-insulated conductors and (ii) a crush-resistant portion extending radially within said insulation into the foamed portion and being present where the surface of the polymer-insulated conductors are into said contact with one another, thereby protecting the foamed portion from crushing by the forcing together of the contacting surfaces.Type: GrantFiled: April 10, 2008Date of Patent: January 6, 2009Assignee: E.I. duPont de Nemours and CompanyInventors: Robert D. Kenny, John L. Netta, Gary Thuot, Sundar Kilnagar Venkataraman, Robert Thomas Young
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Patent number: 7459498Abstract: The present invention relates to plenum cables jacketed with a composition comprising perfluoropolymer, inorganic char-forming agent, and hydrocarbon polymer, which passes the NFPA-255 burn test.Type: GrantFiled: January 19, 2005Date of Patent: December 2, 2008Assignees: E. I. du Pont de Nemours and Company, Alpha Gary CorporationInventors: Yevgeniy I. Globus, Mark A. Jozokos, John L. Netta, George Martin Pruce, Sundar Kilnagar Venkataraman
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Publication number: 20080283271Abstract: FEP compositions are provided that provide foam insulation in coaxial cable that surpasses the return loss obtained when PFA is used to make the foamed insulation, one composition comprising a blend of tetrafluoroethylene/hexafluoropropylene copolymers, one of said copolymers exhibiting a strip force of at least about 3 lbf (13.3 N) and another of said copolymers exhibiting a strip force no greater than about 2.5 lbf (11.1 N), said blend exhibiting a strip force of at least about 3 lbf (13.3 N), each said strip force being the force necessary to break adhesion between conductor and said one of said copolymers, said another of said copolymers, and said blend, respectively, and another composition comprising tetrafluoroethylene/hexafluoropropylene copolymer having an MFR of no greater than about 16 g/10 min and containing —CF3 end groups and an effective amount of wire affinity end groups to exhibit a strip force of at least about 3 lbf (13.Type: ApplicationFiled: May 8, 2008Publication date: November 20, 2008Applicant: E. I. DU PONT DE NEMOURS AND COMPANYInventors: Robert D. Kenny, John L. Netta, Sundar Kilnagar Venkataraman, Robert Thomas Young
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Publication number: 20080161435Abstract: A process for making an extruded foamable composition is disclosed where the foamable composition includes a partially-crystalline melt processable perfluoropolymer and a foam nucleating package. The process makes a foamed product having uniform foam cell size at high speeds without loss of product quality.Type: ApplicationFiled: December 19, 2007Publication date: July 3, 2008Applicant: E. I. DU PONT DE NEMOURS AND COMPANYInventors: Sundar Kilnagar Venkataraman, Robert Thomas Young
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Publication number: 20080149899Abstract: The present invention discloses a foamable composition. The foamable composition includes a partially-crystalline melt processible perfluoropolymer and a foam nucleating package. The foamable composition has a uniform foam cell size where the foam cell size of at least 90% of the foamed cells is 50 micrometers or less. The foam nucleating package ranges from 0.1 to 10 wt % of the combined weight of the perfluoropolymer and the foam nucleating package.Type: ApplicationFiled: December 19, 2007Publication date: June 26, 2008Applicant: E. I. DU PONT DE NEMOURS AND COMPANYInventors: Sundar Kilnagar Venkataraman, Robert Thomas Young
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Publication number: 20080153936Abstract: The present invention discloses an article made from a foamable thermoplastic polymer composition. The foamable composition of the article includes a partially-crystalline melt processible perfluoropolymer and a foam nucleating package. The foamable composition of the article has a uniform foam cell size where the foam cell size of at least 90% of the foamed cells is 50 micrometers or less. The foam nucleating package ranges from 0.1 to 10 wt % of the combined weight of the perfluoropolymer and the foam nucleating package.Type: ApplicationFiled: December 19, 2007Publication date: June 26, 2008Applicant: E. I. DU PONT DE NEMOURS AND COMPANYInventors: Sundar Kilnagar Venkataraman, Robert Thomas Young
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Publication number: 20080090065Abstract: The combination of a hinge and an insulated wire is provided, wherein the hinge is capable of closing and opening to an angle of at least 90°, the insulated wire being secured by the hinge so as to fold when said hinge is closed and to unfold when said hinge is opened, the insulation on the wire comprising fluoropolymer, such as tetrafluoroethylene/-hexafluoropropylene copolymer or tetrafluoroethylene/perfluoro(methyl vinyl ether)/perfluoro(propyl vinyl ether) copolymer, each polymer having a melting point of 260 to 290° C. and MIT Flex Life of at least about 15,000 cycles, the hinge being useful in such electronic devices as a laptop computer or a clamshell cell phone, attaching the keyboard and screen portion to one another, the insulation being capable of repeated opening and closing of the hinge without cracking of the insulation.Type: ApplicationFiled: October 9, 2007Publication date: April 17, 2008Inventors: Robert D. Kenny, Philip S. Smith, Patricia A. Tooley, Sundar Kilnagar Venkataraman
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Publication number: 20040232580Abstract: The present invention relates to the process of extruding melt drawing fluoropolymer onto conductor to form insulated conductor at a line speed of at least 533 m/min and having no more than 10 sparks and no more than 2 lumps/13.7 km of insulated conductor under conditions that comprise an adequate process window to allow for these results to be obtained at different conditions within the process window. The invention identifies the critical parameters for achieving this process window, namely melt flow rate of the fluoropolymer, preferably being 30±3 g/10 min, and the melt temperature of the extruding/melt-drawing step, preferably being 393° C.±6° C.Type: ApplicationFiled: April 27, 2004Publication date: November 25, 2004Inventors: Patrick Anthony Defeo, Glenn W. Heffner, Niall D. Mckee, Sundar Kilnagar Venkataraman
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Patent number: 5912278Abstract: Fabricated articles of fluoropolymer are foamed by heating the articles to a deformable state, pressurizing the heated article with supercritical CO.sub.2, depressurizing the pressurized heated article while still in the foamable state, whereby said CO.sub.2 foams said article, and cooling the resultant foamed article.Type: GrantFiled: October 23, 1997Date of Patent: June 15, 1999Assignee: E. I. du Pont de Nemours and CompanyInventor: Sundar Kilnagar Venkataraman
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Patent number: 5885494Abstract: Fluoropolymer is advantageously foamed by first forming a composite structure of a layer of the fluoropolymer to be foamed and a layer of different material such as a different fluoropolymer not to be foamed, followed by heating the composite structure to the foamable state for the layer of fluoropolymer to be foamed, pressurizing the heated composite structure with supercritical carbon dioxide, rapidly depressurizing the heated composite structure, whereby the foamable layer foams and the other layer foams less or not at all, and cooling the foamed composite structure.Type: GrantFiled: May 7, 1997Date of Patent: March 23, 1999Assignee: E. I. du Pont de Nemours and CompanyInventors: Sundar Kilnagar Venkataraman, Stuart Karl Randa, Peter Dwight Spohn
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Patent number: 5830923Abstract: Fabricated articles of fluoropolymer are foamed by heating the articles to a deformable state, pressurizing the heated article with supercritical CO.sub.2, depressurizing the pressurized heated article while still in the foamable state, whereby said CO.sub.2 foams said article, and cooling the resultant foamed article.Type: GrantFiled: April 17, 1997Date of Patent: November 3, 1998Assignee: E. I. du Pont de Nemours and CompanyInventor: Sundar Kilnagar Venkataraman
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Patent number: 5821273Abstract: Fluoropolymer resin is extrusion foamed at low temperature using carbon dioxide as the foaming agent.Type: GrantFiled: May 9, 1997Date of Patent: October 13, 1998Assignee: E. I. du Pont de Nemours and CompanyInventors: Sundar Kilnagar Venkataraman, Charles Winfield Stewart, Maurice Armand Baumann