Patents by Inventor Dibakar Dhara
Dibakar Dhara 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: 8865833Abstract: A method of preparing a polycarbonate nanocomposite comprising forming a reactant mixture comprising a nanomaterial, a solvent, a dihydroxy compound and an activated carbonate; and polymerizing the dihydroxy compound and the activated carbonate in the presence of the solvent to form the polycarbonate nanocomposite is disclosed. Also disclosed are polycarbonate nanocomposites prepared in accordance with this method, and thermoplastic compositions comprising the polycarbonate nanocomposites. Also disclosed are polycarbonate compositions comprising the nanomaterial.Type: GrantFiled: July 14, 2010Date of Patent: October 21, 2014Assignee: Sabic Global Technologies B.V.Inventors: Amit Biswas, Dibakar Dhara, Raja Krishnamurthy, Edward Kung, Parnasree Maiti, Roopali Rai, Vaidyanath Ramakrishnan, Vitthal Abaso Sawant, Rajashekhar Shiddappa Totad, Sandeep Tyagi
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Patent number: 8389648Abstract: A composition, comprising, based on the total weight of the polymer components in the composition, 1 to 40 wt. % of an aromatic polycarbonate, 30 to 98.8 wt. % of a polysiloxane-polycarbonate block copolymer, and 0.1 to 10 wt. % of a polysiloxane-polyimide block copolymer comprising more than 20 wt. % polysiloxane blocks, based on the total weight of the polysiloxane-polyimide copolymer. The compositions provide articles with low haze, high luminous transmittance, and good hydro-aging properties. The articles can further be formulated to have excellent flame retardance, particularly when KSS is used.Type: GrantFiled: August 2, 2011Date of Patent: March 5, 2013Assignee: Sabic Innovative Plastics IP B.V.Inventors: Purushotham Adoni, Dibakar Dhara, Sriramakrishna Maruvada, Roopali Rai, Veeraraghavan Srinivasan
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Publication number: 20110288214Abstract: A composition, comprising, based on the total weight of the polymer components in the composition, 1 to 40 wt. % of an aromatic polycarbonate, 30 to 98.8 wt. % of a polysiloxane-polycarbonate block copolymer, and 0.1 to 10 wt. % of a polysiloxane-polyimide block copolymer comprising more than 20 wt. % polysiloxane blocks, based on the total weight of the polysiloxane-polyimide copolymer. The compositions provide articles with low haze, high luminous transmittance, and good hydro-aging properties. The articles can further be formulated to have excellent flame retardance, particularly when KSS is used.Type: ApplicationFiled: August 2, 2011Publication date: November 24, 2011Applicant: SABIC INNOVATIVE PLASTICS IP B.V.Inventors: Purushotham ADONI, Dibakar DHARA, Sriramakrishna MARUVADA, Roopali RAI, Veeraraghavan SRINIVASAN
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Patent number: 7994254Abstract: A composition, comprising, based on the total weight of the polymer components in the composition, 1 to 40 wt. % of an aromatic polycarbonate, 30 to 98.8 wt. % of a polysiloxane-polycarbonate block copolymer, and 0.1 to 10 wt. % of a polysiloxane-polyimide block copolymer comprising more than 20 wt. % polysiloxane blocks, based on the total weight of the polysiloxane-polyimide copolymer. The compositions provide articles with low haze, high luminous transmittance, and good hydro-aging properties. The articles can further be formulated to have excellent flame retardance, particularly when KSS is used.Type: GrantFiled: June 20, 2008Date of Patent: August 9, 2011Assignee: Sabic Innovative Plastics IP B.V.Inventors: Veeraraghavan Srinivasan, Roopali Rai, Dibakar Dhara, Sriramakrishna Maruvada, Purushotham Adoni
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Patent number: 7888447Abstract: A polycarbonate-polysiloxane copolymer comprising structural units of the formula: wherein each R1, R2, and R3 is independently the same or different monovalent C1-12 should this be C1-C13 like in the document? hydrocarbon group, G comprises a monovalent C6-1000 poly(oxyalkyl) group, each R4 and R5 taken together is independently the same or different divalent C3-30 hydrocarbon linking group wherein R4 is a C1-28 hydrocarbon and R5 is a C2-29 aliphatic group, a is 0 or greater, and b is one or greater; and structural units of the formula: wherein each R is independently the same or different C6-60 divalent hydrocarbon group, and at least 60% of the R groups comprise aromatic moieties.Type: GrantFiled: March 29, 2007Date of Patent: February 15, 2011Assignee: Sabic Innovative Plastics IP B.V.Inventors: Dibakar Dhara, Katherine Glasgow, Brian D. Mullen, Vikram Kumar, Mark D. Leatherman, Suresh Rajaraman, Anubhav Saxena
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Publication number: 20100280176Abstract: A method of preparing a polycarbonate nanocomposite comprising forming a reactant mixture comprising a nanomaterial, a solvent, a dihydroxy compound and an activated carbonate; and polymerizing the dihydroxy compound and the activated carbonate in the presence of the solvent to form the polycarbonate nanocomposite is disclosed. Also disclosed are polycarbonate nanocomposites prepared in accordance with this method, and thermoplastic compositions comprising the polycarbonate nanocomposites. Also disclosed are polycarbonate compositions comprising the nanomaterial.Type: ApplicationFiled: July 14, 2010Publication date: November 4, 2010Applicant: SABIC INNOVATIVE PLASTICS IP B.V.Inventors: Amit Biswas, Dibakar Dhara, Raja Krishnamurthy, Edward Kung, Parnasree Maiti, Roopali Rai, Vaidyanath Ramakrishnan, Vitthal Abaso Sawant, Rajashekhar Shiddappa Totad, Sandeep Tyagi
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Patent number: 7807772Abstract: Disclosed herein is a copolymer comprising isosorbide carbonate units and a polysiloxane block, wherein the copolymer comprises greater than or equal to 50 mol % isosorbide carbonate units.Type: GrantFiled: December 23, 2009Date of Patent: October 5, 2010Assignee: Sabic Innovative Plastics IP B.V.Inventors: Gautam Chatterjee, Dibakar Dhara, Muthuvijayan Jegathesan
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Patent number: 7718755Abstract: The above-described and other deficiencies of the art are met by a method of making a polycarbonate polymer comprising isosorbide carbonate units, comprising melt reacting a dihydroxy compound comprising an isosorbide of the general formula (2a): and an activated carbonate, in the presence of a catalyst consisting essentially of a sodium salt capable of providing a hydroxide ion, wherein the polycarbonate polymer comprises greater than or equal to 50 mol % isosorbide carbonate units, and wherein the polycarbonate polymer has a Mw of greater than or equal to about 40,000 g/mol as determined by gel-permeation chromatography relative to polystyrene standards. Polycarbonates comprising the isosorbide carbonate unit, including isosorbide homopolycarbonate and an isosorbide-based polyester-polycarbonate, are also disclosed, as are a thermoplastic composition and an article including the isosorbide-based polycarbonate polymer.Type: GrantFiled: October 18, 2007Date of Patent: May 18, 2010Assignee: SABIC Innovative Plastics IP B.V.Inventors: Guatam Chatterjee, Dibakar Dhara, Muthuvijayan Jegathesan
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Publication number: 20100120993Abstract: Disclosed herein is a copolymer comprising isosorbide carbonate units and a polysiloxane block, wherein the copolymer comprises greater than or equal to 50 mol % isosorbide carbonate units.Type: ApplicationFiled: December 23, 2009Publication date: May 13, 2010Applicant: SABIC Innovative Plastics, IP B.V.Inventors: Gautam Chatterjee, Dibakar Dhara, Muthuvijayan Jegathesan
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Patent number: 7687557Abstract: Polycarbonate compositions having an aromatic polycarbonate resin with 90% or greater fluoroalkylene carbonate end-groups are formed from a partially fluorinated alcohol or a partially fluorinated polymeric alcohol, and a bisphenol and a carbonate source using melt or interfacial polymerization methods. Copolymers and blends with a variety of other bisphenols and other thermoplastics are also described. The polycarbonate compositions show high water contact angles, fluorine enrichment on the surface layer of molded articles, and good flame retardant properties and are useful in a variety of applications including medical, automotive, telecommunication and weatherable applications.Type: GrantFiled: January 11, 2008Date of Patent: March 30, 2010Assignee: SABIC Innovative Plastics IP B.V.Inventors: Gary Charles Davis, Dibakar Dhara, Brian D. Mullen, Joshua James Stone
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Patent number: 7649073Abstract: Disclosed herein is a polycarbonate copolymer comprising A) a structure derived from a dihydroxy alkylene oxide compound selected from the group consisting of formula (1a) and formula (1b): H-(E-X)l—OH??(1a) H-(E-X-E)l-OH??(1b) wherein E and X are different and each and independently are selected from the group consisting of formula (2a) and formula (2b): —(OCH2CH2)m—??(2a) —(OCHRCH2)n—??(2b) wherein R is a C1-8 alkyl group; l, m, and n are integers greater than or equal to 1; and wherein the weight average molecular weight of the total amount of the structures corresponding to formula (2b) in the copolymer is between 100 and 2,000 g/mol; and B) a structure derived from a dihydroxy aromatic compound, wherein the weight percentages are based on the total weight of the structures of A) and B).Type: GrantFiled: June 15, 2007Date of Patent: January 19, 2010Assignee: SABIC Innovative Plastics IP B.V.Inventors: Gary C. Davis, Dibakar Dhara, Sarah Elizabeth Genovese, Katherine Glasgow, Gautam Madan, Patrick J. McCloskey, Yohana Perez de Diego, William D. Richards
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Patent number: 7642315Abstract: Disclosed herein is a polycarbonate copolymer comprising A) a structure derived from a dihydroxy alkylene oxide compound selected from the group consisting of formula (1a) and formula (1b): H-(E-X)l—OH??(1a) H-(E-X-E)l-OH??(1b) wherein E and X are different and each and independently are selected from the group consisting of formula (2a) and formula (2b): —(OCH2CH2)m—??(2a) —(OCHRCH2)n—??(2b) wherein R is a C1-8 alkyl group; l, m, and n are integers greater than or equal to 1; and wherein the weight average molecular weight of the total amount of the structures corresponding to formula (2b) in the copolymer is between 100 and 2,000 g/mol; and B) a structure derived from a dihydroxy aromatic compound, wherein the weight percentages are based on the total weight of the structures of A) and B).Type: GrantFiled: June 15, 2007Date of Patent: January 5, 2010Assignee: SABIC Innovative Plastics IP B.V.Inventors: Gary C. Davis, Dibakar Dhara, Sarah Elizabeth Genovese, Katherine Glasgow, Jennifer Kübel, Gautam Madan, Patrick J. McCloskey, William D. Richards
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Patent number: 7638091Abstract: A method comprising treating an article with steam, wherein the article comprises a composition comprising an amount of a polysiloxane-polycarbonate copolymer effective to provide thermal and hydrolytic stability to the article for at least 15 cycles, wherein each cycle comprises 20 minutes of contact with steam at 100° C., at atmospheric pressure. The articles are of utility in a wide variety of applications such as food service and medical applications.Type: GrantFiled: July 2, 2004Date of Patent: December 29, 2009Assignee: SABIC Innovative Plastics IP B. V.Inventors: Gautam Chatterjee, Dibakar Dhara, Katherine Glasgow, Antoinette van Bennekom, Jos van den Bogerd, Adam Zerda
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Publication number: 20090318629Abstract: A composition, comprising, based on the total weight of the polymer components in the composition, 1 to 40 wt. % of an aromatic polycarbonate, 30 to 98.8 wt. % of a polysiloxane-polycarbonate block copolymer, and 0.1 to 10 wt. % of a polysiloxane-polyimide block copolymer comprising more than 20 wt. % polysiloxane blocks, based on the total weight of the polysiloxane-polyimide copolymer. The compositions provide articles with low haze, high luminous transmittance, and good hydro-aging properties. The articles can further be formulated to have excellent flame retardance, particularly when KSS is used.Type: ApplicationFiled: June 20, 2008Publication date: December 24, 2009Applicant: SABIC INNOVATIVE PLASTICS IP B.V.Inventors: Purushotham ADONI, Dibakar DHARA, Sriramakrishna MARUVADA, Roopali RAI, Veeraraghavan SRINIVASAN
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Publication number: 20090105444Abstract: The above-described and other deficiencies of the art are met by a method of making a polycarbonate polymer comprising isosorbide carbonate units, comprising melt reacting a dihydroxy compound comprising an isosorbide of the general formula (2a): and an activated carbonate, in the presence of a catalyst consisting essentially of a sodium salt capable of providing a hydroxide ion, wherein the polycarbonate polymer comprises greater than or equal to 50 mol % isosorbide carbonate units, and wherein the polycarbonate polymer has a Mw of greater than or equal to about 40,000 g/mol as determined by gel-permeation chromatography relative to polystyrene standards. Polycarbonates comprising the isosorbide carbonate unit, including isosorbide homopolycarbonate and an isosorbide-based polyester-polycarbonate, are also disclosed, as are a thermoplastic composition and an article including the isosorbide-based polycarbonate polymer.Type: ApplicationFiled: October 18, 2007Publication date: April 23, 2009Inventors: Gautam Chatterjee, Dibakar Dhara, Muthuvijayan Jegathesan
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Publication number: 20090088509Abstract: A copolycarbonate composition is provided comprising a blend of a polycarbonate-polysiloxane copolymer and a terephthalate polymer. The blend has a combination of good melt volume rate, good fatigue resistance, and high ductility at low temperatures.Type: ApplicationFiled: September 28, 2007Publication date: April 2, 2009Applicant: SABIC Innovative Plastics IP BVInventors: Purushotham Adoni, Dibakar Dhara, Vandita Pai-Paranjape, Ajay K. Taraiya
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Publication number: 20080312374Abstract: Disclosed herein is a polycarbonate copolymer comprising A) a structure derived from a dihydroxy alkylene oxide compound selected from the group consisting of formula (1a) and formula (1b): H-(E-X)l—OH ??(1a) H-(E-X-E)l-OH ??(1b) wherein E and X are different and each and independently are selected from the group consisting of formula (2a) and formula (2b): —(OCH2CH2)m— ??(2a) —(OCHRCH2)n— ??(2b) wherein R is a C1-8 alkyl group; l, m, and n are integers greater than or equal to 1; and wherein the weight average molecular weight of the total amount of the structures corresponding to formula (2b) in the copolymer is between 100 and 2,000 g/mol; and B) a structure derived from a dihydroxy aromatic compound, wherein the weight percentages are based on the total weight of the structures of A) and B).Type: ApplicationFiled: June 15, 2007Publication date: December 18, 2008Applicant: GENERAL ELECTRIC COMPANYInventors: Gary C. Davis, Dibakar Dhara, Sarah Elizabeth Genovese, Katherine Glasgow, Gautam Madan, Patrick J. McCloskey, Yohana Perez de Diego, William D. Richards
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Publication number: 20080312373Abstract: Disclosed herein is a polycarbonate copolymer comprising A) a structure derived from a dihydroxy alkylene oxide compound selected from the group consisting of formula (1a) and formula (1b): H-(E-X)l—OH ??(1a) H-(E-X-E)l-OH ??(1b) wherein E and X are different and each and independently are selected from the group consisting of formula (2a) and formula (2b): —(OCH2CH2)m— ??(2a) —(OCHRCH2)n— ??(2b) wherein R is a C1-8 alkyl group; l, m, and n are integers greater than or equal to 1; and wherein the weight average molecular weight of the total amount of the structures corresponding to formula (2b) in the copolymer is between 100 and 2,000 g/mol; and B) a structure derived from a dihydroxy aromatic compound, wherein the weight percentages are based on the total weight of the structures of A) and B).Type: ApplicationFiled: June 15, 2007Publication date: December 18, 2008Applicant: GENERAL ELECTRIC COMPANYInventors: Gary C. Davis, Dibakar Dhara, Sarah Elizabeth Genovese, Katherine Glasgow, Jennifer Kubel, Gautam Madan, Patrick J. McCloskey, William D. Richards
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Publication number: 20080242804Abstract: A polycarbonate-polysiloxane copolymer comprising structural units of the formula: wherein each R1, R2, and R3 is independently the same or different monovalent C1-12 should this be C1-C13 like in the document! hydrocarbon group, G comprises a monovalent C6-1000 poly(oxyalkyl) group, each R4 and R5 taken together is independently the same or different divalent C3-30 hydrocarbon linking group wherein R4 is a C1-28 hydrocarbon and R5 is a C2-29 aliphatic group, a is 0 or greater, and b is one or greater; and structural units of the formula: wherein each R is independently the same or different C6-60 divalent hydrocarbon group, and at least 60% of the R groups comprise aromatic moieties.Type: ApplicationFiled: March 29, 2007Publication date: October 2, 2008Applicant: GENERAL ELECTRIC COMPANYInventors: Dibakar Dhara, Katherine Glasgow, Brian D. Mullen
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Patent number: 7374718Abstract: A composition comprising an aromatic carbonate polymer and an amount of at least one solid cyclic aliphatic alcohol stabilizing compound sufficient to inhibit yellowing of the composition upon exposure to a sterilizing radiation, wherein said stabilizing compound is selected from the group consisting of 2,2,4,4-tetramethylcyclobutane-1,3-diol, 1,4-cyclohexanediol, and wherein said stabilizing compound is present in said composition in an amount of at least about 0.2 parts by weight per 100 parts by weight of said aromatic carbonate polymers.Type: GrantFiled: October 6, 2005Date of Patent: May 20, 2008Assignee: General Electric CompanyInventors: Dibakar Dhara, Katherine C. Glasgow, Vikram Kumar