E.i. Dupont De Nemours and Company

Conocophillips Company

E. I. Du Pont De Nemours

Munirpallam Appadorai Subramanian

Allen Capron Sievert

Velliyur Nott Mallikarjuna Rao

H David Rosenfeld

Jagannatha Gopalakrishnan

V N Rao

Arthur W Sleight

Shekhar Subramoney

James J Krajewski

Dong Li

Tao He

Mario Joseph Nappa

Leo E Manzer

John D Bolt

Velliyur Nott Rao

V N Mallikarjuna Rao

Kamel M Makar

Wenchun Chao

Nyrissa S Rogado

David Richard Corbin

Brian C Auman

Barry Asher Mahler

John Donald Summers

Thomas Eugene Dueber

Ajoy P Raje

Edwin J Warwas

Olga P Ionkina

Vn Mallikarjuna Rao

Timothy C Duzick

Sekhar Subramoney

Uma Chowdhry

Rao Vn Mallikarjuna

Richard B Flippen

Thomas R Askew

David H Rosenfeld

Water absorption resistant polyimide/epoxy-based compositions, like pastes (or solutions), are particularly useful to make electronic screen-printable materials and electronic components. A group of hydrophobic epoxies (and soluble polyimides) was discovered to be particularly resistant to moisture absorption. The polyimide/epoxy pastes made with these epoxies (and these polyimides) may optionally contain thermal crosslinking agents, adhesion promoting agents, blocked isocyanates, and other inorganic fillers. The polyimide/epoxy pastes of the present invention can have a glass transition temperature greater than 250&#xb0; C., a water absorption factor of less than 2%, and a positive solubility measurement.

Composition of polyimide and sterically-hindered hydrophobic epoxy

The present invention provides an indium-doped CoSbskutterudite composition in which some Co on the cubic lattice structure may be replaced with one or more members of the group consisting of Fe, Ni, Ru, Rh, Pd, Ir and Pt; some Sb on the planar rings may be replaced by one or more members of the group consisting of Si, Ga, Ge and Sn; and a second dopant atom is selected from a member of the group consisting of Ca, Sc, Zn, Sr, Y, Pd, Ag, Cd, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu. The composition is useful as a thermoelectric material. In preferred embodiments, the composition has a figure of merit greater than 1.0. The present invention also provides a process for the production of the composition, and thermoelectric devices using the composition.

High performance thermoelectric materials and their method of preparation

A crystalline alpha-chromium oxide where from about 0.05 atom % to about 2 atom % of the chromium atoms in the alpha-chromium oxide lattice are substituted by nickel atoms, and optionally, additional chromium atoms in the alpha-chromium oxide lattice are substituted by trivalent cobalt atoms (provided that the total amount of the nickel atoms and the trivalent cobalt atoms in the alpha-chromium oxide lattice is no more than 6 atom %) is disclosed. Also disclosed is a chromium-containing catalyst composition comprising as a chromium-containing component the crystalline substituted alpha-chromium oxide; and a method for preparing a composition comprising the crystalline substituted alpha-chromium oxide. The method comprises (a) co-precipitating a solid by adding ammonium hydroxide to an aqueous solution of a soluble divalent nickel salt, a soluble trivalent chromium salt, and optionally, a soluble divalent or trivalent cobalt salt, that contains at least three moles of nitrate per mole of chromium in the solution, has a nickel concentration of from about 0.05 mole % to about 2 mole % of the total of nickel, chromium, and cobalt in the solution, and has a combined concentration of nickel and cobalt of no more than 6 mole % of the total of nickel, chromium, and cobalt in the solution; and after at least three moles of ammonium per mole of chromium has been added to the solution; (b) collecting the co-precipitated solid formed in (a); (c) drying the collected solid; and (d) calcining the dried solid. Also disclosed is a chromium-containing catalyst composition comprising a chromium-containing component prepared by treating said crystalline substituted alpha-chromium oxide with a fluorinating agent; and a process for changing the fluorine distribution (i.e., content and/or arrangement) in a hydrocarbon or halogenated hydrocarbon in the presence of a catalyst. The process involves using as the catalyst a composition comprising the crystalline substituted alpha-chromium oxide and/or the treated substituted alpha-chromium oxide.

Nickel-substituted and mixed nickel-and cobalt-substituted chromium oxide compositions, their preparation, and their use as catalysts and catalysts precursors

Provided are compositions containing 20 to 50% by volume of a nitride or carbide of a group IV metal, a polymer, and 1 to 9% by volume of an allotrope of carbon. The compositions are useful in manufacturing resistors with low temperature coefficients of resistivity.

Low temperature coefficient of resistivity polymeric resistors based on metal carbides and nitrides

The present invention relates to a process for the preparation of thermoelectric compositions of the formula InCOSb(0&#x3c;x&#x3c;1), with a figure of merit greater than 1.0 and a composition made by that process.

Method of preparation for the high performance thermoelectric material indium-cobalt-antimony

This invention provides novel thermoelectric compounds comprising:

Figure of merit in Ytterbium-Aluminum-Manganese intermetallic thermoelectric and method of preparation

This invention provides the three novel La,Fe, La,Cr and Sm,Fe substituted barium titanate solid solution ferroelectric compositions with the formula BaLnTiMOwherein when Ln is La, M is Fe or Cr, when Ln is Sm, M is Fe and x is from about 0.02 to about 0.06 and mixtures thereof, the novel La,Fe substituted barium strontium titanate solid solution ferroelectric compositions with the formula (BaSr)LaTiFeOwherein y is greater than zero and less than about 0.6 and x is from about 0.01 to about 0.06 and the novel La,Al substituted barium strontium titanate solid solution ferroelectric compositions with the formula (BaSr)LaTiAlOwhereindenotes a vacancy, y is greater than zero and less than about 0.6, a is from about 0.01 to about 0.06 and x is from 0.02 to about 0.10 with the proviso that x is greater than or equal to a. These low loss tunable ferroelectric compositions are especially useful in tunable microwave thin film devices which fall into three types: interdigital and trilayer capacitors, coplanar waveguides and microstrips.

Substituted barium titanate and barium strontium titanate ferroelectric compositions

A crystalline alpha-chromium oxide where from about 0.05 atom % to about 6 atom % of the chromium atoms in the alpha-chromium oxide lattice are replaced by trivalent cobalt (Co) atoms is disclosed. Also disclosed is a chromium-containing catalyst composition comprising as a chromium-containing component the crystalline cobalt-substituted alpha-chromium oxide; and a method for preparing a composition comprising the crystalline cobalt-substituted alpha-chromium oxide. The method involves (a) co-precipitating a solid by adding ammonium hydroxide to an aqueous solution of a soluble cobalt salt and a soluble trivalent chromium salt that contains at least three moles of nitrate per mole of chromium in the solution and has a cobalt concentration of from about 0.05 mole % to about 6 mole % of the total concentration of cobalt and chromium in the solution; and after at least three moles E of ammonium per mole of chromium in the solution has been added to the solution, (b) collecting the co-precipitated solid formed in (a); (c) drying the collected solid; and (d) calcining the dried solid. Also disclosed is a chromium-containing catalyst composition comprising a chromium-containing component prepared by treating the crystalline cobalt-substituted alpha-chromium oxide with a fluorinating agent; and a process for changing the fluorine distribution (i.e., content and/or arrangement) in a hydrocarbon or halogenated hydrocarbon in the presence of a catalyst. The process involves using as the catalyst a composition comprising the crystalline cobalt-substituted alpha-chromium oxide and/or the treated cobalt-substituted alpha-chromium oxide.

Cobalt-substituted chromium oxide compositions, their preparation, and their use as catalysts and catalyst precursors

A process for the preparation of 2-chloro-1,1,1,3,3,3-heptafluoropropane is disclosed which involves (a) contacting a mixture comprising hydrogen fluoride, chlorine, and at least one starting material selected from the group consisting of halopropenes of the formula CX3CCI&#x2550;CX2 and halopropanes of the formula the CX3CCIYCX3, wherein each X is independently F or Cl, and Y is H, Cl or F (provided that the number of X and Y which are F totals no more than six) with a chlorofluorination catalyst in a reaction zone to produce a product mixture comprising CF3CCIFCF3, HCI, HF. and underfluorinated halogenated hydrocarbon intermediates. The process is characterized by said chlorofluorination catalyst comprising at least one chromium-containing component selected from (i) a crystalline alpha-chromium oxide where at least 0.05 atom % of the chromium atoms in the alpha-chromium oxide lattice are replaced by nickel, trivalent cobalt or both nickel and trivalent cobalt, provided that no more than 2 atom % of the chromium atoms in the alpha-chromium oxide lattice are replaced by nickel and that the total amount of chromium atoms in the alpha-chromium oxide lattice that are replaced by nickel and trivalent cobalt is no more than 6 atom %, and (ii) a fluorinated crystalline oxide of (i). Also disclosed is a process for the manufacture of a mixture of HFC-227ea and hexafluoropropene by reacting a starting mixture comprising CFC-217ba and hydrogen in the vapor phase at an elevated temperature, optionally in the presence of a hydrogenation catalyst. This process involves preparing the CFC-217ba by the process described above.

Processes for the preparation of 2-chloro-1,1,1,2,3,3,3-heptafluoropropane, hexafluoropropene and 1,1,1,2,3,3,3-heptafluoropropane

This invention provides the three novel La,Fe, La,Cr and Sm,Fe substituted barium titanate solid solution ferroelectric compositions with the formula BaLnTiMOwherein when Ln is La, M is Fe or Cr, when Ln is Sm, M is Fe and x is from about 0.02 to about 0.06 and mixtures thereof, the novel La,Fe substituted barium strontium titanate solid solution ferroelectric compositions with the formula (BaSr)LaTiFeOwherein y is greater than zero and less than about 0.6 and x is from about 0.01 to about 0.06 and the novel La,Al substituted barium strontium titanate solid solution ferroelectric compositions with the formula (BaSr)LaTiAl}Owherein } denotes a vacancy, y is greater than zero and less than about 0.6, a is from about 0.01 to about 0.06 and x is from 0.02 to about 0.10 with the proviso that x is greater than or equal to a. These low loss tunable ferroelectric compositions are especially useful in tunable microwave thin film devices which fall into three types: interdigital and trilayer capacitors, coplanar waveguides and microstrips.

A process for the preparation of pentafluoroethane is disclosed which involves contacting a mixture comprising hydrogen fluoride and at least one starting material selected from haloethanes of the formula CXCHXand haloethanes of the formula CX&#x2550;CX, where each X is independently selected from the group consisting of F and Cl (provided that no more than four of X are F), with a fluorination catalyst in a reaction zone to produce a product mixture comprising HF, HCl, pentafluoroethane, underfluorinated halogenated hydrocarbon intermediates and less than 0.2 mole percent chloropentafluoroethane based on the total moles of halogenated hydrocarbons in the product mixture. The process is characterized by the fluorination catalyst comprising (i) a crystalline cobalt-substituted alpha-chromium oxide where from about 0.05 atom % to about 6 atom % of the chromium atoms in the alpha-chromium oxide lattice are replaced by trivalent cobalt (Co) and/or (ii) a fluorinated crystalline oxide of (i).

Process for the preparation of 1,1,1,2,2-pentafluoroethane

This invention provides the three novel La,Fe, La,Cr and Sm,Fe substituted barium titanate solid solution ferroelectric compositions with the formula BaLnTiMOwherein when Ln is La, M is Fe or Cr, when Ln is Sm, M is Fe and x is from about 0.02 to about 0.06 and mixtures thereof, the novel La,Fe substituted barium strontium titanate solid solution ferroelectric compositions with the formula (BaSr)LaTiFeOwherein y is greater than zero and less than about 0.6 and x is from about 0.01 to about 0.06 and the novel La,Al substituted barium strontium titanate solid solution ferroelectric compositions with the formula (BaSr)LaTiAlOwherein denotes a vacancy, y is greater than zero and less than about 0.6, a is from about 0.01 to about 0.06 and x is from 0.02 to about 0.10 with the proviso that x is greater than or equal to a. These low loss tunable ferroelectric compositions are especially useful in tunable microwave thin film devices which fall into three types: interdigital and trilayer capacitors, coplanar waveguides and microstrips.

This invention provides compositions of the formula EuCuMOwherein M is Ge, Ti, Sn or mixtures thereof. These compositions have high dielectric constant and low loss over a frequency range of from 1 kHz to 1 MHz.

Divalent europium-containing compositions

Compositions having the nominal formulaBiSrCaCuO

Superconducting bismuth-strontium-calcium-copper oxide compositions and process for manufacture

This invention provides compositions of the formula Cu Ta MO wherein M is Al, Ga, Fe, Cr, Sc or mixtures thereof. These compositions have high dielectric constant and low loss over a frequency range of from 1 kHz to 1 MHz.

Growing community of inventors

Kennett Square, PA, United States of America

Munirpallam Appadorai Subramanian