Abstract: The present invention relates to compositions comprising at least one fluoroolefin and an effective amount of stabilizer that may be at least one phenol or a mixture of at least one phenol with other stabilizers. The stabilized compositions may be useful in cooling apparatus, such as refrigeration, air-conditioning, chillers, and heat pumps, as well as in applications as foam blowing agents, solvents, aerosol propellants, fire extinguishants, and sterilants.
Type:
Application
Filed:
June 25, 2013
Publication date:
October 31, 2013
Inventors:
VELLIYUR NOTT MALLIKARJUNA RAO, Mario Joseph Nappa, Barbara Haviland Minor, Thomas Joseph Leck, Nandini C. Mouli
Abstract: The present invention relates to compositions comprising at least one fluoroolefin and an effective amount of stabilizer that may be a terpene, terpenoid or fullerene; or a mixture of a terpene, terpenoid or fullerene with other stabilizers. The stabilized compositions may be useful in cooling apparatus, such as refrigeration, air-conditioning, chillers, and heat pumps, as well as in applications as foam blowing agents, solvents, aerosol propellants, fire extinguishants, and sterilants.
Type:
Application
Filed:
December 14, 2011
Publication date:
April 12, 2012
Applicant:
E. I. DU PONT DE NEMOURS AND COMPANY
Inventors:
JON LEE HOWELL, Velliyur Nott Mallikarjuna Rao, Thomas J. Leck, Barbara Haviland Minor, Mario Joseph Nappa, Nandini C. Mouli, Ekaterina N. Swearingen, Andrew Edward Feiring
Abstract: Certain substituted phenolic compounds when used with or without 1,2-epoxides as the sole stabilizer components are very effective in stabilizing n-propyl bromide (NPB). In a standard commercially important 60° C. stability test, representative substituted phenolic compounds used pursuant to this invention, can enable NPB to pass the test even though present at levels of about 50 ppm (wt/wt) or less in NPB containing no other stabilizer additive component. In fact, amounts as low as 1 ppm have been found effective with various substituted phenolic compounds. In addition, it has been found that one of the preferred stabilizers of this invention—2,6-di-tert-butyl-p-cresol—even though higher boiling than NPB, left inconsequential amounts of residue at least throughout the range of 1 to 30 ppm (wt/wt). Also, it has been found that certain other preferred stabilizers of this invention can provide synergistically improved stability in passing the 60° C.
Abstract: (1) At least one nitro compound and (2) at least one member selected from the group consisting of an aromatic hydrocarbon and an alicyclic unsaturated hydrocarbon are added to 1,1,1,2,3,3-hexafluoropropane (HFC236ea) or 1,1,1,3,3-pentafluoropropane (HFC245fa). Optionally, (3) at least one member selected from the group consisting of an aliphatic unsaturated hydrocarbon, an epoxy compound, an ether compound, a phenol compound, an ester compound and a cyclic compound is further added. As a result, HFC236ea and HFC245fa have remarkably improved stability at any stages and in any states during storage and use of HFC236ea or HFC245fa and during use of the foamed product.
Abstract: An improved process for producing hydrofluorocarbons and hydrochlorofluorocarbons by reacting anhydrous hydrogen fluoride in the vapor phase and in the presence of a fluorination catalyst with an admixture of perchloroethylene and a phenolic inhibitor. The phenolic component is effective to inhibit the formation of an oxidation product in the perchloroethylene while not substantially degrading the fluorination catalyst during the fluorination process. In another embodiment, substantially all of any oxidation inhibitor is removed from the perchloroethylene in-line prior to reacting the hydrogen fluoride with the perchloroethylene.
Abstract: Dibromostyrene has a marked tendency to polymerize on storage. The induction period can be lengthened with the use of a stabilizing quantity of n-propylgallate. The induction period can be markedly prolonged when the gallate ester is admixed with phenothiazine, N,N,N',N'-tetramethyl-p-phenylenediamine, or 4-tert-butyl catechol.