The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 25, 1991
Filed:
Apr. 20, 1990
Stephen A Motika, Kutztown, PA (US);
Timothy L Pickering, Emmaus, PA (US);
Andrzej Rokicki, Alburtis, PA (US);
Beatrice K Stein, Fogelsville, PA (US);
Air Products and Chemicals, Inc., Allentown, PA (US);
Arco Chemical Company, Newtown Square, PA (US);
Mitsui Petrochemical Industries Ltd., Tokyo, JP;
Abstract
Zinc carboxylate catalysts for the copolymerization of carbon dioxide and epoxides are prepared by the reaction of zinc oxide with glutaric or adipic acid in an aprotic reaction solvent. Azeotropic distillation may be used to separate the water-solvent phase from the reaction mixture, or the catalyst may be separated from the reaction mixture by filtration and drying, generally without the need for repeated washings to remove active hydrogen atom sources. Examples of aprotic reaction solvents are toluene, dibutyl ether, anisole and ethyl benzoate.