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:
May. 22, 1990
Filed:
Jun. 12, 1989
Thomas L Guggenheim, Scotia, NY (US);
Sharon J McCormick, Clifton Park, NY (US);
Alice M Colley, Latham, NY (US);
General Electric Company, Schenectady, NY (US);
Abstract
Cyclic polyarylate oligomer compositions are prepared by the reaction of an aromatic dicarboxylic acid halide, such as isophthaloyl chloride or terephthaloyl chloride, with a water-soluble salt of a dihydroxyaromatic compound, such as bisphenol A disodium salt. Freshly prepared solutions of the halide in an organic liquid such as methylene chloride, and of the salt in water, are simultaneously introduced into an organic liquid containing a catalytic amount of at least one quaternary ammonium salt having a single alkyl group containing about 8-20 carbon atoms and having not more than 5 additional carbon atoms. The dihydroxyaromatic compound salt is employed in the amount of at least about 3% in excess of stoichiometric.