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:
Nov. 29, 1983
Filed:
Sep. 07, 1982
Richard R Smith, Cuyahoga Falls, OH (US);
Mellis M Kelley, Akron, OH (US);
The Goodyear Tire & Rubber Company, Akron, OH (US);
Abstract
This invention relates to polyethylene isophthalate (PEI) and copolymers thereof having low cyclic dimer content and process for making same. The invention provides a process for making PEI using protonic acid catalysts which result in a polymer having lower amounts of ring dimer of ethylene isophthalate than has heretofore been known. Strong protonic acids such as sulfuric or phosphoric are utilized as polymerization catalysts to thereby lower the amount of cyclic dimerization which occurs during the polymerization process. Polymers so produced are of a high purity and have reduced manufacturing costs due both to a smaller amount of material being lost as cyclic dimer and because of lower processing costs associated with cleaning cyclic dimer from the processing equipment.