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:
Sep. 18, 1990
Filed:
Jan. 02, 1990
Gerald Cohn, Akron, OH (US);
The Goodyear Tire & Rubber Company, Akron, OH (US);
Abstract
There is a growing demand for high molecular weight polyester resin. For instance, the market for high molecular weight polyethylene terephthalate resin is rapidly expanding. High molecular polyethylene terephthalate resin is currently being used in vast quantities in manufacturing bottles for carbonated beverages, trays for frozen foods which can be heated in either microwave ovens or convection ovens, and in tire cord. There is a growing trend toward higher molecular weights in many applications for such polyester resins. Unfortunately, it becomes progressively more difficult and expensive to produce polyester resins having higher and higher molecular weights utilizing standard commercial polymerization techniques. This invention discloses a technique by which polyester resin having extremely high molecular weight can be prepared utilizing a very rapid solid state polymerization process. This invention more specifically discloses a process for preparing ultra-high molecular weight polyester resin which comprises: (1) dissolving a polyester prepolymer in a suitable organic solvent; (2) recovering the polyester prepolymer from the organic solvent to produce a porous, fibrous mass of the polyester prepolymer; and (3) solid state polymerizing the porous, fibrous mass at an elevated temperature to produce the ultra-high molecular weight polyester resin.