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:
Oct. 15, 1985
Filed:
Dec. 05, 1983
Michael S Cholod, Cornwells Heights, PA (US);
Rohm and Haas Company, Philadelphia, PA (US);
Abstract
A copolyester of polyethylene terephthalate and bis (4-beta hydroxy ethoxy phenyl) sulfone and a process for its preparation are provided. The copolyester has an intrinsic viscosity, glass transition temperature, and impact strength comparable to polyethylene terephthalate homopolymer but exhibits an increased crystallization time and is capable of being molded into clear articles. The process for preparing the copolyester comprises the steps of forming a polyethylene terephthalate prepolymer and polycondensing the prepolymer, preferably in the solid phase, with from about 2 to about 5 mole percent of bis (4-beta hydroxy ethoxy phenyl) sulfone in the presence of a suitable metallic catalyst system.