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:
Feb. 09, 1999
Filed:
Aug. 29, 1997
Applicant:
Inventors:
Assignee:
Zimmer Aktiengesellschaft, , DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08J / ; C08G / ;
U.S. Cl.
CPC ...
521 485 ; 528279 ; 528280 ; 528281 ; 528283 ; 528285 ; 528482 ; 528491 ; 528495 ; 528501 ; 528503 ;
Abstract
The invention comprises a method for synthesizing polyethylene terephthalate from waste polyethylene terephthalate by cleavage with ethylene glycol and separation of bis(hydroxyethylene) terephthalate from the cleavage mixture with a specific temperature program, recrystallization from water, and esterification and polycondensation with the addition of terephthalic acid. The invention further comprises a method for synthesis of polyethylene naphthalate from waste polyethylene naphthalate in a similar manner.