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:
Jun. 10, 2014
Filed:
Mar. 04, 2008
Larry W. Leininger, Akron, PA (US);
Dong Tian, Lancaster, PA (US);
Larry W. Leininger, Akron, PA (US);
Dong Tian, Lancaster, PA (US);
AWI Licensing Company, Wilmington, DE (US);
Abstract
A process for producing higher molecular weight polyester includes heating a polyester to form a melt, and applying and maintaining a vacuum of between about 5 mm and about 85 mm of mercury to the melt while passing bubbles of gas through the melt until molecular weight has increased. The process may involve esterification of a diacid component and a diol component at elevated temperature. After the acid functional groups have essentially reacted, a vacuum of about 5 mm of mercury or less was applied and excess diol stripped off during transesterification, thereby increasing molecular weight.