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:
Dec. 02, 1997
Filed:
Dec. 13, 1996
Duane B Priddy, Jr, Krefeld, DE;
Burkhard Kohler, Leverkusen, DE;
Robert J Kumpf, Pittsburgh, PA (US);
Harald Pielartzik, Krefeld, DE;
Bayer Corporation, Pittsburgh, PA (US);
Bayer Aktiengesellschaft, Leverkusen, DE;
Abstract
A process is disclosed whereby a polymeric resin (containing ester and/or carbonate bonds) is readily converted into a resin having a modified molecular structure. Accordingly, a polycyclic carbonate (a monomer or oligomer) is transesterified with the polymer resin in the melt, preferably upon extrusion, optionally in the presence of a catalyst. Significantly, the cyclic carbonates are, by the inventive process, inserted into the structure of the polymer, effecting branching of the molecular structure, a branching which manifests itself in the modified properties of the resin.