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. 22, 2000
Filed:
Jan. 20, 1999
Rudolf Pfaendner, Rimbach, DE;
Alfred Steinmann, Praroman, DE;
Heinz Herbst, Heppenheim, DE;
Kurt Hoffmann, Weitenau-Steinen, DE;
Ciba Specialty Chemicals Corporation, Tarrytown, NY (US);
Abstract
The invention relates to a process for increasing the molecular weight of polycondensates and at the same time stabilizing them, essentially without crosslinking, which comprises heating a polyamide, a polyester, a polycarbonate or a copolymer or blend of these polymers with addition of at least one diepoxide comprising terminal epoxide groups and as a further structural element a tetramethylpiperidine radical located centrally between the epoxide groups to a temperature which is above the melting point of the polymer in the case of crystalline polycondensates or above the glass point in the case of amorphous polycondensates. The invention additionally relates to mixtures comprising the corresponding diepoxides, to their use, and to polycondensates prepared from them.