Organic compounds -- part of the class 532-570 series – Organic compounds – Heterocyclic carbon compounds containing a hetero ring...
Reexamination Certificate
2005-08-18
2009-06-09
Saeed, Kamal A (Department: 1626)
Organic compounds -- part of the class 532-570 series
Organic compounds
Heterocyclic carbon compounds containing a hetero ring...
C548S101000, C556S013000
Reexamination Certificate
active
07544800
ABSTRACT:
A method is provided for carrying out depolymerization of a polymer containing electrophilic linkages in the presence of a catalyst and a nucleophilic reagent, wherein production of undesirable byproducts resulting from polymer degradation is minimized. The reaction can be carried out at a temperature of 80° C. or less, and generally involves the use of an organic, nonmetallic catalyst, thereby ensuring that the depolymerization product(s) are substantially free of metal contaminants. In an exemplary depolymerization method, the catalyst is a carbene compound such as an N-heterocyclic carbene, or is a precursor to a carbene compound. The method provides an important alternative to current recycling techniques such as those used in the degradation of polyesters, polyamides, and the like.
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Hedrick James Lupton
Nyce Gregory Walker
Waymouth Robert M.
International Business Machines - Corporation
Mintz Levin Cohn Ferris Glovsky and Popeo PC
Rutenberg Isaac M.
Saeed Kamal A
The Board of Trustees of the Leland Stanford University
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