Patent ID: 7964677
Filing Date: 2011-06-21
Classification: C08F,Y10S

Abstract:
1. A method of changing from a polymerization using a first catalyst to a polymerization using a second catalyst which is incompatible with the first catalyst in a gas-phase reactor, said method comprising: a) stopping the polymerization reaction using the first catalyst; b) flushing the reactor under polymerization conditions with at least one deactivating agent comprising a volatile component selected from an organic compound or a mixture of organic compounds comprising at least one functional group selected from the group consisting of —OR, —NR2, —SR, ═O, and ═S, wherein R is hydrogen or a C c) introducing the second catalyst into the reactor; and d) continuing the polymerization using the second catalyst, wherein the nonvolatile component comprises at least a polymeric amine, a polymeric amide, a polyamine, a polyamine copolymer or a polysulfone copolymer.