摘要:
Processes for transitioning among polymerization catalyst systems, preferably catalyst systems that are incompatible with each other. In particular, the processes relate to transitioning from olefin polymerizations utilizing metallocene catalyst systems to olefin polymerizations utilizing traditional Ziegler-Natta catalyst systems.
摘要:
Processes for transitioning among polymerization catalyst systems, preferably catalyst systems that are incompatible with each other. In particular, the processes relate to transitioning from olefin polymerizations utilizing metallocene catalyst systems to olefin polymerizations utilizing traditional Ziegler-Natta catalyst systems.
摘要:
The invention relates to a method for evaluating the condition of a fluidized bed reactor by examining the condition of the reactor wall. Specifically, the invention relates to a method for measuring static in the reactor using a static probe that is located at the distributor plate and comprises a distributor plate cap. The invention also relates to methods of determining a static level using a radio frequency (rf). The static measurements are provided to indicate or predict major continuity disturbances in the fluidized bed gas phase reactor.
摘要:
The present invention relates to a method and apparatus for controlling static charges in a fluidized bed olefin polymerization reactor. Static charges which develop in the polymer products are measured and, if they fall outside a predetermined range, static charge control agents are introduced into the reactor. By controlling the static charges in the reactor, sheeting and drooling can be controlled.
摘要:
The present invention relates to a gas phase process for polymerizing one or more hydrocarbon monomer(s) in the presence of a catalyst system and a fluorinated hydrocarbon, where the fluorinated hydrocarbon is present at a partial pressure of 6.9 to 348 kPa in the reactor and the reactor temperature is from 30 to 120° C.
摘要:
This invention relates to a process comprising contacting an polymerization reactor effluent with a fluorinated hydrocarbon and thereafter recovering olefin polymer, where the fluorinated hydrocarbon is present at 5 volume % to 99 volume % based upon the volume of the effluent and the fluorinated hydrocarbon, and where the polymerization is a continuous polymerization of at least 75 mole % of hydrocarbon monomers, based upon the total moles of monomer present in the reactor.
摘要:
The present invention relates to a gas phase process for polymerizing one or more hydrocarbon monomer(s) in the presence of a catalyst system and a fluorinated hydrocarbon, where the fluorinated hydrocarbon is present at a partial pressure of 6.9 to 348 kPa in the reactor and the reactor temperature is from 30 to 120° C.
摘要:
This invention relates to a continuous process to prepare olefin impact copolymers comprising producing a semi-crystalline olefin polymer in a first reactor and then transferring the reactor contents to a second reactor where a low crystallinity olefin polymer is produced in the presence of the semi-crystalline polymer, where a fluorinated hydrocarbon is present in the polymerization medium of the first reactor, the second reactor or both reactors.
摘要:
The present invention relates to a method and apparatus for controlling static charges in a fluidized bed olefin polymerization reactor. Static charges which develop in the polymer products are measured and, if they fall outside a predetermined range, static charge control agents are introduced into the reactor. By controlling the static charges in the reactor, sheeting and drooling can be controlled.
摘要:
This invention relates to a process to polymerize olefins comprising contacting a catalyst or catalyst system with olefin(s) in the presence of a fluorocarbon at a temperature above the onset melting point of the polymer.This invention also relates to a solution process to polymerize olefins comprising contacting a catalyst or catalyst system with olefin(s) in the presence of a fluorocarbon at a temperature above the onset melting point of the polymer.