摘要:
The invention discloses a metallocene catalysed slurry polymerisation process s of ethylene in the presence of a low concentration of scavenger. This allows improving the anti-sheeting of the reactor during the polymerisation process.
摘要:
The invention discloses a metallocene catalysed slurry polymerisation process of ethylene in the presence of a low concentration of scavenger. This allows improving the anti-sheeting of the reactor during the polymerisation process.
摘要:
The resent invention discloses geo-membrane applications having good processability, high stress crack resistance, good tensile properties and high impact toughness prepared with a bimodal medium density polyethylene resin.
摘要:
This invention discloses caps and closures for carbonated drinks produced by injection moulding or by compression moulding with a bimodal high density polyethylene (HDPE) resin.
摘要:
This invention discloses caps and closures for carbonated drinks produced by injection moulding or by compression moulding with a bimodal high density polyethylene (HDPE) resin.
摘要:
Process to kill a continuous catalyzed olefin liquid phase polymerization in which the catalyst is a Ziegler-Natta or a metallocene catalyst, wherein, a predetermined amount of killing agent is injected into the reactor during at least twice the cycle time of the reactor.
摘要:
A method for the copolymerization of ethylene and a C3+ olefin copolymer in a loop reactor system and polymers formed therefrom are described herein. The method generally includes introducing an ethylene monomer, a C3+ alpha olefin comonomer and a diluent carrier liquid into a reactor system comprising at least one loop reactor; supplying at least one polymerization catalyst system to said reactor system; circulating said diluent liquid, ethylene monomer, and alpha olefin copolymer through said loop reactor while copolymerizing said ethylene and said alpha olefin monomer in the presence of said catalyst system to produce a slurry of polymer fluff particles in said diluent carrier liquid; diverting the flow of said slurry through said loop reactor into at least one settling leg connected to the loop reactor and sequentially discharging the settled polymer slurry from said at least one settling leg to withdraw said polymer slurry from said reactor system; and introducing an ethylene monomer co-feed into said loop reactor at least two spaced locations downstream of the point of introduction of ethylene comonomer and diluent in subparagraph a), said ethylene co-feed being introduced in an amount effective to reduce the variation in the ratio of ethylene monomer and comonomer within said loop reactor.
摘要:
An olefin polymerisation process carried out in the presence of an anti-fouling agent and a chromium-type catalyst or Ziegler Natta catalyst; characterised in that the anti-fouling agent comprises an anti-fouling polymer having an average molecular weight (Mw) of greater than 1000 daltons and containing: (1) one or more blocks —(CH2—CH2—O)k— where each k is in the range from 1 to 50; and (2) one or more blocks —(CH2—CH(R)—(O)n where R comprises an alkyl group having from 1 to 6 carbon atoms and each n is in the range from 1 to 50, and terminated by a R′ and a R″ end groups, wherein R′ is OH or an alkoxy having from 1 to 6 carbon atoms and R″ is H or an alkyl having from 1 to 6 carbon atoms.
摘要:
A method for controlling the injection of catalyst slurry in a polymerization reactor is described herein. The method includes the preparation of polyethylene with a solid catalyst and a hydrocarbon diluents. The method includes providing solid catalyst and a hydrocarbon diluent in one or more storage vessels such that a catalyst slurry is obtained in said vessel, transferring said catalyst slurry from said storage vessel to a mixing vessel wherein said catalyst slurry is diluted for obtaining a suitable concentration for use in a polymerization reaction, pumping said diluted catalyst slurry at a controlled flow rate from said mixing vessel to said polymerization reactor through one or more conduits, by means of a membrane pump provided in each of said conduits, and the membrane pump is controllable as a function of reactant concentration within the polymerization reactor.
摘要:
An olefin polymerisation process carried out in the presence of an anti-fouling agent and a chromium-type catalyst or Ziegler Natta catalyst; characterised in that the anti-fouling agent comprises an anti-fouling polymer having an average molecular weight (Mw) of greater than 1000 daltons and containing: (1) one or more blocks —(CH2—CH2—O)k— where each k is in the range from 1 to 50; and (2) one or more blocks —(CH2—CH(R)—(O)n− where R comprises an alkyl group having from 1 to 6 carbon atoms and each n is in the range from 1 to 50, and terminated by a R′ and a R″ end groups, wherein R′ is OH or an alkoxy having from 1 to 6 carbon atoms and R″ is H or an alkyl having from 1 to 6 carbon atoms.