摘要:
A method for the copolymerization of ethylene and a C3+ olefin in a loop reactor and polymers formed therefrom are described herein. The method generally includes introducing an ethylene monomer, a C3+ olefin and a diluent carrier liquid into a loop reactor. A catalyst system can be supplied to said loop reactor. The diluent liquid, ethylene monomer, and C3+ olefin can be circulated through said loop reactor, while copolymerizing said ethylene and C3+ olefin in the presence of said catalyst system to produce a slurry. The slurry can be diverted into a settling leg, and sequentially discharged therefrom and withdrawn from said loop reactor. An ethylene monomer co-feed can be introduced into said loop reactor at spaced locations downstream of the ethylene and diluent. The ethylene co-feed can be introduced in an amount effective to reduce the variation in the ratio of ethylene and C3+ olefin.
摘要:
The present invention relates to an apparatus and process for polymerizing olefins. One embodiment comprises polymerizing at least one monomer in a first loop reactor in the presence of a catalyst to produce a first polyolefin fraction. A portion of the first polyolefin fraction is transferred to a second loop reactor, connected in series with the first loop reactor. The process further comprises polymerizing in the second loop reactor at least one monomer in the presence of a catalyst to produce a second polyolefin fraction in addition to the first polyolefin fraction. The combination of the first and second polyolefin fractions can produce a polymer resin fluff having bimodal molecular weight distribution.
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:
This invention relates to the synthesis of polycarbonates prepared from carbonate monomers derived from the biomass in the presence of a system comprising an organometallic transfer agent and alcohol. It also relates to the polymers resulting from these cyclic compounds.
摘要:
A polyethylene resin comprising from 35 to 49 wt. % of a first polyethylene fraction of high molecular weight and from 51 to 65 wt. % of a second polyethylene fraction of low molecular weight, the first polyethylene having a density of up to 0.930 g/cm3, and an HLMI of less than 0.6 g/10 min and the second polyethylene fraction comprising a high density polyethylene having a density of at least 0.969 g/cm3 and an MI2 of greater than 10 g/10 min, and the polyethylene resin, having a density of greater than 0.946 g/cm3, an HLMI of from 1 to 100 g/10 min, a dynamical viscosity, measured at 0.01 radians/second, greater than 200,000 Pa.s and a ratio of the dynamical viscosities measured at, respectively 0.01 and 1 radians/second greater than 8.
摘要翻译:一种聚乙烯树脂,其包含35至49wt。 %的高分子量的第一聚乙烯级分和51至65wt。 %的低分子量的第二聚乙烯级分,第一聚乙烯的密度高达0.930g / cm 3,HLMI小于0.6g / 10min,第二聚乙烯级分包含 密度为0.969g / cm 3以上且MI 2以上大于10g / 10min的高密度聚乙烯和聚乙烯树脂具有密度 大于0.946g / cm 3,HLMI为1至100g / 10min,以0.01弧度/秒测量的动力学粘度大于200,000Pa.s,并且 动态粘度分别为0.01和1弧度/秒,大于8。
摘要:
A metallocene compound having the general formula: CpAXMQ1Q2Cp′A′X′M′Q1′Q2′ wherein Cp and Cp′ are each independently a substituted or unsubstituted cyclopentadienyl moiety; M and M′ are each independently a metal chosen from Group IV B transition metals and vanadium, and coordinate to Cp and Cp′ respectively; X and X′ are each independently a substituted or unsubstituted Group VA or VIA heteroatom and coordinate to M and M′ respectively; A and A′ are bridging groups between Cp and X and between Cp′ and X′ respectively and are independently chosen from —SiR′2—O—SiR′2—, —SinR′m—, —CnR′m— and —CR′2—SiR′2—CR′2—SiR′2—, in which each R′ is independently H or hydrocarbyl having 1 to 20 carbon atoms, n is an integer in the range 1 to 4 and m=2n; each Q1, Q2 and Q1′ and Q2′ is independently a coordinating group which is hydrogen, halogen or hydrocarbyl having 1 to 20 carbon atoms and each of Q1 and Q1′ is coordinated to both M and M′.
摘要:
This invention relates to the polymerisation of five-, six- or seven-membered cyclic carbonates by ring-opening polymerisation in the presence of a system comprising a metal salt such as triflate, triflimidate, acetylacetonate or carboxylate and an alcohol.
摘要:
A polyethylene resin comprising from 35 to 49 wt. % of a first polyethylene fraction of high molecular weight and from 51 to 65 wt. % of a second polyethylene fraction of low molecular weight, the first polyethylene having a density of up to 0.930 g/cm3, and an HLMI of less than 0.6 g/10 min and the second polyethylene fraction comprising a high density polyethylene having a density of at least 0.969 g/cm3 and an MI2 of greater than 10 g/10 min, and the polyethylene resin, having a density of greater than 0.946 g/cm3, an HLMI of from 1 to 100 g/10 min, a dynamical viscosity, measured at 0.01 radians/second, greater than 200,000 Pa·s and a ratio of the dynamical viscosities measured at, respectively 0.01 and 1 radians/second greater than 8.
摘要:
This invention relates to the synthesis of polycarbonates prepared from carbonate monomers derived from the biomass in the presence of a system comprising an organometallic transfer agent and alcohol. It also relates to the polymers resulting from these cyclic compounds.
摘要:
A propylene polymerisation process carried out in the presence of an anti-fouling agent; characterised in that the anti-fouling agent comprises an anti-fouling polymer 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, and the anti-fouling polymer is solvated in a solvent comprising cyclohexane when added to the polymerisation medium.