Abstract:
A propylene polymer composition comprising: a) from 40 wt% to 80 wt% of a propylene 1-hexene copolymer containing from 5.5 to 9.0% by weight, of 1-hexene derived units having a Melt Flow Rate (MFR, measured according to ASTM D 1238, 230°C/2.16 kg, i.e. at 230°C, with a load of 2.16 kg) from 3.5 to 12.0 g/10 min; b) from 20 wt% to 60 wt% of a propylene ethylene copolymer containing from 1.5 wt% to 6.5 wt% of ethylene derived units, a having a Melt Flow Rate (MFR, measured according to ASTM D 1238, 230°C/2.16 kg, i.e. at 230°C, with a load of 2.16 kg) from 3.5 to 12.0 g/10 min.
Abstract translation:丙烯聚合物组合物,其包含:a)40重量%至80重量%的含5.5至9.0重量%的1-己烯衍生单元的丙烯1-己烯共聚物,所述单元具有熔体流动 速率(MFR,根据ASTM D 1238,230℃/ 2.16kg,即在230℃,2.16kg的负荷下测量)为3.5-12.0g / 10min; b)20重量%至60重量%的含有1.5重量%至6.5重量%的乙烯衍生单元的丙烯乙烯共聚物,其熔体流动速率(MFR,根据ASTM D 1238,230℃/ 2.16 kg,即在230℃,2.16kg的负载下)为3.5-12.0g / 10min。 p>
Abstract:
A gas-phase process for the homo or copolymerization of propylene with other olefins, carried out in the presence of a catalyst system comprising: (a) a solid catalyst component comprising Mg, Ti, halogen, an electron donor selected from 1.3-diethers and an olefin polymer in a specific amount; (b) an aluminum alkyl compound and (c) an external electron donor compound selected from specific classes; said components (a) and (c) being employed in amounts such that the Al/(ED) molar ratio ranges from 2 to 200. The process is capable to give polypropylene product having good morphological properties, high stereoregularity, and capable to show self- extinguishing properties such that the negative effects caused by the fine catalyst particle polymerization can be selectively solved or mitigated.
Abstract:
Feeding a supported antistatic compound that does not comprise a transition- metal-based catalyst component to an olefin polymerization reactor allows avoiding the formation of polymer agglomerates in the reactor while at the same time minimizing negative effects on catalyst yield.
Abstract:
A process for the preparation of ethylene polymers comprising polymerizing ethylene, optionally with one or more α-olefin comonomers, in the presence of: (i) a solid catalyst component comprising titanium, magnesium, halogen and optionally an internal electron-donor compound, (ii) an aluminum alkyl compound, and (iii) an antistatic compound selected among the hydroxyesters with at least two free hydroxyl groups, wherein the weight ratio of aluminum alkyl compound to solid catalyst component is higher than 0.80 and the weight ratio of antistatic compound to aluminum alkyl compound is higher than 0.10.
Abstract:
A polymerization process for preparing heterophasic propylene copolymers in two or more gas-phase reactors connected in series, in the presence of a polymerization catalyst comprising a catalytic component based on a titanium compound supported on magnesium halide, the process comprising the following steps: - contacting said catalytic component with an organo-Aluminum compound at a temperature from 5°C to 30°C and a weight ratio propylene/(catalytic component) ranging from 0 to 2.0; - prepolymerizing the catalyst from A) with propylene, optionally in the presence of an inert hydrocarbon solvent; - polymerizing propylene, optionally with an another -olefin comonomer in an amount lower than 15% by weight, to prepare a semicrystalline polymer component; - successively copolymerizing two or more alpha-olefin comonomers C 2 -C 10 to prepare one or more olefin copolymers having a solubility in xylene higher than 15% by weight; the process being characterized in that the bulk density of the semi-crystalline component of step C) is adjusted at a value lower than 0.40 g/cm 3 .
Abstract:
A fluid is fed into a polymer bed of a fluidized bed gas phase polymerization reactor by introducing it into the polymer bed through a distributor protruding into the fluidized bed zone of the reactor and terminating with a discharge end positioned so that the following equation is fulfilled: d/D > 0.002 wherein d is the distance of the distributor's discharge end from the wall of the reactor, and D is the diameter of the reactor in the fluidized bed zone.
Abstract:
A gas-phase process for the homo or copolymerization of olefins carried out in the presence of a catalyst system formed by a contacting in a liquid hydrocarbon and in the presence of hydrogen (a) a solid catalyst component comprising a Ti, Mg and C1, and optionally an internal electron donor compound, (b) an aluminum alkyl compound and optionally (c) an external donor compound.
Abstract:
Process for the gas-phase polymerization of one or more alpha-olefins in the presence of a catalyst system, the process comprising: contacting in a continuous way one or more of said alpha-olefins with said catalyst system in a prepolymerization reactor, wherein the reaction is carried out in a liquid medium at a temperature ranging from 23° to 500C; feeding in continuous the prepolymer obtained in step a) into a gas-phase reactor having interconnected polymerization zones, where the growing polymer particles flow upward through a first polymerization zone (riser) under fast fluidization or transport conditions, leave said riser and enter a second polymerization zone (downcomer) through which they flow downward under the action of gravity, leave said downcomer and are reintroduced into said riser; wherein the prepolymer obtained from step a) is continuously fed at a section of said riser characterized by an upwardly gas velocity higher than 3.0 m/s.
Abstract:
Feeding a supported antistatic compound that does not comprise a transition-metal-based catalyst component to an olefin polymerization reactor allows avoiding the formation of polymer agglomerates in the reactor while at the same time minimizing negative effects on catalyst yield.