摘要:
Disclosed herein are ethylene-based polymers having a higher molecular weight component and a lower molecular weight component, and characterized by a density greater than 0.945 g/cm3, a melt index less than 1.5 g/10 min, and a ratio of high load melt index to melt index ranging from 40 to 175. These polymers have the processability of chromium-based resins, but with improved stiffness and stress crack resistance, and can be used in blow molding and other end-use applications.
摘要翻译:本文公开了具有较高分子量组分和较低分子量组分的乙烯基聚合物,其特征在于密度大于0.945g / cm 3,熔体指数小于1.5g / 10min,高负载熔体 熔体指数指数范围从40至175.这些聚合物具有铬基树脂的加工性,但具有改善的刚度和抗应力开裂性,并且可用于吹塑和其它终端应用。
摘要:
A metallocene-catalyzed polyethylene copolymer having a zero shear viscosity (ηo) of from about 1×102 Pa-s to about 5×103 Pa-s and a ratio of a z-average molecular weight to a number average molecular weight (Mz/Mn) of from about 4 to about 15, and when tested in accordance with ASTM F1249 displays a moisture vapor transmission rate of less than or equal to about 0.9 g-mil/100 in2/day. A metallocene-catalyzed polyethylene copolymer which when tested in accordance with ASTM F1249 has a moisture vapor transmission rate (MVTR) that is decreased by at least 5% when compared to an MVTR determined in accordance with ASTM F1249 of an otherwise similar metallocene-catalyzed polyethylene homopolymer.
摘要:
Disclosed herein are broad molecular weight distribution olefin polymers having densities in the 0.895 to 0.930 g/cm3 range, and with improved impact and tear resistance. These polymers can have a ratio of Mw/Mn in the 8 to 35 range, a high load melt index in the 4 to 50 range, less than about 0.008 LCB per 1000 total carbon atoms, and a reverse comonomer distribution.
摘要翻译:本文公开了具有在0.895至0.930g / cm 3范围内的密度并具有改善的耐冲击性和抗撕裂性的宽分子量分布烯烃聚合物。 这些聚合物可以具有8至35范围内的Mw / Mn比,4至50范围内的高负荷熔体指数,每1000个总碳原子小于约0.008LCB,反向共聚单体分布。
摘要:
The present invention discloses catalyst compositions employing silicon-bridged metallocene compounds with bulky substituents. Methods for making these silicon-bridged metallocene compounds and for using such compounds in catalyst compositions for the polymerization of olefins also are provided.
摘要:
Methods for controlling properties of an olefin polymer using an alcohol compound are disclosed. The MI and the HLMI of the polymer can be decreased, and the Mw and the Mz of the polymer can be increased, via the addition of the alcohol compound.
摘要:
Catalyst deactivating agents and compositions containing catalyst deactivating agents are disclosed. These catalyst deactivating agents can be used in methods of controlling polymerization reactions, methods of terminating polymerization reactions, methods of operating polymerization reactors, and methods of transitioning between catalyst systems.
摘要:
Disclosed herein are polymerization processes for the production of olefin polymers. These polymerization processes use a catalyst system containing three metallocene components, often resulting in polymers having a reverse comonomer distribution and a broad and non-bimodal molecular weight distribution.
摘要:
Methods of controlling polymerization reactions using a synergistic amount of hydrogen and an organozinc compound are disclosed. The resulting polymers have lower molecular weights and higher melt flow indices.
摘要:
Techniques are provided for catalyst preparation. A system for catalyst preparation may include an agitator disposed inside a polymerization catalyst tank and configured to mix a polymerization catalyst and a solvent to generate a polymerization catalyst solution. The system may also include a heating system coupled to the polymerization catalyst tank and configured to maintain a temperature of the polymerization catalyst solution above a threshold. The system may also include a precontactor configured to receive feed streams comprising an activator and the polymerization catalyst solution from the polymerization catalyst tank to generate a catalyst complex. The system may also include a transfer line configured to transfer the catalyst complex from an outlet of the precontactor to a reactor.
摘要:
Disclosed herein are polymerization processes for the production of olefin polymers. These polymerization processes can use a dual catalyst system containing a zirconium or hafnium based metallocene compound and a titanium based half-metallocene compound containing an indenyl group.