摘要:
Methods for preparing single and dual metallocene catalyst systems containing an activator-support are disclosed. These methods can include precontacting of the activator-support and an organoaluminum compound, as well as sequential contacting of two different metallocene compounds to form a dual metallocene catalyst system.
摘要:
A polymer reactor-blend comprising at least a first component having a polydispersity index of greater than about 20 and is present in an amount of from about 1 wt. % to about 99 wt. % based on the total weight of the polymer and a second component having a polydispersity index of less than about 20 and is present in an amount of from about 1 wt. % to about 99 wt. % based on the total weight of the polymer wherein a molecular weight distribution of the second component lies within a molecular weight distribution of the first component.
摘要:
Methods for preparing metallocene-based catalyst systems containing an activator-support are disclosed. These methods can include contacting a solid metallocene compound, an activator-support, and an organoaluminum compound, resulting in catalyst systems with increased catalytic activity as compared to catalyst systems utilizing a solution of the metallocene compound.
摘要:
Methods for the preparation of fluorided-chlorided silica-coated alumina activator-supports are disclosed. These activator-supports can be used in catalyst systems for the production of olefin-based polymers, such as polyethylene and polypropylene.
摘要:
A first embodiment which is a bimodal polymer having a weight fraction of a lower molecular weight (LMW) component ranging from about 0.25 to about 0.45, a weight fraction of a higher molecular weight (HMW) component ranging from about 0.55 to about 0.75 and a density of from about 0.931 g/cc to about 0.955 g/cc which when tested in accordance with ASTM D1003 using a 1 mil test specimen displays a haze characterized by equation: % Haze=2145=2145−2216*FractionLMW−181*a molecular weight distribution of the LMW component (MWDLMW)−932*a molecular weight distribution of the HMW component (MWDHMW)+27*(FractionLMW*MWDLMW)+1019*(FractionLMW*MWDHMW)+73*(MWDLMW*MWDHMW) wherein fraction refers to the weight fraction of the component in the polymer as a whole.
摘要:
Disclosed herein are catalyst compositions containing cyclobutylidene-bridged metallocene compounds. These catalyst compositions can be used for the polymerization of olefins.
摘要:
A crosslinked metallocene-catalyzed polyethylene copolymer having a higher molecular weight (HMW) component and lower molecular weight (LMW) component wherein the HMW component is present in an amount of from about 10 wt. % to about 30 wt. % and wherein the LMW component is present in an amount of from about 70 wt. % to about 90 wt. %.
摘要:
Methods for preparing metallocene-based catalyst systems containing an activator-support are disclosed. These methods can include contacting a solid metallocene compound, an activator-support, and an organoaluminum compound, resulting in catalyst systems with increased catalytic activity as compared to catalyst systems utilizing a solution of the metallocene compound.
摘要:
Disclosed herein are ethylene-based polymers having a melt index less than 50 g/10 min, a ratio of Mw/Mn from 4 to 20, a density from 0.90 to 0.945 g/cm3, and a substantially constant short chain branch distribution. These polymers can be produced using a dual catalyst system containing a boron bridged metallocene compound with a cyclopentadienyl group and an indenyl group, and a single atom bridged metallocene compound with a fluorenyl group.
摘要翻译:本文公开了具有熔体指数小于50g / 10min,Mw / Mn为4至20,密度为0.90至0.945g / cm 3的密度和基本恒定的短链分支分布的基于乙烯的聚合物。 这些聚合物可以使用包含具有环戊二烯基和茚基的硼桥联金属茂化合物和具有芴基的单原子桥连茂金属化合物的双重催化剂体系来制备。
摘要:
A first embodiment which is a bimodal polymer having a weight fraction of a lower molecular weight (LMW) component ranging from about 0.25 to about 0.45, a weight fraction of a higher molecular weight (HMW) component ranging from about 0.55 to about 0.75 and a density of from about 0.931 g/cc to about 0.955 g/cc which when tested in accordance with ASTM D1003 using a 1 mil test specimen displays a haze characterized by equation: % Haze=2145−2216*FractionLMW−181*a molecular weight distribution of the LMW component (MWDLMW)−932*a molecular weight distribution of the HMW component(MWDHMW)+27*(FractionLMW*MWDLMW)+1019*(FractionLMW*MWDHMW)+73*(MWDLMW*MWDHMW) wherein fraction refers to the weight fraction of the component in the polymer as a whole.