摘要:
Polyethylene modified by using radical initiators such as oxygen and peroxides sometimes has a yellow color which may be reduced or eliminated by incorporating additives such as polyethylene glycol, and/or neutralizing species such as alkali metal stearates, particularly calcium stearate, and zinc oxide.
摘要:
Disclosed is a bimodal Ziegler-Natta catalyzed polyethylene, having a density of from 0.930 glee to 0.960 glee, and a molecular weight distribution of from 10 to 25, wherein an article formed therefrom has a PENT of at least 1500. Also disclosed is a method of preparing a tubular article including obtaining a bimodal polyethylene having a density of from 0.930 glee to 0.960 Wee and a molecular weight distribution of from 10 to 25, and processing the polyethylene under conditions where a specific energy input (SET) is less than 300 kW.h/ton, and wherein the article has a PENT of at least 1500. Further disclosed is a method for controlling the degradation of polyethylene including polymerizing ethylene monomer, recovering polyethylene, extruding the polyethylene, and controlling the degradation of polyethylene by measuring the SEI to the extruder and adjusting throughput and/or gear suction pressure keep SEI less than 300 kW.h/ton, and forming an article.
摘要翻译:公开了一种双峰型齐格勒 - 纳塔催化聚乙烯,其密度为0.930gle-0.960glee,分子量分布为10-25,其中由其形成的制品具有至少为1500的PENT。还公开了一种方法 制备管状制品,包括获得密度为0.930glee至0.960ee的分子量分布为10至25的双峰聚乙烯,并且在比能量输入(SET)小于300kW的条件下处理聚乙烯 h / ton,并且其中制品具有至少1500的PENT。还公开了一种控制聚乙烯降解的方法,包括聚合乙烯单体,回收聚乙烯,挤出聚乙烯,并通过测量SEI来控制聚乙烯的降解 到挤出机并调节产量和/或齿轮吸入压力使SEI小于300kW.h / ton,并形成物品。
摘要:
Disclosed is a bimodal Ziegler-Natta catalyzed polyethylene, having a density of from 0.930 g/cc to 0.960 g/cc, and a molecular weight distribution of from 10 to 25, wherein an article formed therefrom has a PENT of at least 1500. Also disclosed is a method of preparing a tubular article including obtaining a bimodal polyethylene having a density of from 0.930 g/cc to 0.960 g/cc and a molecular weight distribution of from 10 to 25, and processing the polyethylene under conditions where a specific energy input (SEI) is less than 300 kW·h/ton, and wherein the article has a PENT of at least 1500. Further disclosed is a method for controlling the degradation of polyethylene including polymerizing ethylene monomer, recovering polyethylene, extruding the polyethylene, and controlling the degradation of polyethylene by measuring the SEI to the extruder and adjusting throughput and/or gear suction pressure keep SEI less than 300 kW·h/ton, and forming an article.
摘要:
Disclosed is a bimodal Ziegler-Natta catalyzed polyethylene, having a density of from 0.930 g/cc to 0.960 g/cc, and a molecular weight distribution of from 10 to 25, wherein an article formed therefrom has a PENT of at least 1500. Also disclosed is a method of preparing a tubular article including obtaining a bimodal polyethylene having a density of from 0.930 g/cc to 0.960 g/cc and a molecular weight distribution of from 10 to 25, and processing the polyethylene under conditions where a specific energy input (SEI) is less than 300 kW·h/ton, and wherein the article has a PENT of at least 1500. Further disclosed is a method for controlling the degradation of polyethylene including polymerizing ethylene monomer, recovering polyethylene, extruding the polyethylene, and controlling the degradation of polyethylene by measuring the SEI to the extruder and adjusting throughput and/or gear suction pressure keep SEI less than 300 kW·h/ton, and forming an article.
摘要:
Disclosed is a bimodal Ziegler-Natta catalyzed polyethylene, having a density of from 0.930 g/cc to 0.960 g/cc, and a molecular weight distribution of from 10 to 25, wherein an article formed therefrom has a PENT of at least 1500. Also disclosed is a method of preparing a tubular article including obtaining a bimodal polyethylene having a density of from 0.930 g/cc to 0.960 g/cc and a molecular weight distribution of from 10 to 25, and processing the polyethylene under conditions where a specific energy input (SEI) is less than 300 kW·h/ton, and wherein the article has a PENT of at least 1500. Further disclosed is a method for controlling the degradation of polyethylene including polymerizing ethylene monomer, recovering polyethylene, extruding the polyethylene, and controlling the degradation of polyethylene by measuring the SEI to the extruder and adjusting throughput and/or gear suction pressure keep SEI less than 300 kW·h/ton, and forming an article.
摘要:
Polyethylene modified by using radical initiators such as oxygen and peroxides sometimes has a yellow color which may be reduced or eliminated by incorporating additives such as polyethylene glycol, and/or neutralizing species such as alkali metal stearates, particularly calcium stearate, and zinc oxide.
摘要:
Propylene polymerization processes, polymers and films formed therefrom are described herein. The propylene polymerization processes generally include contacting propylene and an amount of ethylene with a first metallocene catalyst and a second metallocene catalyst within a polymerization reaction vessel to form a propylene based polymer, wherein the amount is an amount effective to form the propylene based polymer including from about 2 wt. % to about 6 wt. % ethylene, the second metallocene catalyst is capable of incorporating a greater amount of ethylene into the propylene based polymer than the first metallocene catalyst and wherein the first metallocene catalyst is capable of forming a propylene/ethylene random copolymer exhibiting a melting temperature that is greater than that of a propylene/ethylene random copolymer formed from the second metallocene catalyst.
摘要:
Polymerization processes and polymers formed therefrom are described herein. The polymerization processes generally include contacting ethylene and propylene with a multi-component catalyst composition including a first catalyst component including a chromium oxide based catalyst and a second catalyst component selected from metallocene and Ziegler-Natta catalysts within a polymerization reaction vessel to form a random copolymer, wherein the second catalyst component exhibits a higher comonomer response than the first catalyst component.
摘要:
Blown films and processes of forming the same are described herein. The blown films generally include high density polyethylene exhibiting a molecular weight distribution of from about 1.5 to about 8.0 and a density of from 0.94 g/cc to less than 0.96 g/cc.
摘要:
Supported catalyst systems, methods of forming the supported catalyst systems and polymerization processes including the supported catalyst systems are described herein. The methods generally include providing an inorganic support composition, wherein the inorganic support composition comprises aluminum, fluorine and silica and contacting the inorganic support composition with a transition metal compound to form a supported catalyst system, wherein the transition metal compound is represented by the formula [L]mM[A]n; wherein L is a bulky ligand, A is a leaving group, M is a transition metal and m and n are such that a total ligand valency corresponds to the transition metal valency. The methods further include contacting the inorganic support composition, the transition metal compound, the supported catalyst system or combinations thereof with at least one compound represented by the formula XRn, wherein X is selected from Group 12 to 13 metals, lanthanide series metals or combinations thereof and each R is independently selected from alkyls, alkoxys, aryls, aryloxys, halogens, hydrides, Group 1 or 2 metals, organic nitrogen compounds, organic phosphorous compounds and combinations thereof and n is from 2 to 5.
摘要翻译:本文描述了负载型催化剂体系,形成负载型催化剂体系的方法和包括负载型催化剂体系的聚合方法。 所述方法通常包括提供无机载体组合物,其中无机载体组合物包含铝,氟和二氧化硅,并使无机载体组合物与过渡金属化合物接触以形成负载型催化剂体系,其中过渡金属化合物由式[ M] [A] n < 其中L是大体积配体,A是离去基团,M是过渡金属,m和n使总配体的化合价对应于过渡金属的价态。 所述方法还包括使无机载体组合物,过渡金属化合物,负载型催化剂体系或其组合与至少一种由式XR n n表示的化合物接触,其中X选自第12至13族 金属,镧系金属或其组合,每个R独立地选自烷基,烷氧基,芳基,芳氧基,卤素,氢化物,第1或2族金属,有机氮化合物,有机磷化合物及其组合,n为2至5 。