催化剂及助剂

新乙烯淤浆聚合催化剂成功运行由北京化工研究院独立研制的BCE乙烯淤浆聚合催化剂在扬子石化淤浆高密度聚乙烯装置上成功运行,主要用于生产管材树脂,产品质量优异,全部达到企业产品标准。BCE催化剂是北化院继BCH催化剂后研制的新一代高活性乙烯淤     

中国专利

包含茂金属生产的树脂和铬生产的树脂的聚乙烯共混物的制备方法本发明涉及的均质聚乙烯的制备方法包括:a)在茂金属催化剂存在下,在反应器中生产第一聚乙烯树脂,该聚乙烯树脂具有0.942~0.970 g/cm3的密度和0.5~150.0 g/10 min的熔体流动速率(MFR),其中,MFR按照ASTM D 1238—2010在190℃,21.6kg的负荷条件下测试,密度按GB/T 1505—2010测试。b)在铬催化剂存在下,在反应器中单独生产第二聚乙烯树脂。c)将第一聚乙烯树脂和第二聚乙烯树脂物理共混生产均质聚乙烯,该均质聚乙烯至少包含质量分数为25%的第一聚乙烯树脂。     

乙烯淤浆聚合BCE催化剂通过中国石化鉴定

2008年1月10日,由中国石油化工股份有限公司（简称中国石化）科技开发部组织召开了“乙烯淤浆聚合BCE催化剂工业放大制备及工业应用”的鉴定会,与会专家一致认为,BCE催化剂活性高,共聚性能和氢调性能好,所制备的聚合物堆密度高,粒径分布窄,细粉含量少,其性能优于国际同类催化剂。     

脂肪醇在聚烯烃催化剂中的应用

Z-N催化剂在聚烯烃装置中占有很大的应用比例,而利用脂肪醇改性后的催化剂广泛应用于三井化学株式会社CX工艺、巴塞尔Hostalen工艺生产高密度聚乙烯。介绍了PZ/RZ、JM-1、BCH、BCE、XY-H、SLC-SP2等催化剂的制备方法,并对脂肪醇在催化剂中的作用及含量进行了说明。     

气相聚乙烯BCG催化剂的工业应用

介绍了BCG催化剂在Unipol气相法聚乙烯装置上的工业应用。工业试用表明，BCG催化剂的流动性能、氢调和共聚合性能良好，活性较高，综合性能优良；树脂性能测试表明，用BCG催化剂生产的薄膜级线型低密度聚乙烯树脂的加工性能良好，产品物理、机械性能达到优级品标准。     

宽峰聚乙烯／蒙脱土纳米复合材料的制备

利用2种不同的方法制备了2种氢调敏感性不同的蒙脱土／氯化镁／四氯化钛（MMT／MgCl2／TiCl4）催化剂,利用这2种催化剂及其混配催化剂,通过原位聚合法,制备出一系列宽峰聚乙烯纳米复合材料,采用X_射线衍射仪（XRD）、凝胶色谱测试分析（GPC）及力学性能测试等方法对催化剂及聚合产物进行分析,结果表明,2种催化剂以及按照不同比例混合的混配催化剂均表现出较高的聚合活性,XRD测试结果表明,蒙脱土片层在乙烯聚合过程中发生了插层及剥离,以单片层或几层共存的形式分散于聚乙烯基质中;用混配催化剂可制得宽峰聚乙烯纳米复合材料,Mw／Mn=7．23,并且聚合物的堆积密度达到工业生产的标准,宽峰聚乙烯纳米复合材料的综合力学性能较工业产品5000S及工业上应用的管材料有很大的提高。     

纯净水瓶盖专用树脂HDPE 5603JP的开发

采用了BCE催化剂,利用小试装置考察了氢气和1-丁烯对该催化剂催化乙烯聚合的影响。并将该催化剂用在淤浆法聚乙烯生产装置上,生产了纯净水瓶盖专用高密度聚乙烯(HDPE)5603JP。测试结果表明,该树脂具有适宜的密度、熔体流动速率、力学性能和卫生性能,适合生产瓶盖。生产的瓶盖产品各项性能也与国外原料生产的瓶盖产品相当。     

北京化工研究院新型PE催化剂在泰国试用成功

由北京化工研究院研发的聚乙烯BCE催化剂在泰国BPE公司125kt·a^-1三井聚乙烯装置成功试用,此次试用成功为BCE催化剂进入泰国市场奠定了基础。     

北化院PE催化剂在泰国BPE公司试用成功

2013年8月,由中国石油化工股份有限公司北京化工研究院研发的聚乙烯催化剂BCE在泰国BPE公司125kt/a聚乙烯装置上试用成功,BPE公司对试验结果表示满意。此次试用为BCE催化剂进入泰国市场奠定了基础。本次试验采用BCE催化剂共生产聚乙烯(7000F)逾1 kt。产品质量符合既定指标。聚合物粒径分布窄,细粉含量少。     

环保型聚乙烯-丙烯酸吸水树脂的合成

利用聚乙烯（PE）回收料和具有亲水性基团的丙烯酸（AA）,通过反相乳液聚合法接枝共聚合成了环保型PE—AA吸水树脂。探讨了原料配比、NaOH溶液用量、反应温度、反应时间、引发剂种类及其用量、交联剂用量等因素对吸水树脂吸水率的影响。实验结果表明,在m（AA）：m（PE）为8：1、AA用量32g、质量分数25％的NaOH溶液40mL、反应温度70℃、反应时间3h、引发剂（过硫酸铵／亚硫酸氢钠）6mL、交联剂（环氧氯丙烷）2mL的条件下,制备的PE—AA吸水树脂的吸水率为455．3g／g。PE、聚丙烯、聚苯乙烯与AA接枝共聚所得吸水树脂中,PE—AA吸水树脂的性能较优。     

Z-N催化剂生产宽/双峰MWD聚乙烯的研究进展

介绍了Ziegler-Natta(Z-N)催化剂在单反应器中生产宽,双峰相对分子质量分布(MWD)聚乙烯(PE)的最新研究进展,概括了Z-N催化剂制备宽／双峰MWDPE的主要方法及特点,即传统的Ti系催化体系生产的双峰PE的MWD较窄,改进的Ti-V双金属催化体系活性高,可以调节MWD,但反应操作难度大。通过加入不同的配合物,调节并改进PE的MWD,取得了较好的实验结果。宽/双峰MWDPE的生产和开发是PE工业发展的一个重要方向。     

一段反应法生产双峰聚乙烯催化剂研究进展

作为生产双峰聚乙烯的一种方法,一段反应法是在一个反应釜中进行反应,并最终得到含有高相对分子质量和低相对分子质量组分的混合聚乙烯树脂,这是一种新型的合成方法,与过去的分段式反应法相比,在实际应用中对现有的装置改造的规模较小,操作较容易且成本较低,因此,日益受到人们的关注,具有良好的发展前景。重点对一段反应法进行了阐述,同时对它制备的催化剂的方法进行了综述,主要包括4种类型:复合类型、双金属负载类型、单组分类型以及双载体类型等。本文介绍了各类技术的优缺点及各种催化剂的工业化应用前景。     

双峰分子量分布聚乙烯的研究进展

双峰聚乙烯是目前用途很广、市场前景很好的一种通用树脂。国内外双峰分子量分布聚乙烯研究取得了很大进展，重点领域为双峰分子量分布聚乙烯制备工艺和催化剂的研究。双峰聚乙烯具有优异的性能，为进一步开拓市场，我国应着力开展这方面的研究开发生产工作。     

聚乙烯管材专用树脂生产技术开发

利用淤浆法串联聚合丁艺产品具有相对分子质量双峰分布的特点,结合管材专用树脂的物性及微观结构特点,确定了由第一聚合釜均聚合生产低相对分子质量产品、第二聚合釜共聚合生产高相对分子质量产品的生产工艺。通过对2个聚合釜聚合温度、聚合压力、共聚单体的加入量和氢气与乙烯比等工艺参数的分析和调整．得到适合高级别管材专用树脂的最佳生产条件,产品的最小要求强度超过8MPa,达到管材专用树脂PE80的等级。     

双峰相对分子质量分布聚乙烯的生产现状及进展

综述了国内外双峰相对分子质量分布聚乙烯(PE)的工艺技术和催化剂的研究进展。着重介绍了以Hostalen、 Borealis、Mitsui、UnipolⅡ等为代表的串联反应釜聚合工艺,并对相对分子质量分布对材料加工性能的影响进行了讨论。最后简要介绍了双峰PE产品的应用领域和新产品开发情况。     

双峰PE树脂的结构与性能

研究了国产催化剂和进口催化剂分别生产的同一牌号双峰聚乙烯树脂的结晶性能和流变行为,表征了其相对分子质量及其分布.2种树脂的力学性能差异可归结为其相对分子质量及其分布和结晶性能的不同:国产催化剂生产的树脂要达到同进口催化剂生产的树脂一样的流变行为,模头温度必须达到200℃以上.     

Molecular mass characteristics of polyethylene produced with supported vanadium‐magnesium catalysts

Highly active supported vanadium‐magnesium catalysts (VMC) produce polyethylene (PE) with broad and bimodal molecular mass distribution (MMD) in comparison with the famous titanium‐magnesium catalysts (TMC). The effect of hydrogen as an efficient chain‐transfer agent on the MMD of PE has been studied. Increasing hydrogen concentration causes a considerable broadening of MMD of PE due to the shift of the low molecular weight peak on the MMD curve. At the same time, the high molecular weight shoulder stays at the same position even at high hydrogen concentration. This means that VMC contain two types of active centre. One type is very reactive in the chain‐transfer reaction with hydrogen. These centres produce low molecular weight PE in polymerization in the presence of hydrogen. The other type of active centre is not active in chain transfer with hydrogen. These centres produce high molecular weight PE ((1–3) × 10⁶) and hydrogen does not affect the position of the high molecular weight shoulder. MMD data were used to analyze the kinetics of the chain‐transfer reaction with hydrogen and to calculate the rate constants of this reaction. Copyright © 2005 Society of Chemical Industry     

Heterogeneous catalyst mixtures for the polymerization of ethylene

Heterogeneous cocatalysts, catalysts, and catalyst mixtures for the polymerization of ethylene were prepared applying “fumed silica” and mesoporous MCM-41 support materials and zirconocene dichloride, titanocene dichloride, and a bis(arylimino)pyridine iron complex as catalyst precursors. The catalyst mixtures produced polyethylenes which exhibit the properties of two single polymers. Polyethylenes with the desired bimodal molecular weight distributions could be obtained with a series of ternary Zr/Ti/Fe catalysts. The ability of the zirconium and titanium species to copolymerize short-chain 1-olefins produced by the iron centers (“in situ” copolymerization) is useful for the production of copolymers from only one monomer (ethylene).     

Bimodal polypropylene through binary metallocene catalytic systems: comparison between hybrid and mixed heterogeneous catalysts

Polypropylene with wider or bimodal molecular weight distribution is required for numerous applications since low molecular weight chains improve processability and high molecular weight fraction is required to get good mechanical properties. There are several routes to achieve a bimodal resin but the use of a binary catalytic system seems to be the most attractive, particularly with metallocenes combination. From a previous work two metallocenes were selected because they lead to polypropylenes with average molecular weights that differ in one order of magnitude. Two types of binary systems have been investigated, hybrid catalysts (two metallocenes loaded on the same support) and physical mixtures (two independent supported metallocenes that are introduced to the reactor and start the polymerization together), using different ratios, i.e., 25–75, 50–50, 75–25, at three reaction temperatures, i.e., 30, 50 and 70 °C. Most of the binary catalytic systems lead to bimodal molecular weight distributions. Polypropylenes produced by mixed catalysts are greatly influenced by the most active catalyst, while in PP coming from hybrid catalysts, as there is a strong interaction between both metallocenes, each one contributes according to its presence in the hybrid catalyst. Therefore, properties of obtained bimodal polypropylenes are quite influenced by the ratio between both metallocenes.     

Preparation of ultra‐high‐molecular‐weight polyethylene and its morphological study with a heterogeneous Ziegler–Natta catalyst

Ultra‐high‐molecular‐weight polyethylene (PE) with viscosity‐average molecular weight (M_v) of 3.1 × 10⁶ to 5.2 × 10⁶ was prepared with a heterogeneous Ziegler–Natta MgCl₂ (ethoxide type)/TiCl₄/triethylaluminum catalyst system under controlled conditions. The optimum activity of the catalyst was obtained at a [Al]/[Ti] molar ratio of 61 : 1 and a polymerization temperature of 60°C, whereas the activity of the catalyst increased with monomer pressure and decreased with hydrogen concentration. The titanium content of the catalyst was 2.4 wt %. The rate/time profile of the catalyst was a decay type with a short acceleration period. M_v of the PE obtained decreased with increasing hydrogen concentration and polymerization temperature. The effect of stirrer speeds from 100 to 400 rpm did not so much affect the catalyst activity; however, dramatic effects were observed on the morphology of the polymer particles obtained. A stirrer speed of 200 rpm produced PE with a uniform globulelike morphological growth on the polymer particles. The particle size distributions of the polymer samples were determined and were between 14 and 67 μm. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010