C1桥联的茂金属化合物（Cp）CR1R2（Flu）MCl2的合成及其 …

合成了６种单碳桥联的含芴（Ｆｌｕ）茂（Ｃｐ）基ⅣＢ族茂金属催化剂,研究了它们催化烯烃聚合的能力。通过ＩＲ,＾１Ｈ ＮＭＲ,ＥＩ－ＭＳ和元素分析对化合物进行了表征。用所合成的茂金属化合物与ＭＡＯ所组成的催化体系对乙烯、丙烯的聚合进行了研究。其中金属为Ｔｉ的催化剂没有聚合活性或活性极低。金属为Ｚｒ的催化剂有一定的催化活性,用不同的催化剂得到的聚合物性质有一定的差异。     

茂金属催化剂Cp_2~tMCl_2(Cp~t=~tBuC_5H_4,M=Ti、Zr、Hf)聚合丁烯-1的研究

探讨了茂金属催化剂 Cpt2 MCl2 ( Cpt=t Bu C5 H4,M=Ti,Zr,Hf)的合成以及用于聚合丁烯 -1的研究 ,研究了几种不同的茂金属催化剂和不同聚合条件下的催化行为 ,并通过 IR、1 H NMR、EI-MS、DSC、粘度法测分子量和正庚烷抽提等测试手段对催化剂和聚合物进行了表征 .结果表明 ,叔丁基取代的茂金属催化剂催化丁烯 -1聚合具有较高的催化活性 ,叔丁基的引入提高了聚合物的等规度和分子量     

茂钛催化剂聚1-丁烯的合成

茂金属催化烯烃聚合以其高活性、定向性等特点受到广泛重视.Ｋａｍｉｎｓｋｙ[1～4]等用二茂基(Ｃｐ、Ｉｎｄ和Ｆｌｕ)过渡金属(Ｔｉ、Ｚｒ和Ｈｆ)化合物/ＭＡＯ催化剂催化1丁烯聚合,可得到间规(ｓＰＢ)、无规(ａＰＢ)或等规(ｉＰＢ)聚1丁烯.Ｌｉｎ[5]和Ｗｕ[6]分别用单茂基的ＣｐＴｉ(ＯＰｒ)3/ＭＡＯ和ＣｐＴｉ(ＯＢｚ)3/ＭＡＯ催化剂进行丙烯聚合,都得到无规聚丙烯(ａＰＰ),并研究了催化体系中Ｔｉ氧化态分布,认为Ｔｉ+4有利于α烯烃聚合.有关用单茂钛化合物/ＭＡＯ催化体系催化1丁烯聚合的研究目前较少文献报道.本文用新型茂钛催化剂—…     

CpTiCl2(OR)/MAO体系催化苯乙烯间规聚合的研究

茂金属催化剂广泛应用于催化α-烯烃和苯乙烯的定向聚合. 与传统的Ziegler-Natta催化剂相比, 茂金属催化剂催化活性中心单一, 聚合过程立体定向性强, 且往往得到用常规方法所不能得到的新型聚合物［1～5］. Ishihara等［6］首次采用钛金属有机化合物与甲基铝氧烷(MAO)体系催化苯乙烯聚合, 分离得到间规聚苯乙烯, 从此揭开了苯乙烯定向聚合的新篇章, 合成了大量茂金属有机化合物, 用于催化苯乙烯间规聚合, 其中半夹心结构的茂金属化合物CpTiX3［7,8］, IndTiCl3［3,4,9,10］［Cp=(未)取代环戊二烯基, Ind=(未)取代茚基; X=Cl, F, 烷氧基等］具有最好的催化活性及间规定向性. (CpHMe4)TiF3［8］催化活性高达1.01×108 g PS/(mol Ti*h), 间规度≥95%.     

茂金属催化剂Cpt2MCl2(Cpt=tBuC5H4，M=Ti、zr、Hf)聚合丁烯-1的研究

探讨了茂金属催化剂Cpt2MCl2(CPt=tBuC5H4,M=Ti,zr,Hf)的合成以及用于聚合丁烯-1的研究,研究了几种不同的茂金属催化剂和不同聚合条件下的催化行为,并通过IR、1H NMR、EI-MS、DSC、粘度法测分子量和正庚烷抽提等测试手段对催化剂和聚合物进行了表征．结果表明,叔丁基取代的茂金属催化剂催化丁烯-1聚合具有较高的催化活性,叔丁基的引入提高了聚合物的等规度和分子量．     

MgCl_2负载(dbm)_2Ti(OPh)_2催化乙烯聚合

烯烃聚合的新型非茂催化剂由于合成相对简便并具有一些新特点,近年来开始受到人们的关注[1,2].ＩＶＢ族金属的β二酮络合物与烷基铝或烷氧基铝形成的催化体系对烯烃聚合也显现出一定的聚合活性.在一定压力下,β二酮锆/ＭＡＯ均相催化乙烯聚合时具有较高聚合活性[3].β二酮钛催化剂对于丙烯无规聚合和苯乙烯间规聚合均有较好结果[4～6].本文将报道用ＭｇＣｌ2负载的二苯氧基二(二苯甲酰甲烷)钛络合物((ｄｂｍ)2Ｔｉ(ＯＰｈ)2),以甲基铝氧烷(ＭＡＯ)为助催化剂,常压催化乙烯聚合的结果.1　原料ＭｇＣｌ2为抚顺301厂产品.ＭＡＯ(1.4ｍｏｌ/Ｌ甲…     

Ind2Zr(OC6H4Me-P)2和EtnAICL3-n催化乙烯齐聚的研究

茂金属催化剂 ( Kaminsky催化剂 )是 80年代发展起来的烯烃聚合高效催化剂 [1] ,有关其催化烯烃聚合的研究很多 [2～ 4 ] .近年来 ,Kaminsky型催化剂催化乙烯齐聚合成低碳α烯烃的研究已有报道 [5] .由乙烯齐聚得到的直链低碳α烯烃是生产线性低密度聚乙烯 ( LL DPE)和高密度聚乙烯 ( HDPE)的共聚单体 .以茚基锆化合物与烷基铝组成的 Ziegler- Natta催化体系催化乙烯齐聚尚未见报道 .本文考察了Ind2 Zr( OC6H4 Me- p) 2 和各种乙基铝组成的二元催化体系对乙烯齐聚的催化性能 .1　实验部分　　二茚基锆配合物 Ind2 Zr Cl2 和 Ind2 …     

含8-羟基喹啉类配体的新型钛配合物[O,N]CpTiCl_2的合成及其催化乙烯聚合研究

茂金属催化烯烃聚合的活性中心被认为是1 4电子结构的金属阳离子配合物 [Ｃｐ2 ＭＲ]+ (Ｒ为烷基 ) ,并且金属中心的Ｌｅｗｉｓ酸性和周围茂配体的空间构型对其催化活性及聚合产物的结构有直接的影响[1,2 ] .然而 ,茂金属须大量ＭＡＯ存在下才能显示高活性 ,并且其稳定性较差 ,这都一定程度上限制了茂金属催化剂的实际应用 .近几年来 ,将含非环戊二烯基配体的金属配合物应用于烯烃均相聚合的研究大量出现[3] ,其中非环戊二烯基配体有含氮化合物[4～ 9] 和含氧化合物[10～ 15] 等 ,这些非茂配合物可催化乙烯或丙烯聚合 ,但活性一般较低 .茂金…     

双组分茂金属催化剂催化乙烯聚合的研究

选择能形成支链的不对称桥联茂金属化合物Me2 C[(Cp) (Ind) ]ZrCl2 和非桥联的不同结构的茂金属化合物二氯二 (烯基取代环戊二烯 )锆如 ( Cp) 2 ZrCl2 ,(Cp) 2 ZrCl2 和 (Cp) 2 ZrCl2 ,以MAO为助催化剂 ,分别组成三组双组分茂金属催化剂的催化体系 ,催化乙烯聚合 .结果表明 ,两类催化剂组成的双组分茂金属催化体系催化乙烯聚合能得到支化的宽分子量分布的聚乙烯 ;聚合温度和改变两种茂金属催化剂的摩尔比对催化活性和分子量有很大影响 .因此可以利用改变双组分茂金属催化剂的摩尔比例和聚合温度来调控聚合物的分子量和分子量分布 .改变两种茂金属催化剂的摩尔比和聚合温度也能使聚合物的结晶度发生改变     

茂金属聚合催化剂的研究现状

198 0年德国汉堡大学的化学家 Sinn等[1] 发现了烯烃聚合用的茂金属催化剂 .茂金属催化剂为两个环戊二烯中间夹有过渡金属如 Zr、Hf、Ti等的具有三明治结构的有机金属化合物 .茂金属催化剂与传统的多相 Ziegler- Natta催化剂相比 ,具有可溶且聚合活性物种单一 ,对乙烯等烯烃的聚合活性高 ,高分子产物的分子量及组成分布窄等特点 .选择不同的茂金属催化剂 ,可获得所需立构规整性的高分子物 ,除能获得全同立构的聚烯烃外 ,还可获得由 Ziegler- Natta催化剂不能合成的间规立构聚烯烃 ,如聚苯乙烯 [2 ]与聚丙烯 [3 ] .由 Ziegler- Natta催化…     

Self-immobilizing catalysts and cocatalysts for olefin polymerization

Homogeneous catalysts for olefin polymerization such as metallocene or half-sandwich complexes containing the metals titanium, zirconium and hafnium, or other transition-metal coordination complexes can be functionalized with alkenyl groups and have then the potential to copolymerize with olefins to give heterogeneous catalysts. In a similar manner metallacyclic metallocene complexes with a metal-carbon sigma bond allow the catalytic insertion of olefins into this bond and produce heterogeneous catalysts. It is also possible to functionalize the active species of the cocatalyst methylalumoxane (MAO) and use it for self-immobilization processes. The high excess of MAO that is necessary in homogeneous solution can be reduced by more than 90% with this method.     

A New Zirconocene Complex and Its Catalytic Properties for Olefin Polymerization

As metallocene olefin polymerization catalysts,unbridged metallocenecomplexeshave re-ceived much attention because they are relatively easy to be synthesized and can produce notonly polyethylene butalso oligo-or polypropylenes with differentstereoregularities and prop-erties depending on their structures[1 ,2 ] .It has been known that a rather small structuralchange for a metallocene compound may cause a remarkable effect on its catalytic properties,such as catalytic activity,polymer molecule w…     

双核茂金属催化剂催化聚合反应进展

综述了双核茂金属化合物的研究进展及其在烯烃和极性单体聚合方面的应用及双核茂金属化合物的合成及性能研究；并对双核催化剂的作用机理、催化剂结构与性能的关系也做了介绍。     

Novel polystyrene‐supported zirconocene catalyst for olefin polymerization and its catalytic kinetics

Through the Diels–Alder reaction between cyclopentadiene groups attached to polystyrene in the presence of zirconocene, novel polystyrene‐supported metallocene catalysts were prepared. A novel method for immobilizing metallocene catalysts was investigated, and the resultant polystyrene‐supported metallocene for olefin polymerization was studied. The results of olefin polymerization showed that different crosslinking degrees of support in the catalyst system had significant effects on the catalytic behavior. The influence of the [Al]/[Zr] molar ratio and the temperature on the (co)polymerization activity was studied. When 1‐hexene and 1‐dodecene were used for copolymerization with ethylene, an obvious positive comonomer effect was observed. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2650–2656, 2005     

Fluorinated bis(phenoxy-imine) Ti complexes with MAO: Remarkable catalysts for living ethylene and syndioselective living propylene polymerization

Based on new results as well as the reported data, the ethylene and propylene polymerization behavior of bis(phenoxy-imine) Ti complexes (Ti-FI Catalysts) combined with MAO (particularly that of their fluorinated versions) is discussed, with an emphasis on the characteristics and mechanisms of living ethylene and syndioselective living propylene polymerization. Unlike common living olefin polymerization catalysts, fluorinated Ti-FI Catalysts with MAO display thermally robust living behavior and polymerize ethylene in a highly controlled manner at temperatures as high as 50 °C. Additionally, despite being C₂-symmetric catalysts, fluorinated Ti-FI Catalysts/MAO mediate highly syndioselective living propylene polymerization. Fluorinated Ti-FI Catalysts that we developed are the first examples of catalysts that induce the living polymerization of both ethylene and propylene. In addition, they are also the first examples of living and, at the same time, highly stereoselective propylene polymerization catalysts. The versatile and robust living nature of the fluorinated Ti-FI Catalysts allows the preparation of a wide variety of unique living polymers; some of which can even be produced catalytically. On the basis of theoretical calculations as well as experimental results, we conclude that these unusual polymerization features of fluorinated Ti-FI Catalysts originate from an attractive interaction between the ligand and a growing polymer chain and/or the fluxional character of the catalyst coupled with 2,1-regiochemistry. This is in stark contrast to group 4 metallocene catalysts, which control olefin polymerization mainly by repulsive interactions based on the rigidly organized ligand frameworks.     

IVB金属配合物催化烯烃聚合的研究进展

IVB金属配合物催化烯烃聚合的研究,不仅为工业界提供大量新型高效的催化剂模型,同时也为探索烯烃配位聚合机理提供了可能.更为重要的是,这些新型的配合物催化剂,可以制备具有优异性能的新型聚烯烃树脂.研究的核心仍然是新型聚烯烃催化剂,基于配合物中配位原子种类的不同,将催化剂的种类分为氮配位和氧配位催化剂.文中综述了近年来IVB金属配合物作为烯烃聚合催化剂的研究进展,集中讨论催化剂结构的变化对催化性能的影响.     

茂金属催化剂的负载化

负载化是茂金属催化剂发展的一个新方向。本文系统地描述了茂金属负载化催化剂的主要制备方法;分析了活性中心的本质、结构以及生成机理;并且讨论了负载化对茂金属催化剂烯烃聚合性能的影响。     

The discovery of metallocene catalysts and their present state of the art

Metallocene and other transition metal complexes activated by methylaluminoxane are highly active catalysts for the polymerization of olefins, diolefins, and styrene, which was discovered at the University of Hamburg about 25 years ago. These catalysts allow the synthesis of polymers with a highly defined microstructure, tacticity, and stereoregularity, as well as new copolymers with superior properties such as film clarity, tensile strength, and lower extractables. A better understanding of the mechanism of olefin polymerization leads to findings of other new single site catalysts. The development of the metallocene/MAO‐catalysts from their discovery to their present state of the art is presented. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3911–3921, 2004     

负载型烯烃聚合催化剂合成的新方法

介绍了负载型烯烃聚合催化剂合成的新方法,探讨了不同载体负载的Ziegler- Natta催化剂各组分之间的相互作用机理及活性中心的形成途径。对负载茂金属催 化剂的新型载体及新的负载方法进行了评述。     

烯烃聚合催化剂的研究进展

获得高性能聚烯烃材料是化学家们不断的追求。烯烃聚合催化剂的结构对其催化性能有重要影响,而聚烯烃的改性则能够改善聚合物实际应用中表面形貌、本体性能中存在的缺陷,如通过改性可增加聚合物韧性、降低聚合物表面的摩擦系数或提升表面能等。 本文系统总结了金属烯烃聚合催化剂研究进展,包括Ziegler-Natta催化剂、茂金属催化剂、非茂金属催化剂的结构及调控策略,探讨了位阻效应、双金属协同效应以及其他效应对催化效果的影响。