负载型茂金属催化剂的研究进展

茂金属负载化是拓宽其使用范围、降低其使用成本、改善聚合产物形态的有效手段。文章介绍了茂金属在SiO2、沸石、聚苯乙烯等载体上的负载方法、负载机理，综述了负载型茂金属催化剂在催化烯类单体聚合方面的应用，指出了今后的改进方向。     

烯烃配位活性聚合催化剂的研究进展

综述了茂/单茂金属催化剂、二元胺前过渡金属催化剂、α-二亚胺后过渡金属催化剂和水杨醛亚胺前过渡金属催化剂在烯烃配位活性聚合中的研究进展,以及各种催化剂催化烯烃配位活性聚合的实例和影响配位活性聚合的关键因素。这四种烯烃配位活性聚合催化剂中,茂/单茂金属催化剂的研究结果最成熟,但其他三种非茂体系的催化剂具有制备容易、催化烯烃配位活性聚合的条件温和、在实际应用中易实现的优势。此外,采用多重活性聚合的方法能解决配位活性聚合时催化剂利用率低的问题。     

茂金属催化剂催化丙烯聚合研究进展

介绍了茂金属催化剂催化丙烯聚合的发展概况、催化剂结构与聚合物微观结构的关系、丙烯聚合机理及催化体系的结构组成对丙烯聚合的影响     

茂金属催化剂的发展及应用

详细阐述了各种不同茂金属催化剂的结构、功能和特点，深入地探讨了茂金属催化剂的催化聚合作用机理及其在聚烯烃工业中的应用，论述了茂金属催化剂对聚合物加工性能、力学和物理性能以及共聚单体的影响，文中结尾综述了国外茂金属催化剂在聚烯烃合成中的应用现状。     

茂锆金属催化剂催化乙烯聚合研究

主要考察了含锆的茂金属催化剂中催化乙烯反应条件优化研究,在最优条件下催化聚合反应所得的产物与吉林石化公司聚乙烯厂聚乙烯产品进行分析对比.对茂锆金属催化剂催化乙烯聚合反应条件研究表明,适宜的助催化剂[Al]与主催化剂[Cat]的摩尔比在1 500左右,适宜的主催化剂浓度在1.5×10-4 mol/L左右,最佳聚合温度60℃,此时催化剂的活性可达到106 gPE/(molCat·h).从物理性能、热性能、相对支化度、相对分子质量及其分布分析可知,制备出的负载茂锆金属催化剂在最优反应条件下催化乙烯聚合所得的产物与吉林石化公司聚乙烯产品性质基本一致,符合产品的指标,支链分布均匀,分子量分布更窄.同时对茂锆金属催化剂主、助催化剂催化乙烯聚合的作用和机理进行了探讨.     

离子型茂金属催化丙烯聚合的研究进展

综述了以硼化合物为助催化剂的离子茂金属催化剂催化丙烯聚合的研究进展,介绍了用不同催化体系制备的不同结构的聚丙烯的性能及用途,并对聚合机理进行了探讨 。     

茂金属／硼化物催化体系用于烯烃聚合的研究进展

发茂金属／硼化物催化体系的研究进展。包括硼化物的合成、聚合机理及催化剂的结构对聚合体系的影响。     

茂金属聚丙烯催化剂概述

聚丙烯是一种生活中应用非常广泛的材料,其中丙烯聚合催化剂的进步是聚烯烃工业蓬勃发展的关键。具有独特性能和优势的茂金属聚丙烯催化剂在过去的几十年中引起了人们极大的研究兴趣。综述了茂金属聚丙烯催化剂的结构、组成,助催化剂以及茂金属催化丙烯聚合机理。重点介绍了非桥联茂金属催化剂以及桥联茂金属催化剂,其中桥联茂金属化合物因桥基的刚性骨架结构,使得其与聚丙烯规整度紧密相连。还详细介绍了C_2、C_(2v)、C_s、C_1不同对称性对聚丙烯规整度的影响。     

低共聚单体引入型茂金属催化剂化合物

本发明提供聚合催化剂化合物催化剂体系和它们在乙烯和至少一种共聚单体的聚合中的用途。尤其，本发明涉及鉴别茂金属聚合催化剂化合物的共聚单体引入行为。更具体地说，本发明涉及鉴别微量引入共聚单体的茂金属催化剂化合物。优选此类茂金属催化剂化合物含有至少一种取代的或未被取代的稠环环戊二烯基型配位体。本发明还涉及这些低的共聚单体引入型茂金属催化剂化合物在生产聚合物的催化剂体系中的应用，     

茂金属催化剂及其聚烯烃的开发

报导了中国石油化工总公司石油化工科学研究院近两年茂金属催化剂及其催化烯烃聚合技术的研究进展，间规选择性复合型茂金属论剂技术已开发成功；用基催化珙烯聚合，在国内首次得到合格的商业用间规聚丙烯；完成了限制几何构型复合型茂金属的合成探索，获得具有较好活性的系列催化剂。实现了茂金属催化剂的负载化为茂金属催化剂在相烯烃聚合工艺中的应用奠定了基础。     

乙烯与极性单体共聚的研究进展

聚烯烃属于非极性聚合物,通过在其分子链上引入极性基团可以将其功能化,从而可以有效地改善聚烯烃的性质,拓宽聚烯烃的商业用途。本文主要从极性单体的种类、乙烯与极性单体共聚的催化剂体系两个方面介绍了乙烯与极性单体共聚合研究的最新进展。Ziegler-Natta催化剂、茂金属催化剂以及后过渡金属催化剂都可用于乙烯与极性单体的共聚合反应。文中重点介绍了后过渡金属催化剂,其催化活性高,聚合能力强,可以催化乙烯与大多数极性单体的共聚反应。     

Polymerization of olefins and polar monomers catalyzed by bis(imino)Ni(II)/dibutylmagnesium/alkylaluminium halide systems

[Bis(N,N′‐dimesitylimino)acenaphthene]dibromonickel ( 1 ) when activated with diethylaluminium chloride (DEAC) is a very active catalyst for ethylene homopolymerization. The activity (A_E) of 1 /100 DEAC is twenty times greater than that of 1 /100 MAO and of the same order of magnitude as 1 /2000 MAO. In the case of homopolymerization of propylene the highest activity (A_P) was obtained at a ratio of 25/15 for Al_DEAC/Ni. Trialkylaluminium compounds were also found to act as cocatalysts for 1 . The PE synthesized with four different cocatalysts was found by ¹³C NMR to have dissimilar branching distributions. 1 /DEAC shows no activity for the polymerization of proximately substituted polar monomers. The introduction of dibutylmagnesium, (DBM) activates the 1 /DEAC system to copolymerize ethylene and a number of proximately substituted polar monomers. Compared with the 1 /MAO/monomer.AlR₃ catalyst system the former is three times more active for copolymerization of 5‐hexene‐1‐ol or 10‐undecen‐1‐oic acid with ethylene. The activity of copolymerization is 1 /24, 1 /5 and 1 /2 as active as homopolymerization, respectively, in the case of methyl vinyl ketone, vinyl acetate and ?‐caprolactam. In the case of tetrahydrofuran/ethylene, the 1 /MAO catalyst produced copolymers using AlR₃ pretreated THF whereas the 1 /DEAC/DBM catalyst produces homopolyethylene only. No polymerization occurred with an acrylonitrile/ethylene mixture in the presence of 1 /DBM/DEAC catalyst. © 2002 Society of Chemical Industry     

Polymerization of olefins through heterogeneous catalysis. XVIII. A kinetic explanation for unusual effects

The development of a detailed kinetic model describing some of the unusual effects observed in catalyzed olefin polymerization is presented. Based on the method of moments, the model describes the rate effects of hydrogen and comonomers, as well as the ability of certain systems to incorporate long chain branches via internal and/or terminal double bond polymerization. Examples are provided demonstrating the model's ability to predict rates and degrees of polymerization with ethylene, propylene, and 1-hexene monomers. In the case of propylene, multiple insertion mechanisms are modeled and compared with experimental sequence length and end group data. In other examples the model is used to simulate an oscillating metallocene catalyst and a metallocene catalyst capable of branch addition via terminal double bond polymerization. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:1053–1080, 1997     

新型后过渡金属烯烃催化剂的研究进展

综述了近年来－系列新型α－二亚胺型后过渡金属（Ni、Pd、Fe、Co）催化剂在烯烃聚合、极性单体共聚、烯烃齐聚、环烯烃加成聚合、烯烃活性聚合和聚烯烃纳米复合物等方面的最新进展。系统地阐述了不同的中心过渡金属离子、α－二亚胺骨架、骨架上的取代基和不同的聚合条件（温度、压力）分别对催化剂的聚合活性、聚烯烃支化率、聚合物分子量和分子量分布以及聚合产物的性质等影响，并且简要说明了这一类催化剂的制备方法和新特点。     

Catalytic activity during the preparation of PE/clay nanocomposites by in situ polymerization with metallocene catalysts

Catalytic activity during the formation of polyethylene (PE)/clay nanocomposites by in situ polymerization with metallocenes was studied. Ethylene polymerization was carried out with the homogeneous metallocene in the presence of the clay particles and using the clay‐supported metallocene catalyst. It was found that the catalytic activity of the homogeneous metallocene does not decrease in the presence of the clay particles and only a slight decrease of activity occurs using the clay‐supported catalyst. The modification of the clay with MAO cocatalyst as well as its intercalation with ODA surfactant were found to play an important role during the in situ formation of the PE/clay nanocomposite. ODA‐intercalated clay apparently facilitates the activation and monomer insertion processes on zirconocene centers located in internal sites of the clay structure. Although metallocene supported on MAO‐treated clay exhibited somewhat lower catalytic activity than that supported directly on the ODA‐intercalated clay, both systems favored the production of PE nanocomposites containing highly exfoliated clay particles. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Experimental proof of the existence of mass‐transfer resistance during early stages of ethylene polymerization with silica supported metallocene/MAO catalysts

The size of a silica supported metallocene/MAO (methylaluminoxane) catalyst plays an important role in determining its productivity during ethylene polymerization. From a chemical engineering point of view, this size dependency of catalytic activity of supported metallocenes is mathematically connected with the different levels of mass‐transfer resistance in big and small catalyst particles but no experimental evidence has been provided to date. The results of this systematic experimental study clearly demonstrate that the intraparticle monomer diffusion resistance is high in bigger catalyst particles during initial instants of ethylene polymerization and diminishes with the polymer particle growth. Two different silica supported metallocene/MAO catalysts provided the same results while highlighting the fact that catalyst chemistry should be carefully considered while studying complex chemical engineering problems. © 2017 American Institute of Chemical Engineers AIChE J, 63: 4476–4490, 2017     

茂金属催化剂的研究进展

介绍了茂金属催化剂合成技术,重点阐述了非桥联型、桥联型、限定几何构型、离子型和负载型茂金属催化剂的合成、结构及性能。     

三齿配体过渡金属烯烃聚合催化剂研究新进展

介绍了三齿配体结构、中心金属原子、助催化剂、负载化等对催化剂性能的影响;综述了三齿配体过渡金属烯烃聚合催化剂在乙烯齐聚、乙烯聚合、丙烯聚合以及极性单体聚合方面的应用以及三齿配体过渡金属烯烃聚合催化剂的催化机理方面的研究进展。     

Effects of the solvent polarity on the atom transfer radical polymerization of methyl methacrylate initiated by 4‐(chloromethyl)phenyltrimethoxysilane

The controllability of the atom transfer radical polymerization of methyl methacrylate in the polar solvent N,N‐dimethylformamide and the nonpolar solvent xylene with 4‐(chloromethyl)phenyltrimethoxysilane as an initiator and with CuCl/2,2′‐bipyridine and CuCl/4,4′‐di(5‐nonyl)‐2,2′‐bipyridine as catalyst systems was studied. Gel permeation chromatography analysis established that in the nonpolar solvent xylene, much better control of the molecular weight and polydispersity of poly(methyl methacrylate) was achieved with the CuCl/4,4′‐di(5‐nonyl)‐2,2′‐bipyridine catalyst system than with the CuCl/2,2′‐bipyridine as catalyst system. In the polar solvent N,N‐dimethylformamide, unlike in xylene, the polymerization was more controllable with the CuCl/2,2′‐bipyridine catalyst system than with the CuCl/4,4′‐di(5‐nonyl)‐2,2′‐bipyridine catalyst system. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2751–2754, 2007