Nd(naph)3-Al(i-Bu)3催化邻苯二甲酸酐与环氧丙烷交替共聚

Ｎｄ（ｎａｐｈ）３Ａｌ（ｉＢｕ）３催化邻苯二甲酸酐与环氧丙烷交替共聚房江华黄士力（宁波师范学院化学系，宁波３１５０２０）沈之荃（浙江大学高分子科学与工程学系，杭州３１００２７）关键词环烷酸钕，交替共聚，邻苯二甲酸酐，环氧丙烷分类号Ｏ６４３／ＴＱ３...     

Nd(naph)3-Al(i-Bu)3催化马来酸酐和环氧丙烷交替聚合

研究了马来酸酐和环氧丙烷的交替共聚，发现Ｎｄ（ｎａｐｈ）３－Ａｌ（ｉ－Ｂｕ）３是马来酸酐（ＭＡｎ）和环氧丙烷（ＰＯ）交替共聚的良好催化剂，用红外光谱，核磁共振研究了共聚物的结构。共聚反应动力学研究表明共聚反应与单体和催化剂浓度均呈一级关系。表观活化能为１１ｋｊ／ｍｏｌ.     

稀土催化体系Nd(napb)_3-AlEt_2Cl-Al(i-Bu)_3对双烯烃聚合的活性

分析了催化剂Nd(naph)_3-AlEt_2Cl-Al(i-Bu)_3三组分反应产物的组成,用动力学方法研究了其催化异戊二烯聚合的活性。催化剂各组分的配比及制备方法对其活性及利用率有显著影响。催化剂的利用率随它使用时浓度的减小而增大,最后达到恒定链终止反应由体系中过量的AlEt_2Cl吸附于活性体而发生。     

Nd(O-i-Pr)3-Al(i-Bu)3配位催化甲基丙烯酸甲酯聚合反应的研究

甲基丙烯酸甲酯(MMA)能以自由基引发聚合,也能以格氏试剂、烷基锂或烷基铝引发阴离子聚合[1].六十年代来,ABE等人研究了Ti、V、Cr、Co、Mn等的Ziegler-Natta催化剂的催化聚合反应,提高聚合物的规整性[2].近年来出现了稀土配位催化聚合MMA及其它丙烯酸酯的报道[2～7],但较少有Nd(O-i-Pr)3配位催化MMA聚合的报道.     

Fe(acac)3-Al(i-Bu)3-8-羟基喹啉催化体系催化丙烯酸甲酯聚合

研究了Fe(acac)3-Al(i-Bu)3-8-羟基喹啉（acac=乙酰丙酮）催化体系催化丙烯酸甲酯（MA）聚合，用凝胶渗透色谱研究了聚合物分子量和分子量分布，结果显示，分子量分布很窄，动力学研究表明，聚合反应对单体浓度呈一级关系，表观活化能为39．1KJ／mol。     

Nd(O-i-Pr)_3-Al(i-Bu)_3配位催化甲基丙烯酸甲酯聚合反应的研究

Ｎｄ（Ｏ ｉ Ｐｒ）３ Ａｌ（ｉ Ｂｕ）３配位催化甲基丙烯酸甲酯聚合反应的研究孙俊全（浙江大学高分子科学与工程系杭州３１００２７）（中国科学院长春应化所稀土化学与物理开放实验室长春１３００２２）关键词聚合反应，配位聚合，稀土催化剂，甲基丙烯酸甲酯，...     

杯[8]芳烃钕-Al(i-Bu)3体系催化乙烯聚合

杯芳烃是由对叔丁基苯酚经亚甲基2,4-位桥联的一类大环多羟基化合物,被誉为继冠醚和环糊精之后第三代有特色的主体分子,引起了许多化学学者的研究兴趣.杯芳烃在相转移催化、物质分离、制作分子器件等方面有着广泛的应用前景[1].     

稀土催化合成等规聚苯乙烯

稀土催化合成等规聚苯乙烯刘丽郑玉莲龚志＊景遐斌（中国科学院长春应用化学研究所长春１３００２２）关键词等规聚苯乙烯，稀土配位催化剂，苯乙烯，配位聚合１９９７－０１－０４收稿，１９９７－０６－０３修回催化合成等规聚苯乙烯的催化剂主要有钛、镍等体系［１，２...     

Studies on Ring—Opening Polymerization of Chloromethyl Thiirane with Rare Earth Catalysts and Functional Resins Synthesized therewith

Studies on ring-opening polymerization of chloromethyl thiirane with rare earth catalysts and functional resins synthesized therewith were reviewed.     

一种对异戊二烯立体控制聚合较敏感的稀土催化体系

发现了一种对异戊二烯聚合立体选择性较敏感的稀士催化体系：（β－ＣＨ＿３－ａｌｌｙｌ）＿２ＬｎＣｌ＿５Ｍｇ·２Ｔ的ＥＤ（Ｌｎ）－Ｒ＿３Ａｌ（Ａｌ）（Ｌｎ＝Ｎｄ、Ｃｅ和Ｌａ，Ｔ的ＥＤ：Ｎ，Ｎ，Ｎ′，Ｎ′－四甲基乙二胺；Ｒ＝Ｍｅ一，Ｅｔ一，ｉ－Ｂｕ一和Ｏｃｔ一）．该催化体系在改变聚合温度、聚合时间、Ａｌ／Ｌｎ摩尔比、溶剂等时，可使聚异戊二烯的立体现整度有较大的改变，其中顺式－１，４、反式－１，４和３，４－链节含量的变化范围分别为１９％～７９％、１７％～７８％和０％～３．５％，还可获得较低分子量的聚合物。     

稀土与甘氨酰－L－亮氨酸的配位作用

用ｐＨ电位法测定了生理条件下（３７℃，Ｉ＝０．１５ｍｏｌ／Ｌ）和２５℃，Ｉ＝０．１０ｍｏｌ／Ｌ时甘氨酰－Ｌ－亮氨酸的质子化常数及其稀土配合物稳定常数，结果表明稀土可与该配体形成１：１配合物，并且配合物稳定性呈现明显“四分组效应”。讨论了钇的位置以及肽键对配合物稳定性的影响。     

稀土与甘氨酰—L—亮氨酸的配位作用

用ｐＨ电位法测定了生理条件（３７℃，Ｉ＝０．１５ｍｏｌ／Ｌ）和２５℃，Ｉ＝０．１０ｍｏｌ／Ｌ时甘氨酰Ｌ－亮氨酸的质子化常数及其稀土配合物稳定常数。结果表明稀土可与该配体形成１：１配合物，并且配合物稳定性呈现明显“四分组效应”。讨论了钇的位置以及肽键对配合物稳定性的影响。     

Solution-reaction Calorimetric Study of Coordination Compounds of Rare Earth Perchlorates with Alanine and Imidazole

Introduction Since Anghileri firstly reported that complex of LaCl3 with glycine had the antitumor function in 1975,1 coordination compounds of rare earth with amino acid have attracted increasing attention.2-4 People have found that some compounds of rare earth with amino acids possess disinfection, elimination of inflammation, de-crease of the level of blood sugar and anti-cruor func-tions. Imidazole is a wreath compound, and presents unique biological activities. Ternary coordination com-…     

Syndiospecific Polymerization Catalysts for Styrene Based on Rare Earth Metal Half-Sandwich Complexes

In the presence of an trialkyl aluminum cocatalyst the activation of scandium, yttrium and lutetium mono(cyclopentadienyl) complexes with various substituted cyclopentadienyl ligands by [Ph₃C][B(C₆F₅)₄] results in highly efficient catalysts for the syndiospecific polymerization of styrene. As active species half-sandwich alkyl cations is assumed that is isostructural with the mono(cyclopentadienyl) titanium alkyl cation originally proposed by Zambelli.     

Rare Earth Polymer Complex Catalyst for Ring Opening Polymerization of Epichlorohydrin

ＲａｒｅＥａｒｔｈＰｏｌｙｍｅｒＣｏｍｐｌｅｘＣａｔａｌｙｓｔｆｏｒＲｉｎｇＯｐｅｎｉｎｇＰｏｌｙｍｅｒｉｚａｔｉｏｎｏｆＥｐｉｃｈｌｏｒｏｈｙｄｒｉｎＳＨＥＮＺｈｉ－ｑｕａｎ，ＪＩＡＮＧＤｏｎｇ－ｌｉｎａｎｄＺＨＡＮＧＹｉ－ｆｅｎｇ（Ｄｅｐａｒｔｍ...     

Mixed Aluminum‐Magnesium‐Rare Earth Allyl Catalysts for Controlled Isoprene Polymerization: Modulation of Stereocontrol

Summary: The performances of readily available Ln(allyl)₂Cl(MgCl₂)₂ · (THF)₄ precursors (Ln = Nd, 1 ; Y, 2 ; La, 3 ), in combination with alkyl aluminum activators [MAO, AlMe₃, AlEt₃, Al(iBu)₃], have been studied in isoprene polymerization. The catalyst combination 1 /MAO (1:30) shows a high activity (average TOFs up to ca. 5 × 10⁴ mol (Ip) · mol (Nd)⁻¹ · h⁻¹ at 20 °C) and produces polyisoprene in a controlled fashion with up to 98.5% cis content, number‐average molecular weights in reasonable agreement with calculated values, and relatively narrow polydispersities index ( = 1.20–1.70). The yttrium precursor 2 affords systems with much lower activity and degree of control, but enables the formation of either 1,4‐cis‐enriched (75%) or 1,4‐trans‐enriched (91%) polyisoprenes, simply replacing the MAO activator by AlEt₃ or Al(iBu)₃, respectively.

Formation of 1,4‐cis‐ or 1,4‐trans‐enriched polyisoprenes upon activation with MAO.     

Polymerization of 4—Vinylpyridine by Lanthanide Coordination Catalyst

Polyvinylpyridines are an important class of polymers that exhibit interesting properties due to the presence of the nitrogen atom in the pyridine ring. The weakly basic nitrogen atom makes possible a variety of reactions on vinylpyridine polymers, e.g. reaction with acids, quaternization and complexation of metals. In addition, these polymers are mainly attractive in applications as polyelectrolytes, polymeric reagents etc. Few papers about polymerization of 4-vinylpyridine (4-Vpy) with co…