【摘 要】
：
Some highly active η5-pentamethylcyclopentadienyltribenzyloxy titanium complexes [Cp*Ti(Obz)3] activated by modified methylaluminoxane (mMAO) were prepared and
【机 构】
：
Institute of Polymer Science
论文部分内容阅读
Some highly active η5-pentamethylcyclopentadienyltribenzyloxy titanium complexes [Cp*Ti(Obz)3] activated by modified methylaluminoxane (mMAO) were prepared and used as the catalyst for styrene syndiospecific polymerization and propene atactic polymerization. Styrene could be copolymerized with propene when the propene was prepolymerized for a period, to which styrene and tri-isobutylaluminum (TIBA) were then added. The titled block copolymer together with the related homopolymers was obtained. The copolymerization porducts can be divided into the homopolymers and the copolymer by successive solvent extraction with boiling butanone, heptane and tetrahydrofuran (THF), and each fraction was characterized by 13C NMR, DSC and WAXD. It was found that aPS and aPP were soluble in boiling butanone and heptane respectively. The block copolymer (sPS-b-aPP) composed of syndiotactic polystyrene segment was soluble in boiling THF and the residue was chiefly sPS.
其他文献
Reaction of Mo(CO)6 with p-H3CO-C6H4SNa and Et4NCl · H2O in CH3CN afforded a dinuclear molybdenum(0) compound [Et4N]2[Mo2 (CO)8 (SC6H4-OCH3-p)2] (1). The cryst
The Trefftz-type boundary solution methods[1] are applied in analysing moderately thick plate bending problems. A new type of locking problem caused by the over
In this paper,it is shown that Quasi-Wilson element possesses a very special property i.e.the consistency error is of order O(h2),one order higher than that of
Two new diterpenoids taibairubescensin A (1) and B (2) have been isolated from Isodon rubescens.The structures of compound 1 and 2 were elucidated as 2b ,3b -di
The authors obtain a new property of the n-dimensional binary undirected de Bruijn graph UB(n) for n≥4, namely, there is a vertex x such that for any other ver
对Ｉｎｃｏｎｅｌ７１８合金及其表面分别注入３×１０１６Ｙ＋／ｃｍ２和３×１０１７Ｙ＋／ｃｍ２剂量钇的样品在８００℃空气中进行了恒温氧化和循环氧化研究，通过热重分析和扫描电镜测试，发现注钇后Ｉｎｃｏｎｅｌ７１８合金的抗恒温氧化及抗循环氧化性能显著提高．并且，随
New tetraazamacrocyclic ligand with 1, 4, 7, 10-tetrakis (4-nitrobenzyl) pendent groups (C36H40N8O8, Mr= 712.76) crystallized in the monoclinic system, P21/n sp
利用直接解调方法分析COMPTEL VP1数据, 得到了脉冲星Geminga10—30 MeV脉冲辐射存在的证据: 全位相及分位相成像均得到了Geminga.分位相成像结果显示,光变曲线的峰值位于pul
由于现代社会速度的加快、提高经济效益、保证工程质量，具有决定性作用。本文主要针对道工程施工中进度控制系统的多个问题；根据不同系统进行深入分析，同时结合国家标准，规范中相
A multilayer film of hemoglobin (Hb) molecules and polyelectrolyte sulfonate were fabricated on a thiol self-assembled monolayers (SAMs) by electrostatic force.