【摘 要】
：
By treating disodium(thiophenedimethylene)dicyclopentadienide C4H2S(CH2C5H4Na)2 with two equivalent of CpTiCl3 or CpZrCl3 DME at 0℃ in THF, two new thiophenedi
【机 构】
：
Department of Chemical Engineering
论文部分内容阅读
By treating disodium(thiophenedimethylene)dicyclopentadienide C4H2S(CH2C5H4Na)2 with two equivalent of CpTiCl3 or CpZrCl3 DME at 0℃ in THF, two new thiophenedimethylene bridged binuclear metallocenes [Cl2MC5H5][C5H4CH2C4H2SCH2C5H4][C5H5MCl2] (M = Ti 3, M = Zr 4) were synthesized in high yield and their structures were characterized by 1H-NMR. These complexes were used as catalysts for ethylene polymerization in the presence of methylaluminoxane (MAO). The effects of polymerization temperature, time, concentration of catalyst, molar ratio of MAO/Cat on polymerization were studied in detail. The catalytic activities of thiophenedimethylene bridged binuclear are higher than that of pheneyldimethylene bridged binuclear metallocene catalysts and much higher than that of corresponding mononuclear metallocenes (Cp2TiCl2 and Cp2ZrCl2). The molecular weight distribution curves of polyethylenes produced by binuclear metallocene catalysts (3, 4) and by mononuclear metallocene catalyst have only single peak, but the former (MWD = 3.5-4.7) is obviously broader than the latter (MWD = 2.0-2.2).
其他文献
The article is concerned with oscillation of nonautonomous neutral dynamic delay equations on time scales. Sufficient conditions are established for the existen
We present an extended F-expansion method for finding periodic wave solutions of nonlinear evolution equations in mathematical physics. By using extended F-expa
In this paper, ethylenebisformamide was synthesized and used as a novel plasticizer for cornstarch to prepare thermoplastic starch (TPS). FT-IR expressed that e
Linear Thomson scattering of a short pulse laser by relativistic electron has been investigated using computer simulations. It is shown that scattering of an in
A new exponential-type weighted implicit difference scheme for solving the Burgers equation was developed and iterated by using the Alternating Group Explicit (
The electron impact(EI) time-of-flight mass spectra(TOFMS) of the title compounds(thioxo-Biginelli compounds) were studied to establish their fragmentation path
In this article, the author studies the initial-(Dirichlet) boundary problem for a high-field version of the Schr(o)dinger-Poisson equations, which include a no
Regioselective decomposition of 11-substituted-16α,17α-methyleneazopregna-1,4-dien-3, 20-dione I proceeded smoothly through thermal decomposition in the prese
In this paper, we introduce the notion of a (2+1)-dimensional differential equation describing threedimensional hyperbolic spaces (3-h.s.). The (2+1)-dimensiona
This note gives an explicit lower bound of the function ψ(t) in the lemma of DiPerna and Chen and some remarks.