isotactic poly (1-butene), ipbu-1, was synthesized by using a metallocene catalyst. the thermodynamic phase behavior of polymer–organic solvents systems is very important in every polymer application.  in this paper, the solid–liquid equilibrium of ipbu-1 with different organic solvents (1-heptyne, cyclo octane) was studied by a mathematical model. by considering the experiments temperature-mol...

Porous organic polymers (POPs) are widely used in various areas such as adsorption, separation and catalysis. In the present work, ionic liquid-modified porous (IL-POPs) synthesized by dispersion polymerization were applied to immobilize metallocene catalysts for olefin polymerization. The prepared IL-POPs characterized Fourier transform infrared spectrometer (FT-IR), nitrogen sorption porosime...

Albert J. van Reenen and Omar Sultan Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa Reprint requests to Dr. A. J. van Reenen. Fax: +27-21-8084967. E-mail: [email protected] Z. Naturforsch. 2007, 62b, 362 – 366; received November 1, 2006 Dedicated to Prof. Helgard G. Raubenheimer on the occasion of his 65th birthday TwoC2-symmet...

Non-bridged half-metallocene dimethyl complexes of group 4 metals 2a-4a with an N-4-methoxyphenyl(iminomethyl)pyrrolyl ligand 1a were synthesized and characterized by NMR spectroscopy and X-ray analysis. Upon activation with [Ph3C][B(C6F5)4], these complexes became active catalysts for the polymerization of 1-hexene. A series of hafnium complexes with various N-substituents on the imine group o...

Reduction of Zr(IV) metallocenium cations with sodium amalgam (NaHg) produces EPR signals assignable to Zr(III) metallocene complexes. The chloro-bridged heterodinuclear ansa-zirconocenium cation [(SBI)Zr(μ-Cl)2AlMe2](+) (SBI = rac-dimethylsilylbis(1-indenyl)), present in toluene solution as its B(C6F5)4(-) salt, thus gives rise to an EPR signal assignable to the complex (SBI)Zr(III)(μ-Cl)2AlMe...

A series of dinitrogen-bridged dimolybdenum-dinitrogen complexes bearing metallocene-substituted PNP-pincer ligands is synthesized by the reduction of the corresponding monomeric molybdenum-trichloride complexes under 1 atm of molecular dinitrogen. Introduction of ferrocene as a redox-active moiety to the pyridine ring of the PNP-pincer ligand increases the catalytic activity for the formation ...