Strict morphological control over growing polymer particles is an indispensable requirement in many catalytic olefin polymerization processes. In catalysts with mechanically stronger supports, e. g., polymerization-grade silicas, the emergence of extensive cracks via sectioning fragmentation mechanism requires severe stress build-up polymerizing catalyst particle. Here, we report on three facto...

This study presents methods for treating a kind of nanoclay and investigates the effects of methylaluminoxane (MAO) exposure time and or dodecylamine (DDA) reflux time on in-situ polymerization of ethylene in the presence of nanoclay and examines the morphology and properties of the prepared polyethylene/clay nanocomposites. The results revealed that by increasing MAO exposure time productivity...

The oligomerisation of ethylene to linear alpha olefins is an important industrial process for the production of polyethylene co-monomers, plasticizers, surfactants and waxes. With the ever increasing market demand for short chain linear alpha ole fins (1-butene, 1-hexene and 1-octene) there has been intensive research in both industry and academia on methods to selectively oligomerise ethylene...

ansa-Indenylamidodimethyltitanium complex ([t-BuNSiMe2Ind]TiMe2: 1) was synthesized by one-pot reactions starting from the ligand, MeLi and TiCl4. The structure of 1 was determined by X-ray crystallography and the results obtained revealed that the indenyl ligand coordinate to titanium in an η-tendency. Propylene polymerization was conducted with 1 in toluene or heptane as solvent at 0 ̊C in th...

Reductions of imine compounds 2-methoxy-N-(1-(pyridin-2-yl)ethylidene)ethanamine (L1), 2-methoxy-N-((pyridin-2-yl)methylene)ethanamine (L2), N,N-diethyl-N-((pyridin-2-yl)methylene)ethane-1,2-diamine (L3) and 2-((pyridin-2-yl)methyleneamino)ethanol (L4) using NABH4 produced their corresponding amine analogues N-(2-methoxyethyl)-1-(pyridin-2-yl)ethanamine (L1a), 2-methoxy-N-((pyridin-2-yl)methyl)...

Aluminum oxide encapsulated high-permittivity (ε) BaTiO3 and ZrO2 core-shell nanoparticles having variable Al2O3 shell thicknesses were prepared via a layer-by-layer methylaluminoxane coating process. Subsequent chemisorptive activation of the single-site metallocene catalyst [rac-ethylenebisindenyl]zirconium dichloride (EBIZrCl2) on these Al2O3-encapsulated nanoparticles, followed by propylene...

Binary mixtures of Cp2ZrMe2, Cp2ZrCl2, dimethylaluminum chloride, trimethylaluminum, and methylaluminoxane (MAO), as well as Cp2ZrMe2 with boron-based activators, have been studied by in situ IR spectroscopy (Cp = cyclopentadienyl, Me = methyl). The position of a strong band near 800 cm(-1), corresponding to the out-of-plane vibration of the Cp hydrogen atoms, is sensitive to the bonding enviro...

Catalytic polymerization of styrene with a series of dinuclear nickel(II) complexes [{Ni(acac)}2{μ-C6H2-(N-Ph-R)4}] (R = 4-Et (1a), 4-OEt (1b), 2-OEt (1c), 2-Et (1d), and 2,6-Et2 (1e)) in the presence of methylaluminoxane was studied under various conditions to evaluate the substituent effect. The activity of 1a-1e, except 1c, increased with an increase in the reaction temperature, and the high...

The 2-benzazole-1,10-phenanthrolines and their chromium(III) complexes were synthesized and characterized by elemental and spectroscopic analyses as well as by single-crystal X-ray crystallography. X-Ray crystallographic analyses of C6 and C8 reveal an octahedral geometry around both chromium centers. The electronic spectra of the chromium complexes exhibit d-d transitions typically of a pseudo...