Metal complex bicenter catalysts for olefin and diene polymerization

Structure of Polybutadienes Synthesized with a New Catalyst System, 2. Blends oftrans-andcis-1,4-Polybutadiene

“…Then, a metalaluminium organic complex bearing oligodienyl ligands was synthesized by the exchange reaction between MtCl m (Mt = nickel or zirconium, m = 2 or 4) and Al(i-C 4 H 9 ) 3 in the presence of allenes or dienes. On the basis of IR-and chromatomass spectrometric data, [3] it was found that the structure of the metal-aluminium organic complex is as follows:…”

“…[2] Only recently, [1,3] polybutadienes have successfully been synthesized for the first time using SiO 2 -supported titanium-magnesium catalysts and titanium-magnesium catalysts modified by organo-metallic compounds of nickel or zirconium. Previously, [4,5] these binuclear catalytic systems (BCS) were Full Paper: The structure, composition and temperature behaviour of polybutadienes prepared with binuclear metal complex catalysts immobilized on a solid carrier are investigated by differential scanning calorimetry, infra-red spectroscopy and X-ray scattering.…”

“…Moreover, the consumption of the second component of the catalysts (in this case the organo-aluminium complex) decreases by nearly an order of magnitude. [3] We are not aware of other reports in the scientific literature on the use of titanium-magnium catalysts for polymerization of dienes. Meanwhile, the same BCS also exhibit appreciably higher activity (as compared with traditional catalysts) on polymerization of polydienes, in particular on synthesis of PB and polyisoprenes.…”

“…Then, a metalaluminium organic complex bearing oligodienyl ligands was synthesized by the exchange reaction between MtCl m (Mt = nickel or zirconium, m = 2 or 4) and Al(i-C 4 H 9 ) 3 in the presence of allenes or dienes. On the basis of IR-and chromatomass spectrometric data, [3] it was found that the structure of the metal-aluminium organic complex is as follows:where R = C 4 H 6 , C 5 H 8 , or C 3 H 4 ; n = 2-6.Oligomers of diene or allene stabilize the organo-metallic complex due to formation of p -bonds between the metal and the organic ligands; the oligoalkyldiene ligand was obtained on the basis of allene, and the oligodienyl one on the basis of butadiene or isoprene.To identify the nascent structure of the polymer, we studied the samples isolated from polymerization as powders compressed to 0.5 mm-thick sheets at ambient temperature. Samples are mounted in the holder of an X-ray instrument equipped with a heating attachment.…”

Structure of Polybutadienes Synthesised with a New Catalyst System, 3. Random Copolymers oftrans-1,4- and 1,2-Polybutadiene

“…[11] Virtually completely regular TPB was prepared using silica-gel supported, and metal-complex modified, titanium-magnesium catalysts according to the literature, [12] where the polymerization technique is described in detail.…”