Lanthanide compounds—Catalysts of stereospecific polymerization of diene monomers. Review

Soluble neodymium chloride 2-ethylhexanol complex as a highly active catalyst for controlled isoprene polymerization

“…NdCl 3 $3 i PrOH/AlEt 3 could display the behavior of a quasiliving polymerization only at À70 C, but the chain transfer occurred violently as the temperature increased [14]. Dong et al [15e17] prepared polyisoprene with narrow molecular weight distribution (M w /M n < 2.0) using MAO-activated Nd(O i Pr) 3 catalyst, but did not reported the catalyst for living polymerization. Up to now, living polymerization using Nd-based catalysts activated by AlR 3 at room temperature or above remains blank.…”

“…naphthenate and versatate), AlR 3 (e.g. Al(i-Bu) 3 , Al(i-Bu) 2 H and AlEt 3 ) and a chloride-containing compound (e.g. AlEt 2 Cl, t-BuCl and Me 2 SiCl 2 ).…”

Synthetic rubbers prepared by lanthanide coordination catalysts

“…The crystal has catalytic activity for butadiene polymerization (butadiene/Nd = 5 × 10 4 g butadiene/mol Nd, 50 …”

Enhancement of the activity of a neodymium catalyst for the synthesis of stereoregular polyisoprene

“…Catalytic systems formed by the reaction of lanthanide chloride (catalyst) with an organoaluminum compound (cocatalyst) exhibit low activity in diene polymerization [1,2]. The catalyst activity is considerably enhanced on introducing electron-donor compounds [2].…”

“…The catalyst activity is considerably enhanced on introducing electron-donor compounds [2]. An electrondonor ligand increases the extent of the covalence of the lanthanide-halogen bond and thus favors alkylation with an organoaluminum compound with the formation of lanthanide-carbon bonds active in polymerization [1,2].…”