Polymerization of 1,3‐alkadienes in the presence of Ni‐ and Ti‐based catalytic systems containing methylalumoxane

Crystallization and melting behavior of 1,2‐syndiotactic polybutadiene

“…1,2 Highly cis-1,4 polybutadiene was prepared with Co(acac) 3 -MAO, 1 Ni(acac) 2 -MAO, 3,4 and catalysts based on Nd(allyl) compounds. 5 1,2-Syndiotactic polybutadiene and 3,4-polyisoprene, having an essentially syndiotactic structure, were obtained with catalysts based on iron(II) complexes with aromatic bidentate amines (i.e., bipyridine phenanthroline) and methylaluminoxane 6,7 and with the system CrCl 2 (dmpe) 2 -MAO.…”

C2-Symmetric Zirconocenes in the Polymerization of Conjugated Diolefins

“…the chemical shifts of the resonances observed in the 13 C NMR spectrum ( Figure 1a) and the data reported in the literature. [4,8,16] Moreover, the structure was corroborated by observing the resonance of the chemically equivalent methylene protons, that is a deceptive triplet (see 1 H NMR spectrum, Figure 1b). The polymer obtained in run 3 is crystalline, with a melting point at 98 8C.…”

Stereospecific Olefin Polymerization Catalyzed by Metallocene Complexes

“…Titanium [153] and vanadium [154] monocyclopentadienyl complexes are known to serve as catalysts for 1,4-cis polymerization, although bis(cyclopentadienyl) complexes are less active [155]. Ricci et al investigated various diene monomers using CpTiCl 3 -MAO catalysts and showed that stereoselectivity of polymerization depends on the monomer employed [156].…”