Stereospecific polymerizations of 1,3-butadiene catalyzed by Co(II) complexes ligated by 2,6-bis(benzimidazolyl)pyridines

Synthesis, characterization, and butadiene polymerization of iron(III), iron(II) and cobalt(II) chlorides bearing 2,6-bis(2-benzimidazolyl)pyridyl or 2,6-bis(pyrazol)pyridine ligand

“…While for those supported by s-donating phosphine ligands, the mainly 1,2-selectivity [19,24,28] is generated when the coordinated monomer preferentially attacks the third carbon to the last. The N, N, N-tridentate ligand reported here as well as previously published [12,39,42,62,63] may also serve to design appropriate new ligand framework for cis-and/or trans-1,4 selective polymerization of butadiene.…”

“…The exceptional performance of such ligand set in olefin polymerization may also be relevance to butadiene area and catalytic performance of transition metals bearing such set of ligands for butadiene polymerization, however, is less established [12,13,15,62,63]. We have reported the high active 2,6-bis(imino)pyridyl ligands ligated transition complexes for selectivity-controlled polymerization of butadiene [39,42,43], and found the selectivity could be manipulated within a wide range, from high cis-1,4 (97.0%) to high trans-1,4 (95.4%) just by either altering the metal center or modifying the ligand environments.…”

Pyridine–oxazoline and quinoline–oxazoline ligated cobalt complexes: Synthesis, characterization, and 1,3-butadiene polymerization behaviors

“…It is noteworthy that the thermal stability of the active species generated by 7b was even higher than 6b; the polymer yield was still up to 87% even at a high temperature of 80 °C . This result is in contrast [43,44]. The high thermal stability might be due to the rigid structure backbone which protected the active centre [45,46].…”

1,3‐butadiene polymerization using Co/Nd‐based Ziegler/Natta catalyst: Microstructures and properties of butadiene rubber

“…This implied that the Co/Nd mixed catalyst system showed some unique properties for producing a BR structure with high cis21,4 and low vinyl21,2 contents from Nd species and low trans21,4 structure induced by the Co portion [1,16]. For Mw and MWD of the (Co/Nd)-BR, an increase in the amount of Co in the mixed catalyst solution decreased the Mw of BR from 8.25 3 10 5 to 7.33 3 10 5 when the molar Co/Nd ratio increased from 0/1 to 0.5/0.5 due to the effect of the Co catalyst producing BR with high branches and low Mw [5].…”