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Structure of active centers, their stereospecificity distribution, and multiplicity in diene polymerization initiated by NdCl3‐based catalytic systems

“…Therefore, we performed quantum-chemical calculations of the geometry and electronic structure ofand -states of six ACs. Six types of ACs that may be present in the NdCl 3 ⅐ 3TBP-Al(iso-C 4 H 9 ) 3 catalytic system are schematically shown in Figure 1.…”

“…Here, the object is to perform the quantum-chemical study of the electronic structure and geometry of the potential ACs, to estimate their steoreospecificity, and to interpret the data on the microstructure of polybutadiene (PB) prepared in the presence of NdCl 3 ⅐ 3TBP-Al(iso-C 4 H 9 ) 3 , NdCl 3 ⅐ 3TBP-Mg(n-C 4 H 9 )(iso-C 8 H 17 ); NdCl 3 ⅐ 3TBP-Al(iso-C 4 H 9 ) 3 -Mg(n-C 4 H 9 )(iso-C 8 H 17 ), and NdCl 3 ⅐ 3TBP-Mg(n-C 4 H 9 )(iso-C 8 H 17 )-Al(iso-C 4 H 9 ) 3 .…”

Highly trans-Stereospecific Isoprene Polymerization by Neodymium Borohydrido Catalysts

“…Bimetallic Nd-Mg associations have been frequently observed [38][39][40] or postulated 15,41 when a magnesium derivative is reacted with a lanthanide complex. It was therefore assumed that bridging Ln(-BH 4 )Mg species could be formed and NMR experiments were undertaken to focus on that point.…”

Copolymerization of 1-hexene and 1-dodecene with 1,3-butadiene by a versatate/diisobutylaluminum hydride/t-butyl chloride catalyst system

“…Moreover, the copolymerization conditions, such as reaction time (2 hours The literature [10][11][12][13] shows several possible structures for active sites ( Figure 1) formed from the catalytic system used in this work. The existence of these different types of active sites does not mean they all are present at the same time.…”

“…When 1-dodecene was used as comonomer, the reduction in the conversion was so significant that no [10][11][12][13] . Silva, G. M. et al -Copolymerization of 1-hexene and 1-dodecene with 1,3-butadiene by a versatate/diisobutylaluminum hydride/t-butyl chloride catalyst system polymer was formed when about 10% wt of 1-dodecene was added.…”