Homopolymerization of Ethylene, 1-Hexene, Styrene and Copolymerization of Styrene With 1,3-Cyclohexadiene Using (h5-Tetramethylcyclopentadienyl)dimethylsilyl(N-Ar’)amido-TiCl2/MAO (Ar’=6-(2-(Diethylboryl)phenyl)pyrid-2-yl, Biphen-3-yl)

Abstract

The propensity of a half-sandwich (η5-tetramethylcyclopentadienyl)dimethylsilylamido TiIV-based catalyst bearing an auxiliary diethylboryl-protected pyridyl moiety (Ti-8), activated by methylaluminoxane (MAO) to homopolymerize α-olefins such as ethylene, 1-hexene and styrene as well as to copolymerize styrene with 1,3-cyclo-hexadiene is described. The reactivity of Ti-8 was investigated in comparison to a 6-(2-(diethylboryl)phenyl)pyrid-2-yl-free analogue (Ti-3).

(nBuCp)2ZrCl2‐catalyzed ethylene‐4M1P copolymerization: Copolymer backbone structure, melt behavior, and crystallization

“…The active catalytic species in Copolymerization A (pseudo-homogeneous polymerization) and Copolymerization B (slurry-heterogeneous polymerization) are the following two ion pairs: (1) Table 2. For nonmetallocene precatalysts, depending on the metal-ligand relation, predominantly secondary 79,80 or, both primary and secondary 81,82 insertions may occur. However, in Copolymer A, the exclusive formation of ethylene-rich homopolymer backbones, in addition to the co-insertion of ethylene and 4M1P, prevailed.…”

Novel cationic rare earth metal alkyl catalysts for precise olefin polymerization

“…In 2004, Yasuda and coworkers described the random copolymerization of isoprene with norbornene by a nickel‐based catalyst, obtaining norbornene‐rich (62–95 mol %) isoprene/norbornene copolymer with predominant 1,4‐isoprene microstructure . In 2008, Hou and coworkers reported the incorporation of norbornene (33–88 mol %) into 3,4‐predominant polyisoprene (3,4‐selectivity up to 70%) by a [C 5 Me 4 (SiMe 3 )]Sc(η 3 ‐CH 2 CHCH 2 ) 2 /activator binary system . To compare the copolymerization behavior of the tropidinyl scandium catalyst 4a , copolymerizations of isoprene and norbornene were carried out with different monomer proportions by us in 2014 [Fig.…”

Aminopyridine stabilized group-IV metal complexes and their applications

“…16). The yield of the ligand is good enough; however, the yield of the complex is lower [63][64][65].…”

“…The activity of Cp 2 TiCl 2 enhanced to 424 kg PE cat mol -1 h -1 when small amount of water was added due to the formation of methyl aluminoxane (MAO) by the hydrolysis of Al-alkyls . Industrial applications of metallocene-based catalysts have been tremendous; however, their limitations, for example, very high costs and inability to polymerize polar olefins, have forced the researches for alternatives, and amido ligands have been the most notable success because: (1) these ligands make two bonds with the metal resulting into a fourmembered chelate ring system and (2) they enable the incorporation of variety of functionality in remaining two substituents on N-atom and hence to dictate variety in their reactivity and selectivity (Scheme 1) [28,29,[51][52][53][54][55][56][57][58][59][60][61][62][63][64][65]. Aminopyridinato ligands could be derived from deprotonated 2-aminopyridines, critical sub-class of amido ligands, which could provide additional advantages due to their binding modes flexibility.…”