Highly efficient terpolymerizations of ethylene/propylene/ENB with a half-titanocene catalytic system

Abstract

Highly efficient terpolymerization of ethylene, propylene and 5-ethylidene-2-norbornene using a half-titanocene containing iminoimidazolidine with methylaluminoxane/Al(iBu)3/2,6-ditertbutyl-4-methyl-phenol was achieved.

Imidazolidin-2-iminato vanadium complexes for the synthesis of ethylene/propylene/5-ethylidene-2-norbornene (ENB) terpolymers with high ENB incorporation and ultra-high molecular weight

“…8 and the assignments are given according to the literature. 38,42 Similar to the 1 H NMR spectra of terpolymers prepared by using half-titanocene catalysts, the wide signals around 5.24 ( a E ) and 5.02 ( a Z ) ppm assigned to the protons of the internal double bond with E and Z configurations in the ENB units were observed. 38 Moreover, the signals of protons (i) in ENB units appeared at 2.74 (for the Z configuration) and 2.40 (for the E configuration) ppm, respectively.…”

“…38,42 Similar to the 1 H NMR spectra of terpolymers prepared by using half-titanocene catalysts, the wide signals around 5.24 ( a E ) and 5.02 ( a Z ) ppm assigned to the protons of the internal double bond with E and Z configurations in the ENB units were observed. 38 Moreover, the signals of protons (i) in ENB units appeared at 2.74 (for the Z configuration) and 2.40 (for the E configuration) ppm, respectively. The molar ratio of the E configuration to the Z configuration of ENB units in the resulting copolymer was calculated to be ∼4.0 by using the ratio of the integral values of the peaks at 2.40 ppm and 2.74 ppm or the peaks at 5.24 and 5.02 ppm.…”

“…The imidazolidin-2-iminato ligands can be expected to act as 2σ,4π electron donors, and have been widely used in the preparation of vanadium and titanium complex catalysts with high performance in olefin polymerization. 35–40 For example, the imido vanadium complexes containing imidazolidin-2-iminato ligands have been reported for ethylene polymerization with high catalytic activity. 40 However, the catalytic activity decreased obviously in the copolymerization of ethylene with norbornene, which might be attributed to the bulky imido ligand.…”

“…40 However, the catalytic activity decreased obviously in the copolymerization of ethylene with norbornene, which might be attributed to the bulky imido ligand. 38 The vanadium complexes ( V1–V4 ) containing N-heterocyclic carbene (NHC) ligands and vanadium complexes ( Vi1–Vi4 ) containing imidazolidin-2-iminato ligands are shown in Chart 1. The catalytic behavior of the novel vanadium complexes Vi1–Vi4 toward ethylene/propylene copolymerization and ethylene/propylene/ENB terpolymerization were investigated.…”

Exploring Green Route of Cross-Linking for Bio-Based Ethylene Propylene Diene Rubber: A Step toward Circular Economy

“…Figure displays the comparative 1 H NMR spectra of EPDM and e-EPDM. The protons of the double bonds with E and Z configurations of ENB parts exhibit signals at about 5.26 and 5.03 ppm in the 1 H NMR spectrum of EPDM rubber . The epoxidation reaction converted the double bonds of ENB units into epoxy rings.…”