Ligand-regulated polymerization of conjugated dienes catalyzed by confined iminopyridine iron complexes with high activity and thermal stability

Zhu, Guangqian; Wang, Liang; Mahmood, Qaiser; Zhou, Li; Wang, Qinggang

doi:10.1016/j.polymertesting.2021.107317

Cited by 14 publications

(29 citation statements)

References 48 publications

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“…We speculate that this phenomenon may be related to steric hindrance. 52 When the ratios of Bd/ Co3 were increased from 25 000 to 50 000, a higher molecular (3.12 × 10 5 to 4.94 × 10 5 ) weight and a narrower PDI (5.22 to 2.77) were observed (Table 2 run 4 and Table 4, Co1 ).…”

Section: Resultsmentioning

confidence: 95%

Ultrahigh activity and broad temperature resistance of amine–imine cobalt precatalysts for butadiene polymerization

Fu,

Tang,

Hua

2023

Dalton Trans.

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Section: Resultsmentioning

confidence: 95%

Ultrahigh activity and broad temperature resistance of amine–imine cobalt precatalysts for butadiene polymerization

Fu,

Tang,

Hua

2023

Dalton Trans.

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“…In addition, other studies also indicate the high reactivity of trans-β-farnesene, using different catalytic systems to perform the homopolymerization and copolymerization of this renewable monomer. [8,16] The dispersity of the produced polymer, on the other hand, showed variability according to the experimental conditions. In reactions where the ratio n Al =n Nd was higher (F3 60…”

Section: Trans-β-farnesene Coordination Polymerizationmentioning

confidence: 99%

“…The dispersity (D) is calculated as the ratio between the M w and M n , and the monomer conversion (x) is obtained as the ratio between the concentration of mers incorporated into polymer chains and the initial monomer concentration, as one can see in Equation (15). The MMD is calculated using the molar concentration of living and dead polymer chains according to Equation (16).…”

Section: Chain Initiationmentioning

confidence: 99%

“…However, according to Bahena et al, [8] the synthesis of this polyterpene with high performance requires control over its micro and macrostructure, which can be achieved only by anionic polymerization, [9] nitroxide mediated radical polymerization, [2,3,10,11] and coordination polymerization. [8,[12][13][14][15][16][17] Thus, most studies performed the polymerization of trans-β-farnesene and the copolymerization of trans-β-farnesene with other monomers, such as styrene, ethylene, and butadiene through the coordination polymerization technique, using different catalytic systems based on iron, [12,15,16] titanium, [17] and neodymium. [8,13,14] In all cases, high catalytic activities and polymers with high stereoselectivity, rich in 1,4-cis or 1,4-trans contents, have been described.…”

Section: Introductionmentioning

confidence: 99%

“…Zhu et al [16] developed a series of confined iminopyridine-iron complexes combined with the cocatalyst methylaluminoxane (MAO), forming catalytic systems that showed high catalytic activity and thermal stability in the polymerization of isoprene, β-myrcene, and trans-β-farnesene. In addition, the catalytic system presented moderate regioselectivity and high control of stereoselectivity.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Modelling and parameter estimation of trans‐β‐farnesene coordination polymerization

Sá

Córdova²,

Melo

et al. 2023

Can J Chem Eng

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trans‐β‐Farnesene is a bio‐derived terpene monomer that can polymerize, generating polymers with properties that can be similar to the properties of conventional petroleum‐derived polymers. For this reason, in the present study, several coordination polymerizations of trans‐β‐farnesene are carried out using the Ziegler–Natta catalyst system composed by neodymium versatate (NdV3), diisobutylaluminum hidride (DIBAH), and dimethyldichlorosilane (DMDCS) in order to evaluate the influence of key operation variables on the control of average molar masses and monomer conversion. A phenomenological model is proposed to describe the coordination polymerization of trans‐β‐farnesene, and the kinetic parameters required to simulate the reactions are estimated. The initial concentration of DIBAH used as a chain transfer agent (CTA) is calculated by a data reconciliation procedure since this very active compound can participate in undesired side reactions. It is shown that the initial monomer, DIBAH, and NdV3 concentrations exert strong influences on the monomer conversion and average molar masses of (poly)farnese while the temperature effect is not so pronounced. The proposed kinetic mechanism was able to predict well the experimental data collected during the reactions, with the successful reconciliation of CTA concentrations and estimation of model parameters.

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Unveiling the mutual effects of hydroxyl and dibenzhydryl groups in α‐diimino‐nickel precatalysts for direct synthesis of polyethylene elastomers

Wang,

Qin,

Mahmood

et al. 2024

Applied Organom Chemis

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The properties and practical applications of polyethylene are closely associated with the polymer molecular weight, polydispersity, degree of branching, and the type of branches and its arrangement within microstructure. In this study, a set of structurally diverse unsymmetrical 1‐(2,6‐dibenzhydryl‐4‐hydroxylphenylimino)‐2‐(2,6‐(R)‐4‐(R1)phenylimino)acenaphthene‐nickel dibromide precatalysts (where Ni2Me [R = Me, R1 = H], Ni2Et [R = Et, R1 = H], Ni2iPr [R = iPr, R1 = H], Ni3Me [R, R1 = Me], Ni2Et,Me [R = Et, R1 = Me]) has been prepared and studied for ethylene polymerization. Molecular structure analysis of Ni2Me and Ni2Et complexes revealed distorted tetrahedral geometries at nickel. The polymerization activities are extremely high for all precatalysts upon activation with either EASC or MMAO aluminum reagents, a trend notably pronounced in the case of the EASC‐activated systems, entering activity in the range of 10 million g mol−1 h−1 at 30°C. The Ni2Me demonstrated exceptional performance at higher temperatures, achieving an activity of 2.4 × 106 g mol−1 h−1 at 100°C and generated high molecular weight polyethylene (Mw = 105 g mol−1) with narrow polymer dispersity across all reaction temperatures (Ð ≈ 1.5). High temperature 13C NMR spectra identified 97–142/1000C branches in resulting polyethylene, a feature significantly dependent on the reaction temperature. In terms of mechanical properties, stress–strain analysis indicated that polyethylene synthesized at lower temperatures displayed superior tensile strength compared with that produced at higher reaction temperatures, while a reverse trend was observed in strain recovery analysis. The high strain recovery (up to 72%) of these polyethylene highlights the characteristic properties of thermoplastic elastomers.

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Ligand-regulated polymerization of conjugated dienes catalyzed by confined iminopyridine iron complexes with high activity and thermal stability

Cited by 14 publications

References 48 publications

Ultrahigh activity and broad temperature resistance of amine–imine cobalt precatalysts for butadiene polymerization

Ultrahigh activity and broad temperature resistance of amine–imine cobalt precatalysts for butadiene polymerization

Modelling and parameter estimation of trans‐β‐farnesene coordination polymerization

Unveiling the mutual effects of hydroxyl and dibenzhydryl groups in α‐diimino‐nickel precatalysts for direct synthesis of polyethylene elastomers

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