Heterogenization Strategies for Nickel Catalyzed Synthesis of Polyolefins and Composites

Accounts of Materials Research, Journal Year: 2023, Volume and Issue: 4(6), P. 496 - 506

Published: May 20, 2023

ConspectusPolyolefin is one of the most common synthetic polymers. However, polyolefins are nonpolar materials, which leads to poor compatibility with polar thus limiting their application in some fields. Polar functionalized can lead significantly improved dyeability, adhesiveness and fillers, realize customized properties polyolefin materials. Transition-metal-catalyzed coordination copolymerization olefin comonomers represents a direct potentially economic route synthesize polar-functionalized has attracted great attention recent decades. Literally hundreds nickel palladium catalysts have been synthesized investigated olefin-polar monomer achieve high efficiency by tuning molecular structures catalysts. In particular, earth-abundant low-cost nickel-based hold potential for industrial applications. research efforts focus on homogeneous catalysts, while industrially preferred heterogeneous systems remained largely unexplored. With objective bridging this gap, our group recently developed series heterogenization strategies synthesis high-performance taking advantage hydrogen bond anchoring, ionic coanchoring, cocatalyst, cluster formation. These involve known or easily accessible be adapted various catalytic systems, simultaneous enhancement all parameters such as thermal stability, activity, comonomer incorporation ratio, copolymer weight versus counterparts. addition, performance tuned changing type support, thereby facilitating discovery Most importantly, product morphology control achieved. This desirable polymerization processes because it avoids reactor fouling results significant improvements safety operational processes. Finally, these give access materials (polar-functionalized polyolefins, in-reactor blends polyolefin-based functional composites) custom-made properties. Compared melt blending, composites obtained situ better material By using prepared situ. applications many fields, electrical conductivity, photodegradation, flame retardancy, barrier, etc. It expected that continuous mechanism/catalysts, heterogenizatioin will eventually commercialization nickel-catalyzed production composites.

Language: Английский

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Heterogeneous Nickel Catalysts for the Synthesis of Ethylene-Based Polyolefin Elastomers

Macromolecules, Journal Year: 2024, Volume and Issue: 57(3), P. 1080 - 1086

Published: Feb. 1, 2024

Ethylene-based polyolefin elastomers (EPOEs) represent a novel class of material prepared using ethylene as the only feedstock and bear comparable mechanical elastic properties versus traditional (POEs). EPOEs are from late-transition-metal (nickel or palladium)-catalyzed chain walking polymerization ethylene. However, literature-reported potent catalysts homogeneous systems that operate at relatively low temperatures (<90 °C), while industrial production POE materials requires high (>120 °C). In this contribution, we install some OM (M = H, Na, K) tags in an α-diimine ligand framework, enabling facile heterogenization nickel complexes onto MgCl2-based solid support. The resulting heterogeneous highly active demonstrate much better thermal stability (up to 150 °C) than their counterparts. More importantly, polyethylene products super-stretchability 2160%) maintaining tensile strength 15.4 MPa) elasticity (strain recovery value up 83%). These EPOE can also be used toughen polypropylene, well compatibilize blends polypropylene.

Language: Английский

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Synthesis of Polar-functionalized Isotactic Polypropylenes Using Commercial Heterogeneous Ziegler–Natta Catalyst

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(10), P. 6837 - 6845

Published: March 1, 2024

The efficient synthesis of polar-functionalized polypropylenes with high molecular weight and stereoregularity represents a challenging task. This challenge becomes even more daunting when pursuing an industrially preferred heterogeneous process. study demonstrated the realization these goals through use commercial Ziegler–Natta catalysts in copolymerization propylene ionic cluster polar monomers. results revealed activity (∼1.1 × 107 g mol–1 h–1), moderate monomer incorporation ratios (∼4.9 mol %), copolymer (Mw > 105 mol–1), ([mmmm] ∼ 96%), melting temperature range (150–162 °C). utilization monomers improved thermal stability as well stereoselectivity catalyst. Moreover, catalyst can homopolymerize activities (>104 h–1). resulting isotactic (iPP) exhibited superior tensile strength, impact creep resistance, transparency, crystallinity compared nonpolar iPP. enhancement was attributable to dual roles unit, serving both transparent nucleating agent dynamic cross-linking functionality. Furthermore, iPP compatibility materials, offering benefits for applications composites, recycling mixed plastic wastes, 3D printing, other fields. offered comprehensive solution future industrial production via copolymerization, bridging gap between practical process from synthetic chemistry perspective enhanced material properties application perspective.

Language: Английский

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Synthesis, Characterization, and Catalytic Properties of Regioisomeric β‐Ketoimine Titanium Complexes for Ethylene Polymerization

Applied Organometallic Chemistry, Journal Year: 2025, Volume and Issue: 39(2)

Published: Jan. 1, 2025

ABSTRACT Non‐metallocene catalysts have shown great potential for modulating the polymer microstructure by changing ligand structure, but effects of structure and electronic property metal center on their catalytic performance remain underexplored. Herein, we designed synthesized two pairs isomeric tridentate β‐ketoimine complexes TiL a / b c d with methylthioaniline methylthioethylamine side arms, respectively, which exhibited moderate to extremely high activity over 10 6 g (mol Ti) −1 · h ·atm polymerization ethylene copolymerization α‐olefins (1‐hexene, 1‐octene) polar comonomer (9‐decen‐1‐ol) in presence MAO, activities order: > . The regioisomers arm showed significantly higher (co)polymerization than that arm, especially or 9‐decen‐1‐ol, indicating an obvious positive “comonomer effect”. complex highest insertion rate. Structural optimization using density functional theory (DFT) calculations suggested “side arms” properties titanium played key role copolymerization.

Language: Английский

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Synthesis of Graft‐Modified Polyolefin Compatibilizers for Compatibilizing Mixed Plastics

Chinese Journal of Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: April 11, 2025

Comprehensive Summary Recycling polyolefin and other plastic mixtures encounters significant obstacles due to the intricate nature economic inefficiencies of physically separating vast streams mixed waste. Incorporating compatibilizers emerges as a viable strategy diminish interfacial energy bolster compatibility, ultimately yielding homogeneous products. In this contribution, polar polyolefins featuring metal dynamic cross‐linking networks were synthesized by tandem polymerizing ionic cluster type monomers olefins. Subsequent treatment with HCl aqueous solution esterification polyester precursors yields high‐performance grafted for polymer compatibilizing. For PP/PC melting blends, adding 5 wt% graft‐modified results in tougher blends that surpass performance corresponding virgin iPP elongation at break (εb). Polar containing sodium carboxylate groups play dual role compatibilizing PET/HDPE acting both nucleating agents. Moreover, enables production comprising ternary polymers, which can be employed blends.

Language: Английский

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Self-immobilized polyolefin catalysts: A simple and transitional platform for heterogeneous olefin polymerization

Materials Today Chemistry, Journal Year: 2024, Volume and Issue: 35, P. 101898 - 101898

Published: Jan. 1, 2024

Language: Английский

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Enhanced catalytic ozonation of fiberboard wastewater using Ni-Cu co-doped Fe-ceramsite derived from sludge digestion residues

Journal of Cleaner Production, Journal Year: 2025, Volume and Issue: 503, P. 145390 - 145390

Published: April 1, 2025

Language: Английский

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Design and Synthesis of Bis-β-ketoimine Binuclear Titanium Complex Isomers to Probe Bimetallic Synergistic Effect for Ethylene Polymerization

Chinese Journal of Polymer Science, Journal Year: 2025, Volume and Issue: unknown

Published: April 7, 2025

Language: Английский

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Dual-Site Polymeric Heterogeneous α-Diimine Ni Catalysts with Tailored Spatial Distribution for Ethylene Polymerization

Macromolecules, Journal Year: 2023, Volume and Issue: 56(8), P. 3015 - 3023

Published: April 6, 2023

Dual-site molecular heterogeneous catalysts for synthesizing polyolefin in-reactor blends have received increasing attention in academia and industry. It is hypothesized that the mesoscopic spatial distribution of different catalyst molecules dual-site particles will significant impacts on superstructures properties blending products. difficult typical heterogenization to tune components particles. In this contribution, a self-supporting strategy based nickel-catalyzed precipitation coordination polymerization polar monomer was used achieve not only but also tuning catalytic polymeric These led higher activities compared with homogeneous catalysts. Moreover, they resulted high weights, good morphological control, improved compatibility materials. The composition physical blend can be controlled by molar ratio two components. Interestingly, it shown types result great differences thermal, mechanical, rheological applications obtained blends.

Language: Английский

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In-situ photo-crosslinkable elastomer based on polyalphaolefin/halloysite nanohybrid

Journal of Colloid and Interface Science, Journal Year: 2024, Volume and Issue: 659, P. 751 - 766

Published: Jan. 5, 2024

Language: Английский

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