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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Outer‐Shell Self‐Supported Nickel Catalysts for the Synthesis of Polyolefin Composites

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(18)

Published: March 3, 2023

In situ heterogeneous olefin polymerization has attracted much attention for the synthesis of polyolefin composites. However, complicated syntheses specially designed catalysts or detrimental effects interactions between catalyst and solid supports pose great challenges. this contribution, an outer-shell self-supporting strategy was to heterogenize nickel on different fillers via precipitation homopolymerization ionic cluster type polar monomer. These demonstrated high activity, good product morphology control, stable performances in ethylene copolymerization. Moreover, various composites with mechanical customized properties can be efficiently synthesized.

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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Noncovalent Ni–Phenyl Interactions Promoted α-Diimine Nickel-Catalyzed Copolymerization of Ethylene and Methyl Acrylate

Macromolecules, Journal Year: 2024, Volume and Issue: 57(11), P. 5279 - 5288

Published: May 20, 2024

As a widely used functional polyolefin, the industrial ethylene (E)-methyl acrylate (MA) copolymer (EMA), prepared by free radical polymerization under harsh conditions, is lightly branched with in-chain and terminal MA incorporation. Metal-catalyzed E/MA copolymerization as an alternative technique highly attractive challenging. Herein, we first report efficient direct using "sandwich" dibenzobarrelene-derived α-diimine nickel catalysts. The produced EMA copolymers in-chain, pendant, units have chain structure very similar to EMA, which not previously reported palladium Experimental results support that noncovalent Ni–phenyl interactions in catalysts promote copolymerization. Density theory studies clearly illuminate crucial role of well explain formation chain.

Language: Английский

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Preparation of polyethylene elastomers via controlled chain-walking ethylene polymerization for enhanced impact modification of polypropylene

Polymer, Journal Year: 2025, Volume and Issue: unknown, P. 128042 - 128042

Published: Jan. 1, 2025

Language: Английский

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Synthesis and Characterization of Multifunctional Chitosan-Grafted Hydrogel for Controlled Drug Delivery and Electrochemical Applications

Journal of Drug Delivery Science and Technology, Journal Year: 2025, Volume and Issue: unknown, P. 106770 - 106770

Published: March 1, 2025

Language: Английский

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Nickel‐ and Palladium‐Catalyzed Copolymerizations of Norbornene with Polar α‐Olefins

ChemCatChem, Journal Year: 2024, Volume and Issue: unknown

Published: March 26, 2024

Abstract Recent progress regarding the copolymerization of norbornene with various polar α‐olefins catalyzed by nickel and palladium catalysts is reviewed here special attention paid to diverse catalyst frameworks, monomer scopes as well polymer microstructures. Both influences steric effect electron property ligand substituents type monomers on catalytic behaviors (activity, stability, polarity tolerance, etc.) microstructures (molecular weight distribution, comonomer contents, have been summarized. The introduction noncyclic‐olefins, such vinyl monomers, higher α‐olefins, styrenes, into rigid cyclic‐based polynorbornene chain resulted in significant modifications polarity, compatibility, thermostability, processibility, transparency, many other properties material, which has also discussed review. contents this review classified according involved copolymerization, each section included bearing different structures, will be meaningful for development new types families norbornene‐based cyclic olefin copolymer materials future.

Language: Английский

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Noncovalent Interactions in Late Transition Metal-Catalyzed Polymerization of Olefins

Macromolecules, Journal Year: 2024, Volume and Issue: 57(15), P. 6899 - 6913

Published: July 23, 2024

Language: Английский

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Unveiling the Detailed Mechanism and Origins of Chemo-, Regio-, and Stereoselectivity of Rare-Earth Catalyzed Alternating Copolymerization of Polar and Nonpolar Olefins

Inorganic Chemistry, Journal Year: 2024, Volume and Issue: 63(7), P. 3544 - 3559

Published: Feb. 3, 2024

The direct copolymerization of polar and nonpolar olefins is great interest significance, as it the most atom-economical straightforward strategy for synthesis functional polyolefin materials. Despite considerable efforts, precise control monomer-sequence their regio- stereochemistry full challenges, related mechanistic origins are still in infancy to date. Herein, studies on model reaction Sc-catalyzed co-syndiospecific alternating anisylpropylene (AP) styrene were performed by DFT calculations. results suggest that subtle balance between electronic steric factors plays an important role during monomer insertions, a new amino-dissociated mechanism was proposed AP insertion at chain initiation. follows 2,1-si-insertion pattern, which mainly controlled caused restricted MeO···Sc interaction. As insertion, prefers 2,1-re-insertion manner its stereoselectivities influenced repulsions inserting polymer or ligand. More interestingly, found determined "steric matching" principle, quantitatively expressed buried volume metal center preinserted species. concept pocket has been successfully applied explain different performances several catalysts other reactions. insightful findings quantitative present here expected promote rational design rare-earth developing regio-, stereo-, sequence-controlled specific olefins.

Language: Английский

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Phosphonium-Catalyzed Monoreduction of Bisphosphine Dioxides: Origin of Selectivity and Synthetic Applications

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(13), P. 9335 - 9346

Published: March 19, 2024

Controlling product selectivity in successive reactions of the same type is challenging owing to comparable thermodynamic and kinetic properties involved. Here, synergistic interaction two phosphoryl groups bisphosphine dioxides (BPDOs) with a bromo-phosphonium cation was studied experimentally provide practical tool for substrate–catalyst recognition. As eventual result, we have developed phosphonium-catalyzed monoreduction chiral BPDOs access an array synthetically useful monoxides (BPMOs) axial, spiro, planar chirality, which are otherwise synthesize before. The reaction features excellent impressive reactivity. It proceeds under mild conditions, avoiding use superstoichiometric amounts additives metal catalysts simplify synthetic procedure. accessibility scalability allowed rapid construction ligand library optimization asymmetric Heck-type cyclization, laying foundation broad range applications BPMOs catalysis.

Language: Английский

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