Screening the release of chemicals and microplastic particles from diverse plastic consumer products into water under accelerated UV weathering conditions

Journal of Hazardous Materials, Journal Year: 2024, Volume and Issue: 477, P. 135256 - 135256

Published: July 19, 2024

Photodegradation of plastic consumer products is known to accelerate weathering and facilitate the release chemicals particles into aquatic environment. However, these processes are complex. In our presented pilot study, eight were leached in distilled water under strong ultraviolet (UV) light simulating months Central European climate compared their respective dark controls (DCs). The leachates formed exploratorily characterized using a range chemical analytical tools describe degradation leaching processes. These techniques covered (a) microplastic analysis, showing substantial liberation further increased UV exposure, (b) non-targeted mass spectrometric characterization leachates, revealing several hundreds features with typically only minor agreement between exposure corresponding DCs, (c) target analysis 71 organic analytes, which 15 could be detected at least one sample, (d) metal(loid) revealed toxic metal(loid)s enhanced exposure. A data comparison US-EPA's ToxVal ToxCast databases showed that metals additives might pose health environmental concerns, requiring study comprehensive impact assessments.

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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Advance on nickel‐ and palladium‐catalyzed insertion copolymerization of ethylene and acrylate monomers

Journal of Polymer Science, Journal Year: 2023, Volume and Issue: 61(23), P. 2987 - 3021

Published: Aug. 8, 2023

Abstract Nickel‐ and palladium‐catalyzed insertion copolymerization of ethylene acrylate comonomers for synthesis ethylene‐acrylates copolymers have attracted much academic industrial interests remained highly challenging. This review provides an overview the developments in nickel‐ comonomers. Mechanistic interpretation metal‐catalyzed is described. Late transition metal catalysts are divided to nickel‐based palladium‐based with different chelate ligands. The effects catalyst structure on performance copolymer microstructure comprehensively discussed. aims promote design development nickel palladium ethylene/acrylate copolymerizations copolymers.

Language: Английский

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Phosphine–Imidate-Supported Nickel Catalysts for Ethylene/Acrylate Copolymerization

Organometallics, Journal Year: 2024, Volume and Issue: 43(8), P. 859 - 865

Published: April 2, 2024

Phosphine–imidate-supported nickel catalysts were synthesized and tested for ethylene/acrylate copolymerization activity. Phosphine–amide metalation studies with (pyridine)2Ni(CH2Si(CH3)3)2 (py2Ni(CH2TMS)2) suggest that the proceeds via an intermediate phosphine–amide complex ([P,O–amide]Ni(CH2TMS)2). Subsequent deprotonation of amide N–H gives access to phosphine–imidate-supported ([P,O–imidate]pyNi(CH2TMS)). The imidate form ligand proved be critical polymerization phosphine–imidate described herein capable producing copolymers molecular weights (Mw) from 700 120,000 g/mol acrylate incorporation >2.6 mol % in some cases. It was determined hemilabile alkoxy groups on phosphine aryl necessary achieve high Mw incorporation. These results demonstrate phosphine–amides, a well-studied class, can utilized highly active neutral catalysts.

Language: Английский

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Pyridine vs. Thiazole in Cyclometalated N^C^N Ni(II) Complexes

Inorganics, Journal Year: 2025, Volume and Issue: 13(2), P. 41 - 41

Published: Feb. 1, 2025

Six N^C^N cyclometalated Ni(II) complexes [Ni(N^C^N)Cl] or [Ni(N^C^N’)Br] with symmetric non-symmetric N^C^N’ ligands in which the peripheral N-groups were varied pyridine (Py), 4-thiazole (4Tz), 2-thiazole (2Tz), and 2-benzothiazole (2Btz) complementing previously reported di(2-pyridyl)phenide [Ni(Py(Ph)Py)X] X = Cl Br. The synthesized from NiBr2 N^CH^N’ protoligands through base-assisted nickelation, while received N^C(Cl)^N [Ni(COD)2] (COD 1,5-cyclooctadiene). Introduction of 4Tz on both sides shifted electrochemical gap ΔEexp Eox–Ered long wavelength UV-vis absorption maxima to higher energies, 2Tz leads a shift lower energies. When introducing only one as groups, remaining PhPy moiety dominates electronic properties electrochemistry photophysics are very similar Py(Ph)Py derivatives. In contrast this, introduction 2Btz shifts values regardless two groups character frontier molecular orbitals complexes, DFT calculations show. Long-wavelength absorptions vary 416 443 nm, their energies correlate well first reduction potentials. Negishi-type C–C cross-coupling reactions gave total yields ranging 1 60% 44%. reactivities roughly Facilitated (E around –2 higher) goes generally along improved performance, making thiazole-containing interesting candidates for such catalysis.

Language: Английский

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Solvent influence on the mechanism of a mechanochemical metal-halide metathesis reaction

RSC Mechanochemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Subtle differences in how pyridine is introduced can direct mechanochemical reactivity by enabling bond activation and favoring one reaction pathway over another.

Language: Английский

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Ni (II) complexes stabilized by tripodal pyrazole-containing ligands with additional donor atoms in the catalysis of the ethylene oligomerization

Molecular Catalysis, Journal Year: 2025, Volume and Issue: 580, P. 115082 - 115082

Published: April 10, 2025

Language: Английский

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Groups 3 and 4 single-site catalysts for olefin-polar monomer copolymerization

Chinese Chemical Letters, Journal Year: 2025, Volume and Issue: unknown, P. 111297 - 111297

Published: May 1, 2025

Language: Английский

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Tunable Late-Transition-Metal-Catalyzed Polymerization for Controlled Polymer Synthesis

Catalysts, Journal Year: 2023, Volume and Issue: 13(4), P. 670 - 670

Published: March 29, 2023

As a powerful protocol for the preparation of common polymers, such as polyolefins, polyesters, and polycarbonates, late-transition-metal-catalyzed polymerization can be carried out by controlling reaction conditions or developing dynamic catalytic systems that use external stimuli to influence performance active sites, resulting in well-defined polymeric materials. In particularly, under latter conditions, ‘one catalyst’ provide more than one kind polymer with controlled sequence from monomer mixture, making full prepared catalyst. this review, tunable modes, including redox, light electrochemical properties, Lewis acids, alkali metal cations, late-transition-metal-complex (especially iron, cobalt, nickel)-catalyzed were collected thoroughly discussed.

Language: Английский

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A salicylaldiminate/Pd(trifluoroacetate)₂ [SalAld/Pd(tfa)₂] initiating system for C1 polymerization of diazoacetate: generation of an active initiator from ordinary reagents with facile procedures

Polymer Chemistry, Journal Year: 2024, Volume and Issue: 15(11), P. 1077 - 1084

Published: Jan. 1, 2024

SalAld/Pd(tfa) 2 initiating systems have been revealed to be effective for C1 polymerization of diazoacetate, yielding moderately syndiotactic polymers with high M n in moderate yield.

Language: Английский

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