Multifunctional Catalysts for Ring-Opening Copolymerizations

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(18), P. 11037 - 11070

Published: Aug. 26, 2022

The ring-opening copolymerization (ROCOP) of epoxides with CO2 or cyclic anhydrides is a versatile route toward synthesizing wide range polycarbonate and polyester copolymers. ROCOP most commonly uses binary catalyst systems comprising separate Lewis acid nucleophilic cocatalyst components. However, the dependence on two discrete components leads to low activities at loadings, are prone numerous side reactions. It was therefore proposed that covalently tethering together would increase both activity selectivity in epoxide ROCOP. Since these initial efforts, many multifunctional catalysts featuring tethered cationic base cocatalyst(s) have been developed for This review examines CO2, anhydrides, carbonyl sulfide (COS), thioanhydrides. In particular, we will assess how catalysts' mechanisms operations lead improved

Language: Английский

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Progress in the catalytic reactions of CO₂ and epoxides to selectively provide cyclic or polymeric carbonates

Green Chemistry, Journal Year: 2022, Volume and Issue: 24(13), P. 5007 - 5034

Published: Jan. 1, 2022

Sustainability requires that we reuse spent carbon sources from CO2 emissions to generate new products and materials. In this regard, capture is a necessary requirement for avoiding disastrous climate changes. Hence, accompanying technology the need developing low-energy processes dioxide utilization. The coupling of three-membered cycle ethers, aka oxiranes or epoxides, with provide useful cyclic carbonates polymeric materials represents viable approach aid in addressing issue. This results recalcitrant nature being overcome by energy released during epoxide ring opening process, ∼114 kJ mol−1. Noteworthy, instance does not undergo reduction. Consideration origin also importance as epoxides derived renewable resources can be beneficial sustainable process. Consistent concept Green, it value catalysis employed these transformations biocompatible, especially production used biomedical science. review wish present recent developments catalytic chemistry afford either carbonates. Focus will centered on metal catalysis, sequential addition mixtures monomers, use organocatalysts carrying out chemical conversions.

Language: Английский

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Alkyl borane-mediated metal-free ring-opening (co)polymerizations of oxygenated monomers

Progress in Polymer Science, Journal Year: 2022, Volume and Issue: 136, P. 101644 - 101644

Published: Dec. 30, 2022

Language: Английский

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Current Challenges and Perspectives in CO₂-Based Polymers

Macromolecules, Journal Year: 2023, Volume and Issue: 56(5), P. 1759 - 1777

Published: Feb. 28, 2023

Carbon dioxide (CO2) is considered a renewable one-carbon building block for chemical synthesis owing to its abundance, low toxicity, nonflammability, and availability. The incorporation of CO2 into the polymer backbone affords various ester- or carbonyl-containing moieties, which create desired material properties impart unique degradability after use under microbial conditions. In this Perspective, we focus on critical advances in CO2-derived polymers highlight catalytic strategies, novel conceptual routes, potential application fields. outlook perspective are provided describe future challenges new strategies establishing CO2-based with performances economic competitiveness comparable that petroleum-based materials.

Language: Английский

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Copolymerization Involving Sulfur-Containing Monomers

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(24), P. 14038 - 14083

Published: Nov. 2, 2023

Incorporating sulfur (S) atoms into polymer main chains endows these materials with many attractive features, including a high refractive index, mechanical properties, electrochemical and adhesive ability to heavy metal ions. The copolymerization involving S-containing monomers constitutes facile method for effectively constructing polymers diverse structures, readily tunable sequences, topological structures. In this review, we describe the recent advances in synthesis of via or multicomponent polymerization techniques concerning variety monomers, such as dithiols, carbon disulfide, carbonyl sulfide, cyclic thioanhydrides, episulfides elemental (S8). Particularly, significant focus is paid precise control main-chain sequence, stereochemistry, structure achieving high-value applications.

Language: Английский

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Organoboron-mediated polymerizations

Chemical Society Reviews, Journal Year: 2024, Volume and Issue: 53(7), P. 3384 - 3456

Published: Jan. 1, 2024

The scientific community has witnessed extensive developments and applications of organoboron compounds as synthetic elements metal-free catalysts for the construction small molecules, macromolecules, functional materials over last two decades. This review highlights achievements organoboron-mediated polymerizations in past several decades alongside mechanisms underlying these transformations from standpoint polymerization mode. Emphasis is placed on free radical polymerization, Lewis pair ionic (cationic anionic) polyhomologation. Herein, alkylborane/O

Language: Английский

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Efficient and Selective Chemical Recycling of CO₂‐Based Alicyclic Polycarbonates via Catalytic Pyrolysis

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(34)

Published: June 30, 2022

Chemical recycling of polymers to their constituent monomers is the foremost challenge in building a sustainable circular plastics economy. Here, we report strategy for highly efficient depolymerization various CO2 -based alicyclic polycarbonates epoxide solvent-free conditions by simple CrIII -Salen complex mediated catalytic pyrolysis process. The chemical widely studied poly(cyclohexene carbonate) exhibits excellent reactivity (TOF up 3000 h-1 , 0.1 mol % catalyst loading) and high monomer selectivity (>99 %). Mechanistic investigation reveals that process proceeds sequential fashion via trans-carbonate intermediate.

Language: Английский

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Chemical recycling to monomers: Industrial Bisphenol‐A‐Polycarbonates to novel aliphatic polycarbonate materials

Journal of Polymer Science, Journal Year: 2022, Volume and Issue: 60(24), P. 3256 - 3268

Published: April 29, 2022

Abstract The extensive use of commodity polymer materials has led to the depletion natural resources and caused undesirable problem plastic pollution. In this context, design novel polymeric structures with unique recyclability characteristics from renewable recycling real‐life wastes are critical address problems associated increasing demand for plastics. Chemical degradation through polymerization–depolymerization followed by re‐polymerization already emerged as a long‐term strategy toward attainment completely sustainable cycles. Bisphenol‐A‐polycarbonates (BPA–PC) exhibit high thermal resistance, excellent mechanical properties, optical transparency, which make them suitable engineering This review presents our vision realizing circular economy polycarbonate materials—from chemical widely used BPA–PCs aliphatic polycarbonates resources.

Language: Английский

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Key progresses of MOE key laboratory of macromolecular synthesis and functionalization in 2021

Chinese Chemical Letters, Journal Year: 2022, Volume and Issue: 34(5), P. 107592 - 107592

Published: June 12, 2022

Language: Английский

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Precision copolymerization of CO2 and epoxides enabled by organoboron catalysts

Nature Synthesis, Journal Year: 2022, Volume and Issue: 1(11), P. 892 - 901

Published: Aug. 25, 2022

Language: Английский

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