Copper and ZnO Dual-Catalyzed Photo-Assisted depolymerization of Poly(Methyl Methacrylate) without deoxygenation

European Polymer Journal, Journal Year: 2024, Volume and Issue: 220, P. 113429 - 113429

Published: Sept. 2, 2024

Despite significant advancements in thermal and photothermal depolymerizations, the success of these techniques relies on tedious deoxygenation procedures. Herein, we report development depolymerization technique efficient without prior deoxygenation, which was enabled by copper/ligand complexes inclusion (0.25 wt% relative to solvent) zinc oxide (ZnO) nanocrystals activated UV light. This approach tested for poly(methyl methacrylate) (PMMA) prepared atom transfer radical polymerization (ATRP); effects solvent polarity activity ligands were investigated. Unexpectedly, a low-activity Cu-complex with 2,2'-bipyridyne ligand, combination low-polarity solvent, 1,2,4-trichlorobenzene, relatively high yields less than 1 h at 150 °C. Higher ATRP tris(2-pyridylmethyl)amine (TPMA) N,N,N',N'',N''-pentamethyldiethylenetriamine (PMDETA) ligands, efficient, associated their decomposition and/or excessive formation radicals premature termination chain ends. The presented facile designed be used even partially aerated reactors, opening new avenues depolymerization.

Language: Английский

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Emerging Plastic Recycling Strategies Based on Photothermal Conversion

ACS Applied Polymer Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 3, 2025

Increasing plastic pollution presents a significant challenge for humanity and ecosystems. Photothermal (light-to-heat) conversion has emerged as promising strategy recycling waste. Upon light irradiation, photothermal agents provide intense thermal gradients localized to their surfaces, wherein the heat exceeds degradation temperature (Td) of polymers, inducing efficient depolymerization and/or degradation. Thermoplastics (including polyethylene terephthalate (PET), polypropylene (PP), (PE), polystyrene (PS), polycarbonate (PC)) thermosets (epoxy resin) are subject under mild conditions. This review summarizes some key results advancements in polymer waste mitigation using upcycling.

Language: Английский

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Harnessing Non-Thermal External Stimuli for Polymer Recycling

Macromolecules, Journal Year: 2025, Volume and Issue: 58(5), P. 2210 - 2223

Published: Feb. 18, 2025

Polymeric materials have become indispensable due to their versatility and low cost, yet environmental impact presents a significant global challenge. Traditional chemical recycling methods typically rely on heat as stimulus; for instance, pyrolysis is popular methodology which faces limitations high energy consumption, product selectivity, the generation of undesirable byproducts. In response, recent advances in promotion depolymerization degradation through alternative stimuli such light, electrochemistry, mechanical force, shown promising potential more efficient selective polymer breakdown, yielding either starting monomers or valuable small molecules. This perspective explores key examples these emerging strategies, highlighting improve upon current protocols offer pathways under milder conditions, while identifying challenges that future research must address translate chemistry into viable broadly applicable strategies.

Language: Английский

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Oxygen‐Tolerant ATRP Depolymerization Enabled by an External Radical Source

Macromolecular Rapid Communications, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 22, 2025

Abstract Although the chemical recycling of polymers synthesized by controlled radical polymerization enables recovery pristine monomer at low temperatures, it operates efficiently under strictly anaerobic conditions. Instead, oxygen‐tolerant depolymerizations are scarce, and either restricted to use a boiling co‐solvent or performed in closed vessels, often suffering from conversions. Here, an open‐vessel, depolymerization atom transfer (ATRP)‐synthesized is introduced, leading high percentages regeneration (>90% efficiency). Dissolved oxygen eliminated utilizing catalyst loadings, lower loadings combined with initiator. Notably, methodology compatible various solvents (i.e., anisole, 1,2,4‐trichlorobenzene (TCB), 1,2‐dichlorobenzene (DCB), etc.) range commercially available ligands including tris 2‐(dimethylamino)ethylamine (Me 6 TREN) tris(2‐pyridylmethyl)amine (TPMA), as well more inexpensive alternatives such tris(2‐aminoethyl)amine (TREN) N,N,N‘,N‘‘,N‘‘ ‐pentamethyldiethylenetriamine (PMDETA).

Language: Английский

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Polymer Chain Modification via HAT Chemistry and Its Application in Graft Copolymer Synthesis

ACS Macro Letters, Journal Year: 2025, Volume and Issue: unknown, P. 396 - 404

Published: March 15, 2025

Hydrogen atom transfer (HAT) chemistry has emerged as a powerful tool for selective molecular functionalization, with significant applications in the pharmaceutical and agricultural industries. More recently, HAT been explored polymer versatile strategy introducing targeted functional groups onto chains, enabling precise control over properties such solubility mechanical strength. This study investigates use of to synthesize reversible addition–fragmentation chain (RAFT) agents (or agents, CTAs) by modifying various substrates, including toluene, ethyl acetate, dioxane, presence bis(dodecylsulfanylthiocarbonyl) disulfide or bis(3,5-dimethyl-1H-pyrazol-1-ylthiocarbonyl) disulfide. The resulting CTAs were evaluated both thermal photoinduced electron (PET)-RAFT polymerization controlled monomers. approach was then extended functionalize polycaprolactone (PCL) polyvinyl acetate (PVAc), synthesis graft copolymers vinyl To promote HAT, range photocatalysts, iron(III) chloride (FeCl3), investigated, offering advantages conventional systems. Photocatalysis enables mild efficient radical generation under light irradiation, providing cost-effective environmentally friendly alternative expensive toxic metal catalysts.

Language: Английский

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Bulk depolymerization of PMMA using difunctional pyromellitic or monofunctional phthalimidic ATRP initiators

European Polymer Journal, Journal Year: 2024, Volume and Issue: unknown, P. 113646 - 113646

Published: Dec. 1, 2024

Language: Английский

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3D Printing with Light for Personalized Drug Delivery Systems and Medical Devices

ACS Applied Polymer Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 9, 2024

Language: Английский

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