Fast Bulk Depolymerization of Polymethacrylates by ATRP

ACS Macro Letters, Год журнала: 2023, Номер 12(8), С. 1173 - 1178

Опубликована: Авг. 2, 2023

Fast bulk depolymerization of poly(n-butyl methacrylate) and poly(methyl methacrylate), prepared by atom transfer radical polymerization (ATRP), is reported in the temperature range between 150 230 °C. Depolymerization Cl-terminated polymethacrylates was catalyzed a CuCl2/TPMA complex (0.022 or 0.22 equiv vs P-Cl) studied using TGA, also under isothermal conditions. Relatively rapid 5-20 min observed at 180 The preparative scale reactions were carried out short-path distillation setup with up to 84% within 15

Язык: Английский

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Photocatalytic ATRP Depolymerization: Temporal Control at Low ppm of Catalyst Concentration

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(39), С. 21146 - 21151

Опубликована: Сен. 22, 2023

A photocatalytic ATRP depolymerization is introduced that significantly suppresses the reaction temperature from 170 to 100 °C while enabling temporal regulation. In presence of low-toxicity iron-based catalysts and under visible light irradiation, near-quantitative monomer recovery could be achieved (up 90%), albeit with minimal control. By employing ppm concentrations either FeCl2 or FeCl3, during dark periods completely eliminated, thus control possibility modulate rate by simply turning "on" "off". Notably, our approach allowed preservation end-group fidelity throughout reaction, carried out at high polymer loadings 2M), was compatible various polymers sources. This methodology provides a facile, environmentally friendly, temporally regulated route chemically recycle ATRP-synthesized polymers, opening door for further opportunities.

Язык: Английский

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Solvent‐Free Chemical Recycling of Polymethacrylates made by ATRP and RAFT polymerization: High‐Yielding Depolymerization at Low Temperatures

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(38)

Опубликована: Июль 31, 2023

Although controlled radical polymerization is an excellent tool to make precision polymeric materials, reversal of the process retrieve starting monomer far less explored despite significance chemical recycling. Here, we investigate bulk depolymerization RAFT and ATRP-synthesized polymers under identical conditions. RAFT-synthesized undergo a relatively low-temperature solvent-free back thanks partial in situ transformation end-group macromonomer. Instead, can only depolymerize at significantly higher temperatures (>350 °C) through random backbone scission. To aid more complete even lower temperatures, performed facile quantitative modification strategy which both ATRP end-groups were successfully converted macromonomers. The macromonomers triggered temperature with onset 150 °C yielding up 90 % regeneration. versatility methodology was demonstrated by scalable (≈10 g polymer) retrieving 84 intact could be subsequently used for further polymerization. This work presents new low-energy approach depolymerizing creates many future opportunities as high-yielding, methods are sought.

Язык: Английский

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From Plastic Waste to Treasure: Selective Upcycling through Catalytic Technologies

Advanced Energy Materials, Год журнала: 2023, Номер 13(41)

Опубликована: Сен. 24, 2023

The huge amount of plastic wastes has become a pressing global environmental problem, leading to severe pollution and resource depletion through conventional downcycling technologies like incineration landfilling. In contrast, selective upcycling various plastics offers promising solution for converting waste into valuable products. This review provides comprehensive overview the recent advancements in innovative catalytic technologies, including thermocatalysis, electrocatalysis, photocatalysis. Special emphasis is placed on elucidating reaction mechanisms, activating designated chemical bonds high selectivity, elaborating above techniques terms conditions Finally, application prospects future development trends catalysis are discussed, providing insights realizing sustainable circular economy.

Язык: Английский

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Light-driven polymer recycling to monomers and small molecules

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Март 20, 2024

Abstract Only a small proportion of global plastic waste is recycled, which most mechanically recycled into lower quality materials. The alternative, chemical recycling, enables renewed production pristine materials, but generally comes at high energy cost, particularly for processes like pyrolysis. This review focuses on light-driven approaches chemically recycling and upcycling waste, with emphasis reduced consumption selective transformations not achievable heat-driven methods. We focus challenging to recycle backbone structures composed mainly C‒C bonds, lack functional groups i.e., esters or amides, that facilitate e.g., by solvolysis. discuss the use light, either in conjunction heat drive depolymerization monomers via photocatalysis transform polymers valuable molecules. structural prerequisites these are outlined, highlighting their advantages as well limitations. conclude an outlook, addressing key challenges, opportunities, provide guidelines future photocatalyst (PC) development.

Язык: Английский

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Ring-Opening Polymerization of Lactones to Prepare Closed-Loop Recyclable Polyesters

Macromolecules, Год журнала: 2024, Номер 57(5), С. 1919 - 1940

Опубликована: Фев. 22, 2024

The large production and indiscriminate disposal of plastics have resulted in serious resource global environmental crises, which has raised a demand to develop more sustainable circular economy. An ideal strategy address the end-of-life issue is next-generation polymers with closed-loop life cycles, can be selectively depolymerized back monomers at end their service life. Aliphatic polyesters prepared by ring-opening polymerization (ROP) moderately strained lactones shown great potential recyclable polymers. This Perspective highlights recent achievements for that are derived from four-, five-, six-, seven-membered focusing on discussion thermodynamic kinetic considerations, monomer design principles polymer preparations, material properties, chemical recyclability. Finally, current challenges possible directions also discussed.

Язык: Английский

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Photocatalytic Upcycling and Depolymerization of Vinyl Polymers

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(19)

Опубликована: Март 11, 2024

Abstract Photocatalytic upcycling and depolymerization of vinyl polymers have emerged as promising strategies to combat plastic pollution promote a circular economy. This mini review critically summarizes current developments in the degradation including polystyrene poly(meth)acrylates. Of these material classes, polymethacrylates possess unique possibility undergo photocatalytic back monomer under thermodynamically favourable conditions, thus presenting significant advantages over traditional thermal strategies. Our perspective on formidable challenges potential future directions are also discussed.

Язык: Английский

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Recent advances in oxidative degradation of plastics

Chemical Society Reviews, Год журнала: 2024, Номер 53(14), С. 7309 - 7327

Опубликована: Янв. 1, 2024

Oxidative degradation is a powerful method to degrade plastics into oligomers and small oxidized products. While thermal energy has been conventionally employed as an external stimulus, recent advances in photochemistry have enabled photocatalytic oxidative of polymers under mild conditions. This tutorial review presents overview degradation, from its earliest examples emerging strategies. briefly discusses the motivation development with focus on underlying mechanisms. Then, we will examine modern studies primarily relevant catalytic degradation. Lastly, highlight some unique using unconventional approaches for polymer such electrochemistry.

Язык: Английский

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Current status and outlook for ATRP

European Polymer Journal, Год журнала: 2024, Номер 211, С. 113001 - 113001

Опубликована: Март 30, 2024

Atom transfer radical polymerization (ATRP) is one of the most often used controlled techniques. It employs very small amounts (ppm) Cu complexes in presence various chemical reducing agents but also external stimuli such as light, electrical current or mechanical forces. can be carried out bulk, solution, and dispersed media. ATRP has been successfully to prepare polymers with architecture well-defined topology, composition, functionality, well bioconjugates organic–inorganic hybrids. This article summarizes status an outlook for ATRP.

Язык: Английский

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Deconstruction of Polymers through Olefin Metathesis

Chemical Reviews, Год журнала: 2024, Номер 124(11), С. 7007 - 7044

Опубликована: Май 24, 2024

The consumption of synthetic polymers has ballooned; so the amount post-consumer waste generated. current polymer economy, however, is largely linear with most being either landfilled or incinerated. lack recycling, together sizable carbon footprint industry, led to major negative environmental impacts. Over past few years, chemical recycling technologies have gained significant traction as a possible technological route tackle these challenges. In this regard, olefin metathesis, its versatility and ease operation, emerged an attractive tool. Here, we discuss developments in olefin-metathesis-based technologies, including development new materials application metathesis commercial materials. We delve into structure–reactivity relationships context polymerization–depolymerization behavior, how experimental conditions influence deconstruction outcomes, reaction pathways underlying approaches. also look at hurdles adopting relevant future directions for field.

Язык: Английский

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