Photoiniferter Polymerization: Illuminating the History, Ascendency, and Renaissance

Progress in Polymer Science, Год журнала: 2024, Номер 156, С. 101871 - 101871

Опубликована: Авг. 22, 2024

Язык: Английский

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Selective Depolymerization for Sculpting Polymethacrylate Molecular Weight Distributions

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Янв. 29, 2025

Chain-end reactivation of polymethacrylates generated by reversible-deactivation radical polymerization (RDRP) has emerged as a powerful tool for triggering depolymerization at significantly milder temperatures than those traditionally employed. In this study, we demonstrate how the facile poly(butyl methacrylate) (PBMA) can be leveraged to selectively skew molecular weight distribution (MWD) and predictably alter viscoelastic properties blended PBMA mixtures. By mixing polymers with thermally active chain ends different weights inactive ends, MWD blends skewed high or low selective depolymerization. This approach leads counterintuitive principle "destructive strengthening" material. Finally, demonstrate, proof concept, encryption information within polymer mixtures linking Morse code MWDs before after depolymerization, allowing encoding data synthetic macromolecules.

Язык: Английский

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Harnessing Non-Thermal External Stimuli for Polymer Recycling

Macromolecules, Год журнала: 2025, Номер 58(5), С. 2210 - 2223

Опубликована: Фев. 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.

Язык: Английский

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Redox-Selective Macromolecular Electrolysis for Sequential Functionalization and Deconstruction

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Март 3, 2025

This study demonstrates that selective macromolecular electrolysis can be achieved on copolymers containing redox-orthogonal targets by controlling the externally applied voltage. We designed macromolecules phthalimide (E1/2 = -1.8 V vs Ag/AgNO3) and tetrachlorophthalimide -1.3 (meth)acrylates have significantly different reduction potentials such they are separately redox-addressable. The polymer-centered radicals generated decarboxylation either undergo (1) hydrogen atom transfer to form olefinic repeat units or (2) β-scission deconstruct polymer backbone. Our results reveal electrochemical control over postpolymerization modifications, which enables sequential transformations tune glass transition temperature of electrochemically a range -54 125 °C. method was also shown maintain its selectivity in blend provided access (poly(styrene-co-propylene-co-ethylene)) would challenging prepare other ways. These demonstrate potential for material functionalization degradation. approach expands toolbox modification targeted degradation with applications information processing, spatiotemporal patterning, producing materials complex architectures driven external stimuli.

Язык: Английский

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Polystyrene–Br End-Group Modification via Electrolysis: Adjusting Hydrogenation vs Coupling Selectivity

ACS Macro Letters, Год журнала: 2025, Номер unknown

Опубликована: Март 7, 2025

Atom transfer radical polymerization (ATRP) enables the precise synthesis of polymers with well-defined architectures, controlled molecular weights, and low dispersity. However, halogen end-groups inherent to ATRP can pose challenges due their chemical reactivity thermal instability. To address these issues, various strategies, including photochemical methods, have been developed for chain-end modification. This study introduces an electrochemical approach selectively reduce in polymers. Using glassy carbon (GC) silver electrodes, reductive cleavage C-Br bromine-capped polystyrene was investigated. Cyclic voltammetry revealed that polystyrene-bromide undergoes electron accompanied by concerted removal functionality. The Ag electrode facilitated electrocatalysis enhanced activity. Controlled-potential electrolysis demonstrated reaction conditions, particularly choice proton donors, significantly influence product distribution, enabling selective hydrogenation or dimerization chain ends. work advances understanding strategies tailoring polymer end-group

Язык: Английский

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Electrochemical Commodity Polymer Up‐ and Re‐Cycling: Toward Sustainable and Circular Plastic Treatment

Macromolecular Rapid Communications, Год журнала: 2025, Номер unknown

Опубликована: Апрель 18, 2025

Abstract The demand for commodity plastics reaches unprecedented dimensions. In contrast to the well‐developed plethora of methods polymer synthesis, sustainable strategies end‐of‐life management continue be scarce. While mechanical re‐cycling often results in downgraded materials, chemical or up‐cycling offers tremendous potential an efficient and green approach, thereby addressing precarious treatment post‐use within a circular carbon economy. Recently, electrochemistry surfaced as uniquely powerful tool via functionalization degradation obtaining either novel polymers with valorized properties high‐value recycled small molecules, respectively. discussing recent progress that domain, future perspectives electrochemical modifications until January 2025 are outlined herein.

Язык: Английский

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Anodic Commodity Polymer Recycling: The Merger of Iron‐Electrocatalysis with Scalable Hydrogen Evolution Reaction

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(48)

Опубликована: Сен. 10, 2024

Abstract Plastics are omnipresent in our everyday life, and accumulation of post‐consumer plastic waste environment represents a major societal challenge. Hence, methods for recycling high demand future circular economy. Specifically, the degradation polymers towards value‐added small molecules constitutes sustainable strategy carbon Despite recent advances, chemical polymer continues to be largely limited redox agents or low energy efficiency photochemical processes. We herein report powerful iron‐catalyzed molecular weight polystyrenes through electrochemistry efficiently deliver monomeric benzoyl products. The robustness ferraelectrocatalysis was mirrored by various real‐life plastics, also on gram scale. cathodic half reaction represented hydrogen evolution (HER). scalable electro‐polymer could solely fueled solar commercially available panel, indicating an outstanding potential decentralized green

Язык: Английский

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Electrochemical Postpolymerization Modification and Deconstruction of Macromolecules

ACS Macro Letters, Год журнала: 2024, Номер unknown, С. 1345 - 1354

Опубликована: Сен. 25, 2024

Electrolysis is an emerging approach to polymer postpolymerization modification, deconstruction, and depolymerization. Electrochemical reactions are particularly appealing for macromolecular transformations because of their high selectivity, ability be externally monitored, intrinsic scalability. Despite these desirable features the recent resurgent use small-molecule electrochemical reactions, development electrolysis has been limited. Herein, we highlight examples driven by heterogeneous redox chemistry. Throughout our exploration electrolysis, provide perspective on opportunities continued investigation in this nascent field. Specifically, how targeted reaction through deeper mechanistic insight will expand scope materials that can (de)constructed with methods. As developed, expect emerge as a high-functioning complementary tool functionalization deconstruction.

Язык: Английский

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An Expedient Route to Bio‐based Polyacrylate Alternatives with Inherent Degradation Capabilities by Organic Catalysis for Polymerization of Muconate Esters

Angewandte Chemie International Edition, Год журнала: 2024, Номер unknown

Опубликована: Сен. 24, 2024

Abstract The quest for polymers that would be at the same time bio‐based and degradable after usage, in addition to offering chemical post‐modification options, remains a daunting challenge contemporary polymer science. Despite advances chemistry, attempts controlling chain‐growth polymerization of muconate esters remain unexplored. Here we show dialkyl muconates can rapidly polymerized by organocatalyzed group transfer (O‐GTP). O‐GTP is conducted completion room temperature toluene within few minutes, using 1‐ethoxy‐1‐(trimethylsiloxy)‐1,3‐butadiene (ETSB) as initiator 1‐tert‐butyl‐4,4,4‐tris(dimethylamino)‐2,2‐bis[tris(dimethylamino)‐phosphoranylidenamino]‐2 5,4 5 catenadi(phosphazene) (P 4 ‐ t ‐Bu) catalyst. Chain extension experiments synthesis all muconate‐type block copolymers also achieved. Furthermore, polymuconates are amenable facile post‐polymerization modification reactions. This showcased through hydrolysis ester side chains leading well‐defined poly(muconic acid), epoxidation C=C double bonds main chain. Last but not least, these internal alkene groups selectively cleaved ozonolysis, demonstrating upcyclability under oxidative conditions. work demonstrates constitute unique platform polymers, easily modifiable being chemically user friendly experimental

Язык: Английский

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Chemical recycling: comprehensive overview of methods and technologies

International Journal of Sustainable Engineering, Год журнала: 2024, Номер 17(1), С. 124 - 148

Опубликована: Окт. 28, 2024

Plastic pollution has emerged as a global environmental crisis, prompting the search for innovative solutions to manage and repurpose plastic waste sustainably. Chemical recycling garnered attention promising strategy address this challenge by converting discarded plastics into valuable feedstocks products. Drawing upon statistical data thorough review of literature, paper examines diverse methodologies technologies employed in chemical recycling, highlighting key advancements their potential economic impacts. The aim article is provide comprehensive overview various methods plastics. In article, reader offered detailed processing methods, including hydrolysis, glycolysis, enzymatic degradation, acid supercritical fluid depolymerisation, catalytic pyrolysis, fast microwave fluidised bed plasma gasification, steam oxidative hydrothermal liquefaction, biological electrochemical processing. literature cited allows gain an in-depth understanding processes at Technology Readiness Levels (TRL) 4 TRL 9, depending on chosen technology.

Язык: Английский

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