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 "title": "Living polymerization",
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 "excerpt": "Living polymerization is a chain-growth polymerization in which chain transfer and termination are absent, so growing chains stay active, coined by Michael Szwarc in 1956.",
 "snippet": "Living polymerization is a chain-growth polymerization in which chain transfer and termination are absent, so growing chains stay active, coined by Michael Szwarc in 1956.",
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 "markdown": "# Living polymerization\n\nLiving polymerization is a chain-growth polymerization in which chain transfer and chain termination are absent, so that growing chains remain active and resume growth whenever more monomer is added.<sup>[1](https://goldbook.iupac.org/terms/view/L03597)</sup> Because initiation is typically fast compared with propagation, the number of kinetic-chain carriers stays essentially constant, letting the chemist predetermine molecular weight, obtain narrow dispersity (breadth of the molecular-weight distribution of polymer chains), and assemble block, star, graft, and other architectures by sequential monomer addition.<sup>[1](https://goldbook.iupac.org/terms/view/L03597)</sup><sup> • </sup><sup>[2](https://www.sciencedirect.com/science/article/pii/S1369702105007455)</sup><sup> • </sup><sup>[3](https://pubs.rsc.org/en/content/articlelanding/2023/py/d3py00997a)</sup>\n\n| Key fact | Detail |\n|---|---|\n| Definition | Chain polymerization with no chain transfer or termination; essentially constant kinetic-chain carriers<sup>[1](https://goldbook.iupac.org/terms/view/L03597)</sup> |\n| Chain length | \\( DP_{n} = \\Delta [M]/[I]_{0} \\), monomer consumed per initiator introduced<sup>[2](https://www.sciencedirect.com/science/article/pii/S1369702105007455)</sup> |\n| Dispersity | \\( M_{w}/M_{n} \\le 1.1 \\) for anionic systems; \\( \\le 1.2 \\) or 1.3 for other mechanisms<sup>[4](http://old.polyacs.org/725.html)</sup> |\n| Origin | Term coined in 1956 by Michael Szwarc, in Nature and Journal of the American Chemical Society<sup>[5](https://doi.org/10.1038/1781168a0)</sup><sup> • </sup><sup>[6](https://doi.org/10.1021/ja01592a101)</sup> |\n| Mechanisms | Anionic, cationic, group transfer, ring-opening metathesis, and radical RDRP (NMP, ATRP, RAFT)<sup>[7](https://www.ichp.vot.pl/index.php/p/article/view/2094)</sup> |\n| Architectures | Block, star, brush, gradient, miktoarm star, bottlebrush, end-functional polymers<sup>[3](https://pubs.rsc.org/en/content/articlelanding/2023/py/d3py00997a)</sup><sup> • </sup><sup>[2](https://www.sciencedirect.com/science/article/pii/S1369702105007455)</sup> |\n| Recent capability | Oxygen-tolerant photoATRP in emulsion: \\( Đ \\le 1.20 \\), near-quantitative conversion within 60 min<sup>[8](https://pubs.acs.org/amlccd/article/15/2/316/5074640/Oxygen-Tolerant-Inverse-Microemulsion-and)</sup> |\n\n## How it works\n\nIn a living polymerization every initiator molecule starts one chain, and that chain keeps growing until monomer runs out, because transfer and termination reactions are absent.<sup>[1](https://goldbook.iupac.org/terms/view/L03597)</sup> The number-average degree of polymerization is therefore set by stoichiometry: \\( DP_{n} = \\Delta [M]/[I]_{0} \\), the moles of monomer consumed divided by the moles of initiator introduced.<sup>[2](https://www.sciencedirect.com/science/article/pii/S1369702105007455)</sup> With all chains starting at once and growing at similar rates, the chain-length distribution approaches the Poisson distribution, the narrowest possible for a given \\( DP_{n} \\).<sup>[9](https://nvlpubs.nist.gov/nistpubs/jres/70A/jresv70An5p421_A1b.pdf)</sup>\n\nLivingness is verified kinetically, not by dispersity alone. The experimental criteria are first-order kinetics (\\( \\ln([M]_{0}/[M]) \\) linear in time, indicating a constant active-center concentration), \\( M_{n} \\) linear with monomer conversion, and a narrow molecular weight distribution.<sup>[7](https://www.ichp.vot.pl/index.php/p/article/view/2094)</sup> Szwarc quoted a stricter test of the absence of termination and irreversible transfer: \\( \\ln(1 - P_{n} \\cdot [I]_{0}/[M]_{0}) = -k_{p} \\cdot [I]_{0} \\cdot t \\), whose plot must be linear.<sup>[10](https://pmc.ncbi.nlm.nih.gov/articles/PMC6418526/)</sup> IUPAC permits reversible temporary deactivation of active sites in a living polymerization, provided all macromolecules retain the potential for further growth.<sup>[11](https://kar.kent.ac.uk/97705/1/10.1515_pac-2020-1211.pdf)</sup>\n\nThe strict definition is an ideal rarely met exactly. Szwarc himself added the rider that living polymers \"grow to a desired maximum size while their degree of termination or chain transfer is still negligible\".<sup>[12](http://polymer.chem.cmu.edu/~kmatweb/2000/April_00/JPSPC/terminology.pdf)</sup> IUPAC's anionic entry states that such polymerizations should not be described as living if there is a non-zero probability of termination or irreversible transfer.<sup>[13](https://goldbook.iupac.org/terms/view/08980)</sup>\n\n## How it is done\n\nLiving anionic polymerization is demanding: the carbanionic chain ends are quenched by water, oxygen, and carbon dioxide, so the reaction is run on a high-vacuum line reaching below 5 mTorr, compared with about 50 mTorr for ordinary Schlenk lines.<sup>[14](https://gupolylab.com/wp-content/uploads/2025/06/Lecture-9-to-10-Controlled-Polymerization-I.pdf)</sup> The high-vacuum technique is described as the most reliable route to predictable molecular weight and narrow distributions.<sup>[9](https://nvlpubs.nist.gov/nistpubs/jres/70A/jresv70An5p421_A1b.pdf)</sup> Cationic controlled polymerization is described as much more difficult to carry out than the other controlled/living methods.<sup>[7](https://www.ichp.vot.pl/index.php/p/article/view/2094)</sup> Livingness is demonstrated by adding a second portion of monomer after the first is consumed: in Szwarc's styrene experiment, the viscosity rose and both portions converted quantitatively, proving the chains were still active.<sup>[15](https://pmc.ncbi.nlm.nih.gov/articles/PMC10103213/)</sup>\n\nRadical reversible-deactivation methods are run under ordinary glassware. In ATRP, a transition-metal catalyst reversibly halogenates and dehalogenates dormant chain ends; in RAFT, a thiocarbonylthio transfer agent shuttles radicals between chains; in NMP, a nitroxide caps the chain end reversibly. In each case the same tests apply: first-order kinetics, linear \\( M_{n} \\) versus conversion, and chain extension on adding a second monomer.<sup>[7](https://www.ichp.vot.pl/index.php/p/article/view/2094)</sup>\n\n## Origin\n\nAnionic polymerizations without chain-breaking reactions were described by Ziegler and by Abkin and Medvedev in the 1930s.<sup>[16](http://old.polyacs.org/678.html)</sup><sup> • </sup><sup>[17](https://www.sciencedirect.com/science/article/abs/pii/S0079670007000044)</sup> The reagent that made Szwarc's work possible, sodium naphthalene, was prepared as an addition compound of alkali metals and polycyclic aromatics by Scott, Walker, and Hansley in 1936.<sup>[18](https://doi.org/10.1021/ja01303a022)</sup> Living behavior for ethylene oxide is described as narrow distributions when initiation is comparable to propagation, without using the term living polymerization.\\<sup>[15](https://pmc.ncbi.nlm.nih.gov/articles/PMC10103213/)</sup>\n\nIn 1956 Szwarc and co-workers studied the anionic polymerization of styrene with sodium naphthalene in tetrahydrofuran and coined the term \"living polymers\", initially within quotation marks, which were later dropped.<sup>[15](https://pmc.ncbi.nlm.nih.gov/articles/PMC10103213/)</sup><sup> • </sup><sup>[16](http://old.polyacs.org/678.html)</sup> The concept appeared in two papers that year: a Nature communication titled 'Living' Polymers by M. Szwarc,<sup>[5](https://doi.org/10.1038/1781168a0)</sup> and a [Journal of the American Chemical Society](https://www.edgepedia.org/journal-of-the-american-chemical-society) paper by M. Szwarc, M. Levy, and R. Milkovich on electron-transfer initiation as a new method of forming block polymers.<sup>[6](https://doi.org/10.1021/ja01592a101)</sup> The idea reportedly arose when Samuel Weissman, asked whether electrons had been transferred to styrene, answered \"No use, it polymerizes\"; the persistent red color of the reaction mixture signaled the living anions.<sup>[10](https://pmc.ncbi.nlm.nih.gov/articles/PMC6418526/)</sup> Second-generation controlled/living techniques for other mechanisms followed in the 1980s and 1990s.<sup>[3](https://pubs.rsc.org/en/content/articlelanding/2023/py/d3py00997a)</sup>\n\n## Variants\n\nBeyond anionic chemistry, living or controlled behavior was extended to other mechanisms from the early 1980s.<sup>[16](http://old.polyacs.org/678.html)</sup> Kennedy, Kelen, and Tüdös classified carbocationic systems and introduced the quasiliving concept in 1982.<sup>[19](https://doi.org/10.1080/00222338208077218)</sup> Group transfer polymerization of methacrylates is associated with O. W. Webster and B. C. Anderson.<sup>[20](https://doi.org/10.1007/978-1-4899-2356-1_1)</sup> Living cationic polymerization of isobutyl vinyl ether was achieved with a [hydrogen iodide](https://www.edgepedia.org/hydrogen-iodide)/iodine initiating system.<sup>[21](https://doi.org/10.1021/ma00133a001)</sup> Gilliom and Grubbs showed living ring-opening metathesis polymerization of norbornene via titanacyclobutanes in 1986.<sup>[22](https://doi.org/10.1021/ja00264a027)</sup>\n\nRadical variants transformed the field's reach. Georges, Veregin, Kazmaier, and Hamer reported narrow molecular weight resins by a free-radical (nitroxide-mediated) process in 1993.<sup>[23](https://doi.org/10.1021/ma00063a054)</sup> ATRP was reported in 1995 by Kato, Kamigaito, Sawamoto, and Higashimura with a ruthenium catalyst,<sup>[24](https://doi.org/10.1021/ma00109a056)</sup> and Patten, Xia, Abernathy, and Matyjaszewski obtained very low polydispersities from ATRP in Science in 1996.<sup>[25](https://doi.org/10.1126/science.272.5263.866)</sup> Chiefari and colleagues introduced the RAFT process in 1998.<sup>[26](https://doi.org/10.1021/ma9804951)</sup> Fischer formalized the persistent radical effect that underpins nitroxide and ATRP control.<sup>[27](https://doi.org/10.1021/cr990124y)</sup>\n\nThe three main radical methods differ in mechanism and scope. ATRP uses Ru, Cu, Fe, Ni, and other transition-metal complexes and tolerates monomers from styrenes and (meth)acrylates to acrylonitrile and 4-vinylpyridine; NMP is limited to styrenes, acrylates, and acrylamides and needs high temperatures.<sup>[7](https://www.ichp.vot.pl/index.php/p/article/view/2094)</sup><sup> • </sup><sup>[28](https://www.russchemrev.org/RCR4964pdf)</sup> RAFT operates by degenerative transfer through thiocarbonylthio compounds, in which radicals are neither formed nor destroyed, so an external radical source is required.<sup>[29](https://connectsci.au/ch/article-pdf/58/6/379/1066947/ch05072.pdf)</sup> Later ATRP variants reduced catalyst load and added external control: ARGET ATRP by Jakubowski and Matyjaszewski in 2006,<sup>[30](https://doi.org/10.1002/anie.200600272)</sup> electrochemically mediated ATRP by Magenau, Strandwitz, Gennaro, and Matyjaszewski in 2011,<sup>[31](https://doi.org/10.1126/science.1202357)</sup> and metal-free ATRP with a phenothiazine photocatalyst by Treat and colleagues in 2014.<sup>[32](https://doi.org/10.1021/ja510389m)</sup>\n\n## Applications\n\nThe defining capability is architecture. Sequential monomer addition gives block copolymers, including block copolymers of about \\( 2 \\times 10^{6} \\) g mol⁻¹ by anionic chemistry;<sup>[15](https://pmc.ncbi.nlm.nih.gov/articles/PMC10103213/)</sup> controlled/living techniques generally provide block, bottlebrush, hyperbranched, and miktoarm star copolymers with precise molecular weight and low dispersity.<sup>[3](https://pubs.rsc.org/en/content/articlelanding/2023/py/d3py00997a)</sup> Gradient copolymers of predefined composition profile were made by ATRP copolymerization by Matyjaszewski, Ziegler, Arehart, Greszta, and Pakula in 2000.<sup>[33](https://doi.org/10.1002/1099-1395%28200012%2913:12<775::aid-poc314>3.0.co;2-d)</sup> ATRP products include block and star copolymers, bioconjugates, nanoparticles, and polymer brushes.<sup>[34](https://www.nature.com/articles/s43586-024-00370-y)</sup> Industrially, PPG reported that ATRP materials give molecular weight control, narrow distribution, and block, gradient, comb, and star architectures for coatings,<sup>[2](https://www.sciencedirect.com/science/article/pii/S1369702105007455)</sup> and seeded RAFT emulsion polymerization exploits compartmentalization to make multiblock copolymer latexes at near-complete conversion without purifying intermediate blocks.<sup>[35](https://www.degruyterbrill.com/document/doi/10.1515/ci-2024-0203/html)</sup>\n\nRecent work extends these capabilities. Photocontrolled radical polymerization offers mild conditions, fast rates, high end-group fidelity, and spatiotemporal control, enabling ultrahigh-molecular-weight polymers by photoiniferter RAFT, photoinduced electron/energy transfer-RAFT, and photocontrolled ATRP.<sup>[36](https://www.nature.com/articles/s44160-024-00710-6)</sup> In 2025, a dual catalytic system of methylene blue and Cu/TPMA complexes gave the first fully oxygen-tolerant inverse microemulsion and miniemulsion photoATRP without deoxygenation; after a roughly 20 min induction period, conversion was nearly quantitative within 60 min, with \\( Đ \\le 1.20 \\) and chain extension from \\( M_{n} \\) 13,700 to 41,400.<sup>[8](https://pubs.acs.org/amlccd/article/15/2/316/5074640/Oxygen-Tolerant-Inverse-Microemulsion-and)</sup> Ambient-temperature eRAFT with current-controlled initiation produced triblock and tetrablock copolymer latexes with >95% conversion per block and \\( Đ < 1.115 \\).<sup>[35](https://www.degruyterbrill.com/document/doi/10.1515/ci-2024-0203/html)</sup>\n\n## Limitations and alternatives\n\nEach mechanism carries specific failure modes. Living anionic polymerization of styrene and 1,3-dienes is intolerant of proton-donating or electrophilic functional groups such as hydroxy, amino, cyano, and carbonyl, and cationic controlled polymerization of vinyl ethers, isobutene, and styrenes generally requires temperatures of −80 °C to 0 °C, high-purity reagents, and a dry inert atmosphere.<sup>[7](https://www.ichp.vot.pl/index.php/p/article/view/2094)</sup> Even in radical RDRP, termination is never zero: with unfavorable rate-constant ratios, roughly 20% of chains are deactivated at \\( DP_{n} = 200 \\), rising to 50% by transfer and 70% by termination at \\( DP_{n} = 500 \\).<sup>[4](http://old.polyacs.org/725.html)</sup> In photoiniferter-RAFT of methyl acrylate, dead chains increased linearly with time even after monomer depletion, reaching about 17% after 168 hours of continued irradiation.<sup>[37](https://pubs.rsc.org/en/content/articlehtml/2025/py/d5py00151j)</sup> Single-initiation systems are restricted by the monomers they tolerate, motivating combinations of two or more methods.<sup>[3](https://pubs.rsc.org/en/content/articlelanding/2023/py/d3py00997a)</sup>\n\nAgainst conventional free-radical polymerization, where individual chains grow for only 5–10 s before terminating and \\( M_{w}/M_{n} > 1.5 \\) (typically \\( > 2 \\)),<sup>[29](https://connectsci.au/ch/article-pdf/58/6/379/1066947/ch05072.pdf)</sup><sup> • </sup><sup>[28](https://www.russchemrev.org/RCR4964pdf)</sup> living methods provide control of molecular weight, narrow dispersity, end-group fidelity, and the ability to chain extend.<sup>[12](http://polymer.chem.cmu.edu/~kmatweb/2000/April_00/JPSPC/terminology.pdf)</sup> In controlled radical polymerization, terminated chains are only about 1–10% of all chains, the rest remaining dormant and reactivatable.<sup>[2](https://www.sciencedirect.com/science/article/pii/S1369702105007455)</sup>\n\nThe terminology remains disputed. IUPAC classifies ATRP, RAFT, and stable-radical-mediated polymerization as reversible-deactivation radical polymerization rather than living radical polymerization, because chain termination has a non-zero probability.<sup>[11](https://kar.kent.ac.uk/97705/1/10.1515_pac-2020-1211.pdf)</sup><sup> • </sup><sup>[38](https://doi.org/10.1351/pac-rep-08-04-03)</sup> Matyjaszewski has argued that the term living polymerization should be used regardless of process yield and lists NMP, ATRP, and RAFT as living radical polymerizations.<sup>[12](http://polymer.chem.cmu.edu/~kmatweb/2000/April_00/JPSPC/terminology.pdf)</sup> The two positions have not been reconciled.\n\n## References\n\n1. [IUPAC Gold Book – living polymerization (L03597)](https://goldbook.iupac.org/terms/view/L03597)\n2. [Review Feature: Controlled/living radical polymerization (Materials Today)](https://www.sciencedirect.com/science/article/pii/S1369702105007455)\n3. [Combinations (Є) among controlled/living polymerizations... (Polymer Chemistry, 2023, 14, 4783)](https://pubs.rsc.org/en/content/articlelanding/2023/py/d3py00997a)\n4. [POLY - Nomenclature Note 12 (IUPAC/Polymer Division)](http://old.polyacs.org/725.html)\n5. [M. SZWARC (1956). ‘Living’ Polymers. Nature.](https://doi.org/10.1038/1781168a0)\n6. [M. Szwarc, M. Levy, R. Milkovich (1956). POLYMERIZATION INITIATED BY ELECTRON TRANSFER TO MONOMER. A NEW METHOD OF FORMATION OF BLOCK POLYMERS 1. Journal of the American Chemical Society.](https://doi.org/10.1021/ja01592a101)\n7. [Progress in controlled/living polymerization in aqueous media. Part I. Principles and methods (Polimery, 2001)](https://www.ichp.vot.pl/index.php/p/article/view/2094)\n8. [Oxygen-Tolerant Inverse Microemulsion and Miniemulsion PhotoATRP | ACS Macro Letters (2025)](https://pubs.acs.org/amlccd/article/15/2/316/5074640/Oxygen-Tolerant-Inverse-Microemulsion-and)\n9. [Procedures for homogeneous anionic polymerization](https://nvlpubs.nist.gov/nistpubs/jres/70A/jresv70An5p421_A1b.pdf)\n10. [Dormant Polymers and Their Role in Living and Controlled Polymerizations](https://pmc.ncbi.nlm.nih.gov/articles/PMC6418526/)\n11. [IUPAC terminology for chain polymerization (Pure Appl. Chem. 2021, via Kent Academic Repository)](https://kar.kent.ac.uk/97705/1/10.1515_pac-2020-1211.pdf)\n12. [Living Polymerization: Rationale for Uniform Terminology (Matyjaszewski, J. Polym. Sci. A: Polym. Chem. 38, 1706–1708, 2000; author-hosted copy)](http://polymer.chem.cmu.edu/~kmatweb/2000/April_00/JPSPC/terminology.pdf)\n13. [IUPAC Gold Book – living anionic polymerization (08980)](https://goldbook.iupac.org/terms/view/08980)\n14. [Controlled (“Living”) Polymerization I (university lecture notes)](https://gupolylab.com/wp-content/uploads/2025/06/Lecture-9-to-10-Controlled-Polymerization-I.pdf)\n15. [Quo Vadis Carbanionic Polymerization?](https://pmc.ncbi.nlm.nih.gov/articles/PMC10103213/)\n16. [POLY - Nomenclature Note 19](http://old.polyacs.org/678.html)\n17. [Anionic vinyl polymerization, 50 years after Michael Szwarc](https://www.sciencedirect.com/science/article/abs/pii/S0079670007000044)\n18. [N. D. Scott, J. F. Walker, V. L. Hansley (1936). Sodium Naphthalene. I. A New Method for the Preparation of Addition Compounds of Alkali Metals and Polycyclic Aromatic Hydrocarbons. Journal of the American Chemical Society.](https://doi.org/10.1021/ja01303a022)\n19. [Joseph P. Kennedy, Tibor Kelen, Ferenc Tüdös (1982). Quasiliving Carbocationic Polymerization. I. Classification of Living Polymerizations in Carbocationic Systems. Journal of Macromolecular Science Part A - Chemistry.](https://doi.org/10.1080/00222338208077218)\n20. [O. W. Webster, B. C. Anderson (1992). Group Transfer Polymerization. .](https://doi.org/10.1007/978-1-4899-2356-1_1)\n21. [Masaaki Miyamoto, Mitsuo Sawamoto, Toshinobu Higashimura (1984). Living polymerization of isobutyl vinyl ether with hydrogen iodide/iodine initiating system. Macromolecules.](https://doi.org/10.1021/ma00133a001)\n22. [Laura R. Gilliom, Robert H. Grubbs (1986). Titanacyclobutanes derived from strained, cyclic olefins: the living polymerization of norbornene. Journal of the American Chemical Society.](https://doi.org/10.1021/ja00264a027)\n23. [Michael K. Georges and colleagues (1993). Narrow molecular weight resins by a free-radical polymerization process. Macromolecules.](https://doi.org/10.1021/ma00063a054)\n24. [Mitsuru Kato and colleagues (1995). Polymerization of Methyl Methacrylate with the Carbon Tetrachloride/Dichlorotris- (triphenylphosphine)ruthenium(II)/Methylaluminum Bis(2,6-di-tert-butylphenoxide) Initiating System: Possibility of Living Radical Polymerization. Macromolecules.](https://doi.org/10.1021/ma00109a056)\n25. [Timothy E. Patten and colleagues (1996). Polymers with Very Low Polydispersities from Atom Transfer Radical Polymerization. Science.](https://doi.org/10.1126/science.272.5263.866)\n26. [John Chiefari and colleagues (1998). Living Free-Radical Polymerization by Reversible Addition−Fragmentation Chain Transfer: The RAFT Process. Macromolecules.](https://doi.org/10.1021/ma9804951)\n27. [Hanns Fischer (2001). The Persistent Radical Effect: A Principle for Selective Radical Reactions and Living Radical Polymerizations. Chemical Reviews.](https://doi.org/10.1021/cr990124y)\n28. [Modern trends in controlled synthesis of functional polymers (Russian Chemical Reviews)](https://www.russchemrev.org/RCR4964pdf)\n29. [Living Radical Polymerization by the RAFT Process (Australian Journal of Chemistry, CSIRO)](https://connectsci.au/ch/article-pdf/58/6/379/1066947/ch05072.pdf)\n30. [Wojciech Jakubowski, Krzysztof Matyjaszewski (2006). Activators Regenerated by Electron Transfer for Atom‐Transfer Radical Polymerization of (Meth)acrylates and Related Block Copolymers. Angewandte Chemie International Edition.](https://doi.org/10.1002/anie.200600272)\n31. [Andrew J. D. Magenau and colleagues (2011). Electrochemically Mediated Atom Transfer Radical Polymerization. Science.](https://doi.org/10.1126/science.1202357)\n32. [Nicolas J. Treat and colleagues (2014). Metal-Free Atom Transfer Radical Polymerization. Journal of the American Chemical Society.](https://doi.org/10.1021/ja510389m)\n33. [Gradient copolymers by atom transfer radical copolymerization (Journal of Physical Organic Chemistry, 2000)](https://doi.org/10.1002/1099-1395%28200012%2913:12<775::aid-poc314>3.0.co;2-d)\n34. [Atom transfer radical polymerization | Nature Reviews Methods Primers (2024)](https://www.nature.com/articles/s43586-024-00370-y)\n35. [The renaissance and evolving design of radical polymerization (Graeme Moad, Chemistry International, 2024)](https://www.degruyterbrill.com/document/doi/10.1515/ci-2024-0203/html)\n36. [Photocontrolled radical polymerization for the synthesis of ultrahigh-molecular-weight polymers | Nature Synthesis (2024)](https://www.nature.com/articles/s44160-024-00710-6)\n37. [The livingness of poly(methyl acrylate) under visible light photoiniferter-RAFT polymerization mediated by trithiocarbonates (Polymer Chemistry, 2025)](https://pubs.rsc.org/en/content/articlehtml/2025/py/d5py00151j)\n38. [Aubrey D. Jenkins, Richard G. Jones, Graeme Moad (2009). Terminology for reversible-deactivation radical polymerization previously called \"controlled\" radical or \"living\" radical polymerization (IUPAC Recommendations 2010). Pure and Applied Chemistry.](https://doi.org/10.1351/pac-rep-08-04-03)\n\n---\n*Topic: Encyclopedia › Physical world and mathematics › Chemistry › Chemical principles and methods › Chemical synthesis › Polymer synthesis*\n\n*Initially written Sep 29, 2026 · Reviewed: Sep 30, 2026 · Edited: Sep 30, 2026 · Last review: Sep 30, 2026*\n\n*Copyright 2026 EdgeChat AI, a subsidiary of Biostate AI.*\n\nLicense: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license\n",
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 "credit": "\"Living polymerization\", Edgepedia (EdgeChat), https://www.edgepedia.org/living-polymerization. Edgepedia Community License 1.0.",
 "credit_md": "\"[Living polymerization](https://www.edgepedia.org/living-polymerization)\", Edgepedia (EdgeChat), [https://www.edgepedia.org/living-polymerization](https://www.edgepedia.org/living-polymerization). [Edgepedia Community License 1.0](https://www.edgepedia.org/edgepedia/license).",
 "credit_html": "\"<a href=\"https://www.edgepedia.org/living-polymerization\">Living polymerization</a>\", Edgepedia (EdgeChat), <a href=\"https://www.edgepedia.org/living-polymerization\">https://www.edgepedia.org/living-polymerization</a>. <a href=\"https://www.edgepedia.org/edgepedia/license\">Edgepedia Community License 1.0</a>.",
 "speakable": "Living polymerization is a chain-growth polymerization in which chain transfer and termination are absent, so growing chains stay active, coined by Michael Szwarc in 1956."
}
