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This study demonstrates the superiority of a stable and well-defined heterogeneous cobalt hexacyanocobaltate (Co 3 [Co(CN) 6 ] 2 ), a typical cobalt Prussian Blue Analogue (CoCo-PBA) that catalyzes the copolymerization of carbonyl sulfide (COS) and propylene oxide (PO) to produce poly(propylene monothiocarbonate)s (PPMTC). The number-average molecular weights of the PPMTC were 66.4 to 139.4 kg/mol, with a polydispersity of 2.0-3.9. The catalyst productivity reached 1040 g polymer/g catalyst (12.0 h). The oxygen-sulfur exchange reaction (O/S ER), which would generate random thiocarbonate and carbonate units, was effectively suppressed, and thus the selectivity of the monothiocarbonate over carbonate linkages was up to >99%. It was shown that no cyclic thiocarbonate byproduct was produced during the heterogeneous catalysis of COS/PO copolymerization using CoCo-PBA as the catalyst. The content of monothiocarbonate and ether units in the copolymer chain could be regulated by tuning the feeding amount of COS., (© 2022 Wiley-VCH GmbH.)

Using carbon disulfide (CS2) and carbonyl sulfide (COS) as sulfur‐containing and one‐carbon feedstocks to make value‐added products is paramount for both pure and applied chemistry and environmental science. One of the practical strategies is to copolymerize these bulk chemicals with epoxides to produce sulfur‐containing polymers. This approach contributes to improving the sustainability of polymer manufacturing, provides highly desired functional polymer materials, and has attracted much attention. However, these copolymerizations invariably exhibit the intensely complicated chemistry of O/S exchange reaction, leading to sulfur‐containing polymers with diverse architectures. As the understanding of O/S exchange continues to deepen, recent efforts have guided significant advances in the synthesis of CS2‐ and COS‐based polymers. This review examines the O/S exchange chemistry and summarizes the recent progress in this field to promote the further advance of synthesizing sulfur‐containing polymers from CS2 and COS. [ABSTRACT FROM AUTHOR]

The direct utilization of H2S in polymerization is rarely reported. Here step polymerization of H2S and diacrylates using commercially available organic bases as the catalysts is reported. Poly(thioether‐ester)s are successfully synthesized in an atom‐economical way, as confirmed by 1H NMR spectra, and the molecular weights of these poly(thioether‐ester)s can be up to 64.7 kDa as determined by the gel permeation chromatography, which also shows the polymerization of H2S with diacrylates is stepwise manner. The calculation results show that H2S is first deprotonated by organic base, and the generated HS‐ attacks the double bond of diacrylates through anionic Michael addition, to form the intermediate with double bond and ─SH ends or two ─SH ends (slight excess H2S used). The continuous self‐Michael addition of the polymer species with double bond and ─SH ends is the main manner for chain growth. The resultant polymers exhibit tensile strength and elongation at breaks of as high as 21.6 MPa and 1031%, respectively and can be chemically recycled. This work provides a facile and atom‐economical method to produce sulfur‐containing polymers by directly using commercially available H2S. [ABSTRACT FROM AUTHOR]

Our society has been pursuing high‐performance biodegradable polymers made from facile methods and readily available monomers. Here, we demonstrate a library of enzyme‐degradable polymers with desirable properties from the first reported step polyaddition of diamines, COS, and diacrylates. The polymers contain in‐chain ester and thiourethane groups, which can serve as lipase‐degradation and hydrogen‐bonding physical crosslinking points, respectively, resulting in possible biodegradability as well as upgraded mechanical and thermal properties. Also, the properties of the polymers are scalable due to the versatile method and the wide variety of monomers. We obtain 46 polymers with tunable performance covering high‐Tm crystalline plastics, thermoplastic elastomers, and amorphous plastics by regulating polymer structure. Additionally, the polymerization method is highly efficient, atom‐economical, quantitatively yield, metal‐ and even catalyst‐free. Overall, the polymers are promising green materials given their degradability, simple and modular synthesis, remarkable and tunable properties, and readily available monomers. [ABSTRACT FROM AUTHOR]

Researchers have been chasing plastics that can automatically and fully degrade into valuable products under natural conditions. Here, we develop a series of water‐degradable polymers from the first reported fast and selective cationic copolymerization of formaldehyde (B) with cyclic anhydrides (A). In addition to readily accessible monomers, the method is performed at industrially relevant temperatures (~100 °C), takes tens or even minutes, and uses common acid as the catalyst. Interestingly, such polymers possess tunable AB/ABB‐type repeating units, which are considered to be thermodynamic and kinetic products, respectively, resulting in low carbon content ([O] : [C] up to 1 : 1). Notably, the polymers can completely degrade to valuable diacids within 150 days in water at ambient temperature owing to the incorporation of carboxyl terminals and acid‐responsive acetal units. By washing with aqueous sodium carbonate, the polymers are relatively stable over several months. [ABSTRACT FROM AUTHOR]

The facile synthesis of chemically recyclable polymers derived from sustainable feedstocks presents enormous challenges. Here, we develop a novel, modular, and efficient click reaction for connecting primary, secondary, or tertiary alcohols with activated alkenes via a bridge molecule of carbonyl sulfide (COS). The click reaction is successfully applied to synthesize a series of recyclable polymers by the step polyaddition of diols, diacrylates, and COS. Diols and diacrylates are common chemicals and can be produced from biorenewable sources, and COS is released as the industrial waste. In addition to sustainable monomers, the approach is atom‐economical, wide in scope, metal‐free, and performed under mild conditions, affording unprecedented polymers with nearly quantitative yields. The produced polymers also possess predesigned and widely tunable structure owing to the versatility of our method and the broad variety of monomers. The in‐chain thiocarbonate and ester polar groups can play as breakpoints, allowing these polymers to be easily recycled. Overall, the polymers have broad prospects for green materials given their facile synthesis, readily available feedstocks, desirable performance, and chemical recyclability. [ABSTRACT FROM AUTHOR]

The green revolution in plastics should be accelerated due to growing sustainability concerns. Here, we develop a series of chemically recyclable polymers from the first reported cascade polymerization of H2O, COS, and diacrylates. In addition to abundant feedstocks, the method is efficient and air‐tolerant, uses common organic bases as catalysts, and yields polymers with high molecular weights under mild conditions. Such polymers, structurally like polyethylene with low‐density in‐chain polar groups, manifest impressive toughness and ductility comparable to high‐density polyethylene. The in‐chain ester group acts as a breaking point, enabling these polymers to undergo chemical recycling through two loops. The structures and properties of these polymers also have an immeasurably expanded range owing to the versatility of our method. The readily available raw materials, facile synthesis, and high performance make these polymers promising prospects as sustainable materials in practice. [ABSTRACT FROM AUTHOR]

Preparation of non‐conjugated polymers with long‐wavelength emission and high quantum yield (QY) is still a huge challenge. Herein, we report the first example of linear non‐conjugated polyester exhibiting yellow–green clusteroluminescence (CL) and a high QY of 38 %. We discovered that the polyester P3 with balanced flexibility and rigidity showed the longest CL wavelength and highest QY. Systematically photophysical characterization unravel the key role of ester cluster in the CL and the cluster formation via the aggregate of ester units was visualized. Moreover, P3 was demonstrated to be a highly selective, quick‐responsive (ca. 1.2 min) and sensitive detector (detection limit is 0.78 μM) for irons owing to the fast disassociation of clusters by irons. This work not only gains further mechanistic insight into CL but also provides a new strategy to design high‐efficiency and long‐wavelength CL, meanwhile, enlightens the glorious application prospect of luminescent polyester. [ABSTRACT FROM AUTHOR]

Sensibility to environmental concerns and the actual demand for polymeric materials free of any metal contaminants in most applications have directed research towards significant breakthroughs in organocatalytic polymerizations. The overarching challenge is to develop new and efficient organocatalysts for extending the scope and to improve the performance of organocatalytic polymerizations. Since 2016 commercially available alkyl boranes, especially triethyl borane (TEB), have been discovered as exceptional Lewis acids that served to generate ate complexes by combination with chain ends on the one hand and to activate epoxides on the other. This double role of boranes has received widespread attention especially in oxygenated polymer synthesis. Lewis pairs consisting of alkyl boranes combined with an onium salt or organic base has indeed demonstrated unprecedented versatility for (co)polymerizations of oxygenated monomers such as epoxides, oxetanes, cyclic esters and with CO 2 , COS, isocyanates, or cyclic anhydrides, producing a variety of oxygenated polymers. In this review, we take TEB-mediated polymerization systems as the main line of emerging area, summarize the progress comprehensively made to promote the rapid development of organocatalytic polymerizations of oxygenated polymers by these systems, and propose key challenges in organocatalytic synthesis in the future. [Display omitted] [ABSTRACT FROM AUTHOR]