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A series of bis(oxazoline) rare-earth metal dialkyl complexes [(L)Ln(CH2SiMe3)2(THF)n] (L = L1 (dimethyl-substituted bis(oxazoline) ligand), Ln = Y (1-Y), Lu (1-Lu), Sc (1-Sc), n = 1; L = L2 (phenyl-substituted bis(oxazoline) ligand), Ln = Y (2-Y), Lu (2-Lu), Sc (2-Sc), n = 2) was successfully prepared. NMR spectroscopy and X-ray diffraction indicated that all the complexes ligated with a C2 symmetric bis(oxazoline) and two trimethylsilylmethyl ligands. In the presence of borate and triisobutyl aluminium, these complexes exhibited high catalytic activity for the polymerization of isoprene, yielding the polymer with high cis-1,4-regularity (up to 99.9%) and high molecular weight. Moreover, these ternary catalytic systems also served as efficient initiators for the polymerization of polar ortho-methoxystyrene. However, atactic polymers in all the cases were isolated despite the C2 symmetric geometry of bis(oxazoline) ligands. [ABSTRACT FROM AUTHOR]

The polymerization mechanism of 2-vinylpyridine catalyzed by cationic yttrium complexes with diverse ancillary ligands, specifically [L¹Y(CH2SiMe3)(THF)]+ [L¹ = (2,6-Et2C6H3)NC(Me)CHC(Me)N(2,6-Et2C6H3)] (Y-1), [L²Y(CH2SiMe3)(THF)]+ [L² = (2,6-Cl2C6H3)NC(Me)CHC(Me)N(2,6-Cl2C6H3)] (Y-2), and [L³Y (CH2SiMe3)(THF)]+ [L³ = (2,6-C6H5)NC(Me)CHC(Me)N(2,6-iPr2C6H3)] (Y-3), was studied using density functional theory (DFT) calculations. Having achieved an agreement between theory and experiment, it is found that isotactic selectivity induced by Y-1 or Y-2 results from a combination of smaller deformation of the catalyst and stronger electronic effects. Conversely, the Y-3 complex exhibits comparable energy barriers for proceeding via either isotactic or syndiotactic pathways, aligning with the production of atactic polymers as seen experimentally. To examine the steric effects on the kinetic and thermodynamic properties, a computational model of an analogue complex [L4Y(CH2SiMe3)(THF)]+ [L4 = (2,6-Cl2C6H3)NC (Me)CHC(Me)N(iPr2C6H3)] (Y-4), featuring increased steric hindrance, was analyzed. Distortion-interaction and topographic steric map analyses further affirmed that steric hindrance significantly influences stereoselectivity. A direct relationship was identified between the energy barriers of isotactic insertion transition states and the bulkiness of ancillary ligands; greater distortion energy of the catalyst correlates with higher barriers for isotactic polymerization. These findings enhance the mechanistic comprehension of 2-vinylpyridine polymerization and are expected to contribute valuable insights for the improvement of catalytic polymerization systems of 2-vinylpyridine. [ABSTRACT FROM AUTHOR]

Hydrogel‐based optical waveguides have attracted extensive attention in optogenetics, implantable photomedicine, and biosensors due to their excellent biocompatibility and tissue‐like modulus in compared with traditional SiO2‐based rigid optical fibers. However, the existing ion‐induced supramolecular assembly of alginate‐based hydrogel optical fibers commonly lack of long‐term stability due to poor mechanical property accompanied with swollen. In this paper, a novel catalytic surface polymerization method is developed based on a redox reaction mechanism to in situ grow robust and slippery cladding layer on a core poly(ethylene glycol) dimethacrylate (PEGDA) hydrogel fiber by using the alternative H‐bonding poly(N ‐acryloyl glycinamide) (PNAGA) hydrogels. The resultant hydrogel optical fiber with core‐cladding heterogeneous structure can achieve the desirable total reflection condition, leading to good light transmission and low light loss. The PNAGA cladding with robust H‐bonding network endows the hydrogel optical fiber with high stability and outstanding lubrication in humid environment. More importantly, the hydrogel optical fiber possesses good tissue‐like mechanical performance together with excellent biocompatibility, which shows the great advantages for biomedical applications in compared with traditional glass optical fibers. This work will broaden implantable hydrogel optical fibers in material design and structure processibility, promoting the use of hydrogel‐based optical fibers in various applications. [ABSTRACT FROM AUTHOR]

Bicenter (BCn) cobalt-bis(imine) catalysts were synthesized to be used for the polymerization of methyl methacrylate (MMA) and 1-hexene. The effect of catalyst structure, bridging ligand and polymerization reaction conditions was investigated. Synthesis of primary ligand (2,6-dibenzhydryl-4-ethoxyphenyl)-N=(CH3 )- C(CH3 )=O was also done. Following to that, the final ligands of the BC1 and BC2 bicenter catalysts were prepared via reacting the primary ligand with 2,3,5,6-tetramethylbenzene-1,4-diamine and 4,4-methylenedianiline bridges, respectively. The BC1 catalyst demonstrated higher activity than the BC2 catalyst. The highest activity for the BC1 catalyst was obtained when the co-catalyst to catalyst molar ratio was [Al]/[Co]=1500:1, and the polymerization temperature was 40°C. In comparison, the BC2 catalyst demonstrated the highest activity and higher thermal stability in the conditions of: [Al]/[Co]=500:1 ratio and 70°C polymerization temperature. The ¹H NMR analysis results revealed that the highest branching density for the poly(methyl methacrylate) (PMMA) produced by the BC1 and BC2 catalysts was 222 and 249 branches per 1000 carbon atoms, respectively. The PMMA synthesized with the BC2 catalysts had the highest syndiotacticity (59%). The polymer produced with the bicenter catalyst (BC1) showed a relatively broad molecular weight distribution (2.9), according to the GPC analysis results. The synthesized catalysts demonstrated appropriate activity for the polymerization of MMA, but only moderate activity for 1-hexene monomer. [ABSTRACT FROM AUTHOR]

The information available in daily plant operation data is not fully exploited by polymer reaction engineers: what do the catalytic olefin polymerization plants tell? In this article, a method is proposed to increase catalyst and process know‐how, based on experimentally acquired production rate results, coming from a continuous tandem reactor polymerization process. The polymer reaction engineering methodology is also discussed in detail for connecting the catalyst reaction performance to the expected activity profile and yield for batch operation, together with the residence time distribution effect for continuous operation. The potential of the proposed methodology is highlighted with a theoretical example and the effectiveness of the method is demonstrated with an applied example, accurately estimating deactivation parameter values for two catalysts based on plant information and, validated based on small‐scale polymerization experiments. [ABSTRACT FROM AUTHOR]

Seed emulsion polymerization was an effective modification method to improve not only the properties of polymers but also the compatibility between different polymers by designing special core-shell structures. In this study, poly (butadiene-styrene-vinyl pyridine) (VPR)/poly (acrylonitrile-butadiene) (NBR) core–shell nanoparticles (VPR/NBR) were prepared by seed emulsion polymerization using VPR as seed emulsion and butadiene and acrylonitrile as monomers. Subsequently, HVPR/HNBR was obtained by direct hydrogenation of the core–shell nanoparticles in latex using Wilkinson's catalyst under high temperature and H2 pressure. It is noteworthy that the unsaturated C=C double bonds in the core (VPR) and shell (NBR) of HVPR/HNBR nanoparticles were reduced simultaneously during the hydrogenation process without obvious sequence. The particle size and size distribution of the particles remained consistent before and after hydrogenation, indicating that the synthesized core-shell nanoparticles have excellent stability. This study provides a new perspective on the chemical modification of NBR and promises an environmentally friendly "green" process for the industrial hydrogenation of unsaturated elastomers. [ABSTRACT FROM AUTHOR]

Mesophase pitch is usually prepared by radical polymerization or catalytic polymerization from coal tar, petroleum, and aromatic compounds, and the catalytic synthesis of mesophase pitch from pure aromatic compounds is more controllable in the preparation of high-quality mesophase pitch. However, the corrosive and highly toxic nature of the catalyst has limited the further development of this method. In this study, mesophase pitch was synthetized using ethylene tar and naphthalene as raw materials and boron trifluoride diethyl etherate as a catalyst. The effect of the catalytic reaction on the structure and properties of the mesophase pitch was investigated. The results show that naphthalene plays an important role in the mesophase content and reaction pressure (from above 6 MPa to 2.35 MPa). Mesophase pitch with fine-flow texture can be prepared by introducing more methylene groups, naphthenic structures, and aliphatic hydrocarbons during synthesis. Carbon fibers prepared from mesophase pitch show a split structure, and the thermal conductivity is 730 W/(m·K). This work provides theoretical support for lower toxicity and causticity and for reaction-controlled technology for the synthesis of high-purity mesophase pitch. [ABSTRACT FROM AUTHOR]

The development of catalysts has significantly advanced the progress of polyolefin materials. In particular, group 4 (Ti, Zr, Hf) non-metallocene catalysts ligated with [N,N] bidentate ligand(s) have garnered increasing attention in the field of olefin polymerization due to their structurally stability and exceptional polymerization behaviors. Ligands containing nitrogen donors are diverse and at the core of many highly active catalysts. They mainly include amidine, guanidinato, diamine, and various N-heterocyclic ligands, which can be used to obtain a series of new polyolefin materials, such as ultrahigh molecular weight polyethylene (UHWMPE), olefin copolymers (ethylene/norbornene and ethylene/α-olefin) with high incorporations, and high isotactic or syndiotactic polypropylene after coordination with group 4 metals and activation by cocatalysts. Herein, we focus on the advancements and applications of this field over the past two decades, and introduce the catalyst precursors with [N,N] ligand(s), involving the effects of ligand structure, cocatalyst selection, and polymerization conditions on the catalytic activity and polymer properties. [ABSTRACT FROM AUTHOR]

In the field of polymers and organometallic chemistry, a significant gap is apparent in the area of research on well‐defined metal complexes targeted for using in catalysis leading to olefinic oligomers and polymers. Here, we report on the use in these processes the dipicolinate oxovanadium(IV) complexes, without and with auxiliary ligands, i. e. 1,10‐phenanthroline and 2,2'‐bipyridine. The investigated complexes turned out to be versatile precatalysts. After reaction with appropriate activator, they exhibited 11 times higher a catalytic activity than reference vanadium(IV) complexes with salen ligands – so far, precatalysts from a group of vanadium(IV) complexes with the highest known catalytic activity for polymerization of ethylene. In the case of the oligomerization of polar monomers (2‐chloro‐2‐propen‐1‐ol and 3‐buten‐2‐ol) the complexes described in this report have a catalytic activity (very high) similar to vanadium(IV) complexes known in the literature. [ABSTRACT FROM AUTHOR]

Significant advancements have been made in metallocene catalysis due to the development of cyclopentadienyl (Cp) ligands by numerous researchers. Furthermore, various ligand combinations have been realized in the last 20 years for the development of post‐metallocene catalysts. Although ligands containing a Cp have been widely reported, only a few reports exist ligands based on other carbon‐only π‐electron moieties. Herein, we focused on the zirconium and hafnium with the 10π‐electron cyclooctatetraenyl (Cot) dianion as an ancillary ligand and investigated the olefin‐polymerization ability of these complexes. Thus, we performed ethylene and ethylene‐1‐octene (co)polymerization using dMAO, MMAO, and Ph3C[B(C6F5)4]/iBu3Al as cocatalysts and confirmed that completion of the polymerization reaction; the catalytic system except dMAO exhibited activities for olefin polymerization to give linear polyethylene or ethylene‐1‐octene copolymer. Furthermore, the zirconium complexes bearing trimethylsilyl‐substituted Cot ligand exhibited enhanced activities for ethylene polymerization compared with an unsubstituted CotZr catalyst. [ABSTRACT FROM AUTHOR]

The sustainable solution to the environmental problem of polymeric materials calls for efficient and well‐controlled ring‐opening polymerization catalytic systems. Inspired by the highly reactive and stereospecific bimetallic catalysts, three kinds of bimetallic Salen‐Mn catalysts supported by biaryl linking moieties are synthesized and applied to polymerization catalysis of lactide (LA) and ϵ‐caprolactone (ϵ‐CL) in this work. The polymerization is initiated in situ by the ring‐opening of epoxide compounds, in which the ionic cocatalyst could accelerate the reaction process. The Mn−Mn coordination effect contributes to the higher activity and iso‐selectivity towards LA compared to the mononuclear Salen‐Mn catalyst. The reactivity and stereoselectivity are determined by the conformation of catalysts, specifically the Mn−Mn separation and dihedral angle. Finally, the CO2‐controlled switchable polymerizations are carried out with LA and ϵ‐CL. The reversibility of the on‐off switching operation is influenced by the combination between CO2 molecules and active species. The success in binuclear Salen‐Mn catalysts not only expands the range of bimetallic catalyst analogues but also claims the promising potential of Mn‐based catalysts in practical and theoretical research. [ABSTRACT FROM AUTHOR]

Polymers that can be extracted or manufactured from renewable resources such as sugars, natural acids, or terpenes are increasingly relevant. In this context, biobased lactones are a group of monomers that can be synthesized from renewable feedstocks and combine versatility with the ability to yield high-performing materials including both thermoplastics and thermosets. In this chapter, an overview of different kinds of catalytic ring-opening polymerization (ROP) mechanisms including coordination, organocatalyzed, and enzymatic reactions is discussed. ROP of renewable lactones to yield polyesters are classified by their origin. In particular, we report on recent advances in ROP of terpene-based precursors such as limonene and pinene that lead to a variety of caprolactone derivatives which are available for polymerization. Moreover, lactones that can be converted from sugars and natural acids (e.g., fatty acids, amino acids) will be discussed. [ABSTRACT FROM AUTHOR]

The dimeric amide lanthanum complex {[ CP(O)Ph2]La[N(SiMe3)2](µ2-OP(O)Ph2)}2 (PzlMe2 is 3,5-dimethylpyrazole) bearing the N,N,O-tridentate heteroscorpionate ligand is synthesized. As found by X-ray diffraction (XRD) (CIF file CCDC no. 2212274), the complex is binuclear and its lanthanum ions are linked by two bridging monoanionic diphenyl phosphinate ligands. The synthesized lanthanum complex demonstrates a high catalytic activity in the polymerization with ring opening of rac-lactide and ε-caprolactone providing the quantitative conversion of 500 equivalents of the monomer to the polymer at room temperature within 360–720 min for rac-lactide and 10–30 min for ε-caprolactone. The formed polylactides are characterized by the atactic microstructure (Pr = 0.54–0.56) and polydispersity indices (PDI) of 1.6–2.5, whereas for polycaprolactone PDI = 2.1–2.8. [ABSTRACT FROM AUTHOR]

Despite the Ni(II) α-diimine based ethylene polymerization catalysts were discovered almost 30 years ago, the mechanism of the ethylene polymerization over these catalysts still remains the subject of the numerous investigations. A significant progress in understanding the nature and role of the nickel compounds formed in real catalyst systems was made over the past 5–7 years. In present publication we summarized and analyzed the data on the nature and role of Ni(II) and Ni(I) species in the catalyst process. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Mechanoredox chemistry that uses highly polarized piezoelectric materials as mechanoredox catalysts to promote redox reactions has emerged recently. It provides an alternative approach alongside the existing polymerization methods. Despite recent accomplishments, determining the quantitative relationship between the structure of ZnO and its catalytic performance for polymerization is still challenging. Herein, we prepared various ZnO crystals with different polar facets ratios to achieve efficient mechanically induced reversible addition‐fragmentation chain transfer polymerization (mechano‐RAFT). ZnO prepared from Zn(NO3)2 showed a high polar facet ratio of 1.66 and offered the highest catalytic activity among all ZnO samples. A near‐quantitative initiator efficiency of 99.5% and narrow molecular weight distribution were achieved for the polymerization of n‐butyl acrylate. Furthermore, the high chain‐end fidelity and chain extension capability were also evidenced by MALDI‐TOF MS and GPC analysis. This work highlighted the significant contribution of polar facets in ZnO to its catalytic activity and will guide the design of mechanoredox catalysis with superior catalytic performance in the future. [ABSTRACT FROM AUTHOR]

Industrial and disinfection wastewater typically contains high levels of organic pollutants and residue hydrogen peroxide, which have caused environmental concerns. In this work, dual‐asymmetric MnO2@polymer microreactors are synthesized via pollutant polymerization for self‐driven and controlled H2O2 decomposition. A hollow and asymmetric MnO2 nanotube is derived from MnO2 nanorods by selective acid etching and then coated by a polymeric layer from an aqueous phenolic pollutant via catalytic peroxymonosulfate (PMS)‐induced polymerization. The evolution of particle‐like polymers is controlled by solution pH, molar ratios of PMS/phenol, and reaction duration. The polymer‐covered MnO2 tubing‐structured micromotors presented a controlled motion velocity, due to the reverse torque driven by the O2 bubbles from H2O2 decomposition in the inner tunnels. In addition, the partially coated polymeric layer can regulate the exposure and population of Mn active sites to control the H2O2 decomposition rate, thus avoiding violent motions and massive heat caused by vigorous H2O2 decomposition. The microreactors can maintain the function of mobility in an ultra‐low H2O2 environment (<0.31 wt.%). This work provides a new strategy for the transformation of micropollutants to functional polymer‐based microreactors for safe and controlled hydrogen peroxide decomposition for environmental remediation. [ABSTRACT FROM AUTHOR]

A series of rare-earth metal bis(alkyl) complexes have been prepared via protonolysis reactions of tris(aminobenzyl) complexes (Ln(CH2C6H4N(Me)2-o)3) with phosphine-functionalized amidinated ligands (DippNCN(CH2)nPPh2, n = 2 (L1-H) and n = 3 (L2-H)). The X-ray diffraction of P2-Sc (DippNCN(CH2)3PPh2Sc(CH2C6H4N(Me)2-o)2) showed the un-coordination of the diphenylphosphine group due to the inherent saturation of the central metal ion. In conjunction with [Ph3C][B(C6F5)4], all the rare-earth metal complexes showed a high catalytic activity for the polymerization of 1,3-conjugated dienes (isoprene, β-myrcene and β-farnesene), affording highly 3,4-regular polymers (up to 100% 3,4-) with high molecular weight and narrow molecular weight distribution. After the abstraction of the alkyl moiety –CH2C6H4N(Me)2-o of P1-Sc by [Ph3C][B(C6F5)4], the species with the coordination of the diphenylphosphine group to the central metal probably formed, as shown in the 31P NMR spectra and DFT calculation results, and it might serve as the true active species in the 3,4-selective polymerization of 1,3-conjugated dienes. [ABSTRACT FROM AUTHOR]

A thermodynamic simulation package is developed for the catalytic polymerization of olefins in autoclave slurry, loop slurry, gas‐phase, and autoclave solution reactors. The number of components in the reactors may vary from two to six. The simulator uses the Sanchez–Lacombe theory, one of the major thermodynamic models in the polymer industry. Step‐by‐step instructions on how to specify the system, derive and solve the resulting nonlinear equations, and estimate the required thermodynamic properties are given. The software is used to describe ethylene/1‐hexene copolymerizations with hydrogen in different reactors under industrial conditions. These simulations demonstrate why thermodynamic effects must be included in olefin polymerization models. [ABSTRACT FROM AUTHOR]

Functionalized polyethylene-based nanocomposites were prepared by in situ polymerization of ethylene with modified or neat MCM-41 nanoparticles (NMCM-41). Two different synthetic approaches were investigated to improve the compatibility between the hydrophobic HDPE matrix and the hydrophilic NMCM-41: (i) incorporation of UA into the polymeric matrix by copolymerization with ethylene, promoted by the zirconocene catalyst under homogeneous conditions, in the presence of pristine NMCM-41; (ii) use of undecenoic acid (UA) as an interfacial agent to obtain decorated NMCM-41 to be used as nanofiller for the in situ ethylene polymerization, catalyzed by Cp2ZrCl2/MAO under supported conditions. The strong polar character of the carboxylic group is expected to either increase the hydrophilicity of the HDPE chains (strategy i) or interact with the NMCM-41 surface and provide an additional link to the polymeric chains via copolymerization of the vinyl group under supported conditions (strategy ii). Although metallocene catalysts have been shown to copolymerize olefins with functional monomers, the presence of oxygen-containing compounds in the reaction media strongly affects the polymerization activity as a result of the interaction of functional groups with the electrophilic active center of the catalyst. Thus, UA was pre-contacted with tri(isobutyl)aluminum (TIBA) prior to its use in the polymerization to reduce the deactivating character of the carboxylic acid groups towards the zirconocene catalyst. The influence of the UA presence on the polymerization behavior of the protection step is discussed, and the polymerization activities observed for the different approaches are compared. In addition, the thermal behavior and structural details of the resulting materials have been characterized. The impact of using neat or functionalized NMCM-41 on the final dispersion within the polymeric matrix is also analyzed, which is correlated with the mechanical performance exhibited by these HDPE_UA_NMCM-41 nanocomposites. [ABSTRACT FROM AUTHOR]

The traditional two‐component Ziegler‐Natta catalyst has low catalytic activity when initiating ring‐opening metathesis polymerization (ROMP) and is unstable and easy to generate polymerization gels. Therefore, it is necessary to add a third group of ligands with appropriate steric hindrance to improve the catalytic activity of the catalyst. The effects of ligands′ steric hindrance and other reaction conditions on the catalytic activity of tungsten hexachloride (WCl6) as catalyst and aluminum triethyl (AlEt3) as co‐catalyst were investigated. The results showed that the size of the ligands′ steric hindrance affected the catalytic activity of ROMP, and the small steric hindrance caused the polymerization rate to be too fast, which was easy to produce gels, and when the steric hindrance of the ligands was too large, its solubility was not good, which was not conducive to the normal polymerization. When stearyl alcohol was selected as the ligand, the highest catalytic activity was 3123 mol cycloolefin polymer (COP)/mol W, and the reaction speed of polymerization was also the fastest and the complete transformation only needed 30 min when the ligand/W was 25. It was found that the polymerization reaction was stable without gels and the obtained polymer molecular weight was appropriate, 17.8 kDa, under the conditions of Al/W=80, reaction temperature 60 °C, monomer concentration 10 w/v %, catalyst/monomer 5*10−4 : 1, chain transfer agent/monomer 0.005 : 1. [ABSTRACT FROM AUTHOR]

Pitch is a high-quality carbon material precursor due to the characteristics of high carbon and low ash. It is used in the preparation of supercapacitor electrode materials, which not only has a significant effect on widening the application pathway of pitch, but also on the economic efficiency of the coal chemical process.The influence of specific surface area, pore structure and surface properties of carbon materials on the performance of supercapacitors was firstly introduced, and the influence of porous carbon preparation methods（activation method, template method） and pitch pretreatment methods（component separation, pre-oxidation, catalytic polymerization, high temperature polymerization, et al.） on the structure and electrochemical properties of the prepared carbon materials were reviewed. Finally, some further insights into the development of pitch-based porous carbon are proposed. [ABSTRACT FROM AUTHOR]

Titanium, zirconium, and hafnium complexes O[Me2Si(Dip)N]2MCl2 [Dip = 2,6‐iPr2C6H3; M = Ti (1), Zr (2), Hf (3)], O[Me2Si(tBu)N]2ZrCl2 (4), and O[iPr2Si(Dip)N]2ZrCl2 (5) supported by Si‐O‐Si bridged diamido ligands were synthesized. X‐ray diffraction analysis disclosed that complex 2 displays a distorted trigonal bipyramidal geometry. Complexes 1–5, upon the activation with sMAO, exhibited diverse catalytic performance for the polymerization of ethylene and copolymerization of ethylene with norbornene or 1‐octene. For ethylene homopolymerization, both complexes 1–2 are good catalysts giving polymer with high molecular weight and narrow polydispersities. Complex 2 catalyzed copolymerization of ethylene with 1‐octene exhibiting high catalytic activity but with norbornene showing moderate activity, affording corresponding high molecular weight copolymers with relatively high comonomer incorporations of 11% and 29%, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel N^N-bidentate chelate nickel catalyst skeleton with imidazolidin-2-imine/guanidine motif. • High activity and good thermal stability in norbornene (co)polymerization. • Good capacity of norbornene with long-chain-branched 1-alkenes. • Adjustable 1-alkene contents and T g values of cyclic olefin copolymer. • Polar functionalized cyclic olefin copolymer with reasonable incorporations The development of late transition metal catalysts bearing novel ligand platforms is a convenient pathway to obtain prospective systems with enhanced catalytic performance, however, it remains a challenge in the field of olefin (co)polymerizations. In this contribution, a new family of [N,N]-type of bidentate aldimine imidazolidin-2-imine/guanidine ligands and their nickel complexes Ni1 – Ni7 bearing a distinct six-membered chelate ring were successfully synthesized, and characterized. All of the nickel catalysts were active for norbornene polymerization with high activity of up to 7.44 × 105 g mol–1 h−1. These catalysts also copolymerized norbornene and 1-alkenes (1-dodecene and 1-octadecene) while keeping high activities to produce various norbornene-based high-molecular-weight (M n = 5.75–36.0 kg mol−1) cyclic olefin copolymers (COCs) with adjustable 1-alkene incorporations (1.44–13.30 mol%) and a wide range of T g values (102.2–271.4 °C). Moreover, with the decoration of bulky N-aryl substituents, these nickel catalysts exhibited strong tolerance towards polar monomer to promote the direct copolymerization of norbornene and methyl 10-undecenoate with high activity (up to 9.88 × 104 g mol–1 h−1), and furnished polar functionalized COCs with a high molecular weight (M n up to 72.4 kg mol−1) and reasonable polar monomer incorporations (0.19–0.45 mol%). These nickel complexes are rare examples and also promising candidates as catalysts for the efficient synthesis of various COCs. [ABSTRACT FROM AUTHOR]

Here we present a "breathing" nanogel that is fueled by CO2 gas to perform temporally programmable catalytic polymerization. The nanogel is composed of common frustrated Lewis pair polymers (FLPs). Dynamic CO2‐FLP gas‐bridging bonds endow the nanogel with a transient volume contraction, and the resulting proximal effect of bound FLPs unlocks its catalytic capacity toward CO2. Reverse gas depletion via a CO2‐participated polymerization can induce a reverse nanogel expansion, which shuts down the catalytic activity. Control of external factors (fuel level, temperature or additives) can regulate the breathing period, amplitude and lifecycle, so as to affect the catalytic polymerization. Moreover, editing the nanogel breathing procedure can sequentially evoke the copolymerization of CO2 with different epoxide monomers preloaded therein, which allows to obtain block‐tunable copolycarbonates that are unachievable by other methods. This synthetic dissipative system would be function as a prototype of gas‐driven nanosynthesizer. [ABSTRACT FROM AUTHOR]

Here we present a "breathing" nanogel that is fueled by CO2 gas to perform temporally programmable catalytic polymerization. The nanogel is composed of common frustrated Lewis pair polymers (FLPs). Dynamic CO2‐FLP gas‐bridging bonds endow the nanogel with a transient volume contraction, and the resulting proximal effect of bound FLPs unlocks its catalytic capacity toward CO2. Reverse gas depletion via a CO2‐participated polymerization can induce a reverse nanogel expansion, which shuts down the catalytic activity. Control of external factors (fuel level, temperature or additives) can regulate the breathing period, amplitude and lifecycle, so as to affect the catalytic polymerization. Moreover, editing the nanogel breathing procedure can sequentially evoke the copolymerization of CO2 with different epoxide monomers preloaded therein, which allows to obtain block‐tunable copolycarbonates that are unachievable by other methods. This synthetic dissipative system would be function as a prototype of gas‐driven nanosynthesizer. [ABSTRACT FROM AUTHOR]

Atom transfer radical polymerization (ATRP), reversible addition/fragmentation chain transfer polymerization (RAFT), and nitroxide-mediated polymerization (NMP) are common examples of controlled polymerization processes. On the contrary, the Zn complex efficiently catalyzed random I L i -LA/ CL copolymerization; the presence of mono-lactate subunits in the copolymer clearly verified the transesterification mechanism of copolymer formation, and the Al complex was less active. An amazing variety of polymerization mechanisms enables the creation of polymers with given microstructures and comonomer sequences. [Extracted from the article]

The dinuclear aluminum salt {[iBu2(DMA)Al]2(μ-H)}+[B(C6F5)4]− (AlHAl; DMA = N,N-dimethylaniline) is the prototype of a new class of molecular cocatalysts for catalytic olefin polymerization, its modular nature offering easy avenues for tailoring the activator to specific needs. We report here, as proof of concept, a first variant (s-AlHAl) bearing p-hexadecyl-N,N-dimethylaniline (DMAC16) units, which enhances solubility in aliphatic hydrocarbons. The novel s-AlHAl was used successfully as an activator/scavenger in ethylene/1-hexene copolymerization in a high-temperature solution process. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hollow hetero-shell structured CN@C confined graphite N in the inner shell. • The structure regulated the C N and C O and the mass transfer rate. • The reaction rate increased by 503 times. • Removal of BPAF via the polymerization pathway. Lower reaction speed and excessive oxidant inputs impede the removal of contaminants from water via the advanced oxidation processes based on peroxymonosulfate. Herein, we report a new confined catalysis paradigm via the hollow hetero-shell structured CN@C (H-CN@C), which permits effective decontamination through polymerization with faster reaction rates and lower oxidant dosage. The confined space structures regulated the C N and C O and electron density of the inner shell, which increased the electron transfer rate and mass transfer rate. As a result, C N in H-CN@C-10 reacted with peroxymonosulfate in preference to C O to generate singlet oxygen, improving the second-order reaction kinetics by 503 times. The identification of oxidation products implied that bisphenol AF could effectively remove by polymerization, which could reduce carbon dioxide emissions. These favorable properties make the nanoconfined catalytic polymerization of contaminants a remarkably promising nanocatalytic water purification technology. [ABSTRACT FROM AUTHOR]

This paper is a review of studies on the use of the polyhedral oligomeric silsesquioxanes (POSS) of various structures in the synthesis of polyolefins and the modification of their properties, namely: (1) components of organometallic catalytic systems for the polymerization of olefins, (2) comonomers in the copolymerization with ethylene, and (3) fillers in composites based on polyolefins. In addition, studies on the use of new silicon compounds, i.e., siloxane–silsesquioxane resins, as fillers for composites based on polyolefins are presented. The authors dedicate this paper to Professor Bogdan Marciniec on the occasion of his jubilee. [ABSTRACT FROM AUTHOR]

Bio-oil emulsions were stabilized using coconut shell coke, modified amphiphilic graphene oxide, and hydrophobic nano-fumed silica as solid emulsifiers. The effects of different particles on the stability of bio-oil emulsions were discussed. Over 21 days, the average droplet size of raw bio-oil increased by 64.78%, while that of bio-oil Pickering emulsion stabilized by three particles only changed within 20%. The bio-oil Pickering emulsion stabilized by Ni/SiO2 was then used for catalytic hydrodeoxygenation. It was found that the bio-oil undergoes polymerization during catalytic hydrogenation. For raw bio-oil hydrodeoxygenation, the polymerization reaction was little affected by the temperature below 200 °C, but when the temperature raised to 250 °C, it was greatly accelerated. However, the polymerization of monocyclic aromatic compounds in the reaction process was partially inhibited under the bio-oil Pickering emulsion system. Additionally, a GC-MS analysis was performed on raw bio-oil and hydrodeoxygenated bio-oil to compare the change in GC-MS-detectable components after hydrodeoxygenation at 200 °C. The results showed that the Pickering emulsion catalytic system greatly promoted the hydrodeoxygenation of phenolic compounds in bio-oil, with most monocyclic phenolic compounds detected by GC-MS converting to near 100%. [ABSTRACT FROM AUTHOR]

Coordination polymerization of isoprene in the presence of Ziegler–Natta catalytic systems based on a mixture of neodymium and gadolinium bis(2-ethylhexyl) phosphates at the neodymium/gadolinium molar ratios of 25/75, 50/50, and 75/25 was studied. These catalytic systems exhibit high catalytic activity in isoprene polymerization, equal to that of the catalytic system based on neodymium bis(2-ethylhexyl) phosphate. The influence of the Nd/Gd ratio on the molecular-mass characteristics and microstructure of the polymers obtained was examined. The kinetic parameters of the isoprene polymerization using catalytic systems based on a mixture of neodymium and gadolinium salts were determined. The possibility of using such systems in the synthesis of stereoregular cis-1,4-polyisoprene with the optimum level of molecular masses was demonstrated. [ABSTRACT FROM AUTHOR]

To date, nickel(II) complexes have not been practically investigated as catalysts in ring-opening polymerization (ROP) of lactide to produce biodegradable poly(lactic acid), which is in demand in biomedicine and industry. In this study, carboxylate complexes of nickel(II) containing various N-donor ligands with different nuclearity, metal core rigidity and nature of carboxylate ligands were synthesized and studied by infrared spectroscopy, X-ray diffraction, elemental and thermogravimetric analyses. The obtained complexes were examined in the ROP of the rac-lactide in bulk and in toluene solution with and without the addition of a benzyl alcohol initiator. In the series of complexes studied, the complex [Ni(DBED)2(O2CC(CH3)3)2]·(CH3)3CCO2H (DBED is N,N′-dibenzylethylenediamine) was a syndioselective catalyst and showed the highest catalytic ability in the polymerization without the addition of benzyl alcohol. For this complex, according to 1D DOSY 1H NMR spectroscopy and mass spectrometry with electrospray ionization, polymerization is initiated by a free secondary amine, DBED, leaving the metal's inner coordination sphere. Based on the experimental data obtained, a comprehensive density functional theory (DFT) study of the ROP pathways including the initiation and first chain growth cycle steps with a detailed description of the intermediates and evaluation of the energy barriers of the steps was carried out. It was shown that one of the key roles in the reaction process is played by carboxylate ligands, which act as proton carriers from the initiator molecule and have a significant influence on the reactivity of the catalytic metal complexes. [ABSTRACT FROM AUTHOR]

Poly(acrylonitrile- co -butadiene) nanoparticles were synthesized by semibatch microemulsion polymerization. The microstructure of the polymers was characterized by 1H NMR and FT-IR. The particle size of the nitrile butadiene rubber (NBR) latex could be well controlled by reaction temperature, surfactant concentration, and feeding time of monomer. The minimum particle size of 34.2 nm could be achieved by using the surfactant/monomer mass fraction of 7.9 wt%. The latex can be directly catalyzed for hydrogenation using Wilkinson's catalyst (RhCl(PPh 3) 3) and second generation Grubbs catalyst (Grubbs II), respectively. The hydrogenated products (HNBR) with a degree of hydrogenation above 95 mol% were obtained. The fast rate of hydrogenation demonstrates the unique advantages of small particle size. [Display omitted] • NBR particles were synthesized by semibatch microemulsion polymerization. • The smallest particle size with 34 nm can be obtained. • Catalytic hydrogenation of diene-based polymers in aqueous solutions was realized. • Smaller NBR particles have faster mass transfer efficiency and hydrogenation rates. [ABSTRACT FROM AUTHOR]

Zinc-glutarate (ZnGA) is a promising catalyst that can form polymers from CO2 and epoxides, thereby contributing to the development of CO2 utilization technologies and future sustainability. One of the obstacles to commercializing ZnGA in polymer industries is its low catalytic activity. In this study, we introduced activated two-dimensional (2D) ZnGA to improve its catalytic activity in polymerization. The morphology-controlled 2D ZnGA was treated with H3Co(CN)6, and a porous granular-type Co-modified ZnGA (Co-ZnGA) was prepared. The morphology of 2D ZnGA is a prerequisite for the activation by H3Co(CN)6. The catalytic properties of Co-ZnGA were evaluated by copolymerization of various epoxides and CO2, and exhibited catalytic activity of 855, 1540, 1190, and 148 g g-cat−1 with propylene oxide, 1,2-epoxyhexane, 1,2-epoxybutane, and styrene oxide, respectively. This study provided a new strategy using 2D ZnGA instead of conventional ZnGA for increasing the catalytic activity in CO2 polymerization. [ABSTRACT FROM AUTHOR]

Cross‐fractionation characterization (CFC) between temperature rising elution fractionation (TREF) and gel permeation chromatography (GPC) is a technique developed to determine the bivariate molecular weight and chemical composition distribution (MWDxCCD), a unique and detailed microstructural fingerprint of polyolefin. Like other crystallization‐based characterization techniques, CFC may suffer from cocrystallization effects during analysis, which can mislead the interpretation of polymer microstructures. However, cocrystallization phenomena during CFC analysis are not investigated, especially for industrial polymers. In this study, the cocrystallization effect during CFC analysis is systematically investigated using two series of binary blends based on four individual polyethylene samples. These individual samples have distinct microstructural characteristics, representing polyethylene produced using different polymerization processes and catalytic systems. The effects of microstructural characteristics and blending ratio on cocrystallization level are examined. When the CFC profiles of individual components do not overlap, a high level of cocrystallization can be observed. Furthermore, the behavior of how the blending ratio affects cocrystallization depends on the characteristics of CFC profiles of individual component and their interactions. The level of cocrystallization in binary blends increases with the weight fraction of the component having microstructures eluted in the cocrystallization temperature range. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two-in-one organic catalytic system for the polymerization of cyclic carbonates was developed. • The polymerization process was established to be living and controlled. • By DFT theoretical studies and kinetic measurements the active form of the catalyst (dimer) was determined. • The incorporated into the polymer main chain acidic groups were shown to be prone for the post polymerization modification. Trimethylene carbonate, the monomer that can be prepared from CO 2 and 1,3-propanediol, was polymerized cationically, according to the activated monomer mechanism, as it follows from the polymerization kinetics and the DFT studies. Polymerization provides the biocompatible, degradable polymer and was conducted with initiator and catalyst in one molecule (CINICAT). This is in contrast to the known processes when protonic acids (organocatalysts) require addition of an independent initiator and then the low molar mass catalyst, left free in the polymer, may diffuse to its surface, changing the properties. The used CINICAT: hydroxymethylphosphonic acid {HOCH 2 P(=O)(OH) 2 } is quantitatively embedded in the polymer molecules. Polymerization is living/controlled and provides at 100 °C, in bulk, polymers with molar masses ∼104 g/mol. The acidic end groups were further used for polymer functionalization and in reaction with diepoxybutane were quantitatively converted into reactive epoxy groups. [ABSTRACT FROM AUTHOR]

High energy density solid‐state lithium batteries require good ionic conductive solid electrolytes (SE) and stable matching with high‐voltage electrode materials. Here, a highly homogeneous poly(1,3‐dioxolane) composite solid electrolyte (CSE) membrane that can satisfy the above‐mentioned requirements by in situ catalytic polymerization effect of yttria stabilized zirconia (YSZ) nanoparticles on the polymerization of 1,3‐dioxolane (DOL), is reported. The well‐dispersed YSZ nanoparticle catalyst leads to the polymerization conversion of DOL monomers up to 98.5%, which enlarges its electrochemical window exceeding 4.9 V. YSZ also significantly improves the room temperature ionic conductivity (2.75 × 10−4 S cm−1) and enhances the cycle life of lithium metal anode. Based on this CSE, the Li(Ni0.6Co0.2Mn0.2)O2 (NCM622)‐based solid‐state lithium battery shows a long cycle life over 800 cycles. This investigation encourages polymer SE toward practical high energy solid‐state batteries. [ABSTRACT FROM AUTHOR]

Significant agricultural and industrial activities necessitate the regular monitoring of nitrate (NO3−) ions levels in feed and groundwater. The current comparative study discloses an innovative user-friendly electrochemical approach for the determination of NO3− over polyaniline (PAni)-based modified electrodes. The electrochemical sensors concocted with PAni, multi-walled carbon nanotubes (CNT), and gum arabic (GA). The unique electrode material GA@PAni-CNT was synthesized by facile one-pot catalytic polymerization of aniline (Ani) with FeCl3/H2O2 in the presence of CNT and GA as integral components. As revealed by cyclic voltammetry (CV), the anchoring/retention of NO3− followed by reduction is proposed to occur when a GA@PAni-CNT electrode is immersed in phosphate buffer electrolyte containing NO3− that eventually results in a significantly higher redox activity of the GA@PAni-CNT electrode upon potential scan. The mechanism of NO3− anchoring may be associated with the non-redox transition of leucomeraldine salt (LS) into emeraldine salt (ES) and the generation of nitrite (NO2−) ions. As a result, the oxidation current produced by CV for redox transition of ES ↔ pernigraniline (PN) was ~9 times of that obtained with GA@PAni-CNT electrode and phosphate buffer electrolyte, thus achieving indirect NO3− voltammetric determination of the GA@PAni-CNT electrode. The prepared GA@PAni-CNT electrode displayed a higher charge transfer ability as compared to that of PAni-CNT and PAni electrodes. The optimum square wave voltammetric (SWV) response resulted in two linear concentration ranges of 1–10 (R2 = 0.9995) and 15–50 µM (R2 = 0.9988) with a detection limit of 0.42 µM, which is significantly lower. The GA@PAni-CNT electrode demonstrated the best detection, sensitivity, and performance among the investigated electrodes for indirect voltammetric determination of NO3− that portrayed the possibility of utilizing GA—stabilized PAni and CNT nanocomposite materials in additional electrochemical sensing applications. [ABSTRACT FROM AUTHOR]

This work studied two different methodologies for the synthesis of poly(p-phenylene) (PPP) via Kumada Catalytic Transfer Polymerization (KCPT). The first methodology varied reaction time, temperature, and proportion of catalyst. The second methodology varied temperature, type of Grignard reagent, type of catalyst, and amount of monomer. The polymer formation was observed only using a high quantity of monomers (second study). The gel permeation chromatography results showed a significant difference in the Mn and PDI of the obtained polymers (for instance, Mn = 4.9 kDa, PDI = 1.23, and Mn = 34.6 kDa, PDI = 1.47). UV–vis analyses showed a redshift compared to monomer due to conjugated polymer chains forming with maximum absorbance at 338 nm and 339 nm, respectively. Cyclic voltammetry showed a high Eg value between 3.22 eV and 3.25 eV; a blue emission was also observed in the qualitative fluorescence test under 365 nm excitation, and photoluminescence spectra showed a deep blue emission at 410 nm as well as a narrow FWHM < 80 nm. KCTP was shown to significantly depend on the reaction parameters, mainly on the Grignard reagent and catalyst types. The synthesized PPPs have potential applicability as a fluorescent emitter in OLED due to their high Eg, low wavelength absorption, and apparent blue emission under 365 nm irradiation. [ABSTRACT FROM AUTHOR]

The reduction of 2‐[(2,6‐diisopropylphenyl)imino]acenaphthen‐1‐one (dpp‐MIAN) with metallic calcium in THF affords tetrameric [(dpp‐MIAN)Ca(THF)]4 (1). A further addition of dpp‐MIAN to complex 1 leads to the formation of paramagnetic species [(dpp‐MIAN)3Ca]2Ca (2). Both complexes were characterized by X‐ray diffraction. Complex 1 is active towards phenylacetylene and acetylene at temperatures above 80 °C. As a result, cycloaddition products are formed. Their hydrolysis results in a release of the dpp‐MIAN ligand with an attached phenylethynyl or ethynyl moiety to the carbonyl C atom. Complexes 1 and 2 demonstrate catalytic activity in the polymerization of L‐lactide both in solution and in bulk. [ABSTRACT FROM AUTHOR]

The ring-opening copolymerization (ROP) of hexaethylcyclotrisiloxane (E3) and 1,3,5-trimethyl-1,3,5-tri(3,3,3- trifluoropropyl) cyclotrisiloxane (F3) was catalyzed by organic cyclotrisiloxane base (CTPB) under mild conditions. CTPB showed high catalytic activity for the polymerization of E3 and F3. Linear polydiethylsiloxanes (PDES) and poly(diethyl-rantrifluoropropylmethyl) siloxanes (PDES-ran-PTFPMS) with different mole fractions of trifluoropropylmethyl siloxane group (F unit) (mole fraction (fF): 0−46%) were successfully synthesized. The composition and structure of the PDES-ran-PTFPMS copolysiloxanes were characterized in detail by gel permeation chromatography (GPC) and nuclear magnetic resonance (NMR), and the glass transition temperature (Tg) and crystallization behavior of the polymers were comprehensively analyzed by differential scanning calorimetry, and the water-oil contact angle of fluorine-containing polyethylsiloxane film was investigated by microscopic contact angle test. The chemical positions of the resonance peaks in the nuclear magnetic resonance spectrum (1H-NMR and 29Si-NMR) were analyzed, indicating that the PDES-ran-PTFPMS was successfully prepared. The results of differential scanning calorimeter (DSC) indicated that the crystallization of polydiethylsiloxane at low temperature can be entirely inhibited by the introduction of F unit. The obtained PDES-ran-PTFPMS has a low glass transition temperature Tg (−134 ℃), has very excellent low temperature performance, and is an ideal precursor material for low temperature resistant rubber materials. When fF is higher than 6.0%, the crystallization behavior was inhibited. The results of contact angle test of fluorine-containing polyethylsiloxane film demonstrated that the introduction of F unit into the PDES chain can effectively improve its hydrophobicity and decrease the oil wettability. [ABSTRACT FROM AUTHOR]

A proof‐of‐concept study of hypervalent chalcogenonium⋅⋅⋅π bonding catalysis was performed. A new catalytic strategy using 1,2‐oxaselenolium salts as chalcogen bond donors and alkenes as chalcogen bond acceptors is described. The feasibility of this concept is demonstrated by the use of trisubstituted selenonium salts in the metal‐free catalytic hydrofunctionalization and polymerization of alkenes via unconventional seleniranium ion‐like intermediates. The results indicate that counter anions have a significant effect on the catalysis based on hypervalent chalcogenonium⋅⋅⋅π bonding interactions. [ABSTRACT FROM AUTHOR]

A proof‐of‐concept study of hypervalent chalcogenonium⋅⋅⋅π bonding catalysis was performed. A new catalytic strategy using 1,2‐oxaselenolium salts as chalcogen bond donors and alkenes as chalcogen bond acceptors is described. The feasibility of this concept is demonstrated by the use of trisubstituted selenonium salts in the metal‐free catalytic hydrofunctionalization and polymerization of alkenes via unconventional seleniranium ion‐like intermediates. The results indicate that counter anions have a significant effect on the catalysis based on hypervalent chalcogenonium⋅⋅⋅π bonding interactions. [ABSTRACT FROM AUTHOR]

Living polymerization by suppressing chain transfer is a very useful method for achieving precise molecular weight and structure control. However, the suppression of chain transfer at high temperatures is extremely challenging in any catalytic polymerization. This has been a severe limitation for catalytic olefin polymerization, which is one of the most important chemical reactions. Here, we report the unprecedented living polymerization of ethylene at 130 °C, with a narrow molecular weight distribution range of 1.04 to 1.08. This is a significant increase in the reaction temperature. Tailor‐made α‐diimine nickel catalysts that exhibit both the steric shielding and fluorine effects play an essential role in this breakthrough. These nickel catalysts are even active at 200 °C, and enable the formation of semi‐crystalline, ultrahigh‐molecular‐weight polyethylene at 150 °C. Mechanistic insights into the key chain transfer reaction are elucidated by density functional theory calculations. [ABSTRACT FROM AUTHOR]

Living polymerization by suppressing chain transfer is a very useful method for achieving precise molecular weight and structure control. However, the suppression of chain transfer at high temperatures is extremely challenging in any catalytic polymerization. This has been a severe limitation for catalytic olefin polymerization, which is one of the most important chemical reactions. Here, we report the unprecedented living polymerization of ethylene at 130 °C, with a narrow molecular weight distribution range of 1.04 to 1.08. This is a significant increase in the reaction temperature. Tailor‐made α‐diimine nickel catalysts that exhibit both the steric shielding and fluorine effects play an essential role in this breakthrough. These nickel catalysts are even active at 200 °C, and enable the formation of semi‐crystalline, ultrahigh‐molecular‐weight polyethylene at 150 °C. Mechanistic insights into the key chain transfer reaction are elucidated by density functional theory calculations. [ABSTRACT FROM AUTHOR]

Au-embedded MCM-41 was firstly employed as an electrolyte additive to feasibly form a robust organic/inorganic hybrid solid electrolyte interphase (SEI). Such SEI derived from the combination of the Si-O segment of MCM-41 and the poly(CO 3) oligomer via the Au-induced electrocatalytic polymerization of EC possesses an ultrahigh Young's modulus to effectively prevent the growth of lithium dendrites. [Display omitted] • Au as an electrocatalyst was firstly introduced into the electrolyte via the MCM-41 carrier. • An organic/inorganic hybrid SEI layer induced by Au@MCM-41 with an ultrahigh Young's modulus was in situ formed on Li anode, effectively suppressing lithium dendrites. • High-performance lithium metal batteries were achieved with the Au@MCM-41-modified electrolyte. The solid electrolyte interphase (SEI) determines the lithium (Li) deposition behavior for long-term lithium metal batteries. However, the naturally formed fragile SEI would cause the nonuniform lithium deposition and random dendrite growth due to weak interaction of the heterogeneous distributed inorganic and organic species. Herein, we designed Au-embedded mesoporous molecular sieve as an electrolyte modifier to feasibly form a robust organic/inorganic hybrid SEI. Such hybrid SEIs, composed of Si-O interlinked polycarbonates (poly(CO 3)) which is derived from the Au-induced electrocatalytic polymerization of EC (ethylene carbonate), possess an ultrahigh Young's modulus of 11.6 GPa, achieving uniform lithium deposition and suppression of lithium dendrites. Assembled by the Au@MCM-41-modified electrolyte, the Li||Li symmetrical cells exhibit a recyclable behavior of Li deposition/dissolution over 900 h at 0.5 mA cm−2, and the Li||LFP (LiFePO 4) full cells maintain a high capacity of 123 mAh g−1 even after 300 cycles at 1.0 C. This work explores a new route to in situ develop a robust and effective SEI for prospective lithium metal batteries in practical application and social requirement. [ABSTRACT FROM AUTHOR]

• Persulfate-induced polymerization of organic pollutants (Poly-PS-AOPs) is reviewed. • In-depth correlations of catalysts, PS, and organics with polymeric mechanisms are highlighted. • Partial or complete polymeric degradation and synthesis by Poly-PS-AOPs are introduced. • Challenges and perspectives of Poly-PS-AOPs techniques are presented. Catalytic polymerization pathways in advanced oxidation processes (AOPs) have recently drawn much attention for organic pollutant elimination owing to the rapid removal kinetics, high selectivity, and recovery of organic carbon from wastewater. This work presents a review on the polymerization regimes in AOPs and their applications in wastewater decontamination. The review mainly highlights three critical issues in polymerization reactions induced by persulfate activation (Poly-PS-AOPs), including heterogeneous catalysts, persulfate activation pathways, and properties of organic substrates. The dominant influencing factors on the selection of catalysts, activation regimes of reactive oxygen species, and polymerization processes of organic substrates are discussed in detail. Moreover, we systematically demonstrate the merits and challenges of Poly-PS-AOPs upon pollutant degradation and polymer synthesis. We particularly highlight that Poly-PS-AOPs technology could be promising in the treatment of industrial wastewater containing heterocyclic organics and the synthesis of polymers and polymer-functionalized materials for advanced environmental and energy applications. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • CuO@CuCe y O 1+2y+x/2 -IE is prepared for catalytic oxidative polymerization. • More than 80% of phenolic contaminants are converted into polyphenols and recycled. • Cu(III) formed on catalyst surface promote O 2 •− conversion to 1O 2. • 1O 2 attack phenolic hydroxyl group with production of phenoxenium ion. • C-O coupling make phenoxenium ion form polyphenolic polymers. A novel approach for selective removal of phenolic contaminants and polyphenols recycling based on oxidative polymerization is explored, which is significantly different from conventional degradation processes. Plenty of bridging OH− and lattice oxygen are bound on CuO@CuCe y O 1+2y+x/2 -IE due to strong coordination between Ce and O, which induced formation of Cu(III) with high redox potential. Cu(III) could not only form outer-sphere complexation with peroxymonosulfate (PMS) for enhancement of O 2 •– production involving series of chain reactions, but also promote O 2 •– conversion to singlet oxygen (1O 2). Owing to electrophilicity, 1O 2 preferentially attacked the phenolic hydroxyl group with the production of phenoxeniums ions, and phenoxide ions could immediately couple with negatively charged hydroxyl groups of other bisphenol A (BPA) molecular so as to make polymer chains get a sustained growth over CuO@CuCe y O 1+2y+x/2 -IE. Thus, CuO@CuCe y O 1+2y+x/2 -IE can selectively remove phenolic contaminants from water with low oxidant consumption, and simultaneously recycle more than 80 % of polyphenols. In summary, the present work demonstrated the predominant role and mechanism of 1O 2 in triggering the oxidative polymerization of BPA, which contributed to construction of cost-efficient catalytic system for phenolic contaminants conversion into polyphenols. [ABSTRACT FROM AUTHOR]

In this work, the polymerization of hydrophobic pentafluorophenylethyl into the high conductivity poly (acenaphthenyl aryl piperidinium) backbone was catalyzed by an efficient and facile one-pot method with super-strong acids to build enhanced phase separation structures while maintaining low swelling. The prepared QPANTP-20-F 15 membrane exhibited the most significant hydrophilic-hydrophobic separation phenomenon, with the conductivity as high as 192.19 mS cm−1 at 80 °C. Due to the incorporation of hydrophobic fluorinated groups, the water uptake of the membrane was limited, and its mechanical (71.0 MPa under hydrated condition) and dimensional stability property (11.32% swelling) showed improved results. In addition, after 1200 h at 80 °C in 3 M/5 M NaOH solution, the structure of the prepared polymer exhibited excellent chemical stability property, with conductivity remaining of 95.04% and 86.38%, respectively. With current density of 706 mA cm−2 at 80 °C, the AEMFCs achieved a peak power density of 321 mW cm−2. [Display omitted] • The "one-pot" catalytic polymerization method was convenient and efficient, and the subsequent products were easy to purify. • The selected poly (acenaphthylenyl aryl piperidinium) was highly conductive polymer backbone due to the presence of π-π interaction. • The introduction of fluorinated group enhanced the microphase separation structure to facilitate the effective OH- conduction. [ABSTRACT FROM AUTHOR]

Ethylene-propylene-diene rubbers (EPDM) are one of the most important polyolefin materials widely commercialized and used in various industries in recent years. The production of EPDM is based solely on catalytic coordination polymerization processes. The development of new catalysts and processes for the synthesis of EPDM has expanded the range of products and their manufacturing in terms of energy efficiency, processability, and environmental safety. This mini-review mainly analyzes patented data on the synthesis of EPDM on new-generation single-site catalytic systems based on Group IVB complexes including the systems commercialized by major manufacturers of EPDM. The advantages of these systems are evident in comparison with conventional vanadium systems introduced into production in the 1960s and used to date in the industrial synthesis of EPDM. [ABSTRACT FROM AUTHOR]