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Light‐responsive polymers are a prospective area of smart materials. The increasing number of potential applications of these materials require the development of new polymers sensitive to external irradiation. However, most of the polymers reported so far are represented by poly(meth)acrylates. In this work, the straightforward approach is proposed to the synthesis of light‐responsive poly(2‐oxazoline)s via cationic ring‐opening polymerization of 2‐azobenzenyl‐2‐oxazoline (2‐(4‐(phenyldiazenyl)phenyl)‐2‐oxazoline). Polymerization kinetics studies reveal significant activity of the new monomer in both homopolymerization and copolymerization with 2‐ethyl‐2‐oxazoline. The difference in monomer reactivity allows obtaining both gradient and block copolymers via simultaneous or subsequent one‐pot polymerization, respectively, leading to a set of well‐defined gradient and block copoly(2‐oxazoline)s with 10–40% of azobenzene units. Due to their amphiphilic nature, the materials self‐assemble in water, which is proven by dynamic light scattering and transmission electron microscopy. The change in polarity caused by the isomerization of azobenzene fragments in response to UV light irradiation results in a change of nanoparticle size. The obtained results provide a new impulse for the development of light‐responsive materials based on poly(2‐oxazoline)s. [ABSTRACT FROM AUTHOR]

Chemiluminescence (CL) has recently emerged as a novel light source for triggering various photoreactions with appealing features such as the elimination of continuous power supply and complex instrumentation. Here, CL‐induced cationic photopolymerization using ferrocenium salts as unimolecular photoinitiators is reported. The ferrocenium salts, facilely synthesized via ligand exchange reactions, absorb the visible light emitted from CL reactions and generate Lewis acids capable of initiating the cationic polymerization of oxirane and vinyl monomers. The presented method can be applied to create linear polymer chains and cross‐linked luminescent polymer networks, which have significant potential in the fabrication of new polymeric materials and various bioapplications. [ABSTRACT FROM AUTHOR]

Based on the chemical fingerprint development method, this science popularization project has designed a variety of different science experiments to show the principle and characteristics of chemical fingerprint development to the science popularization target comprehensively. In the mode of science popularization, the project innovatively combines “online + offline” mode and “home + laboratory” environment, which breaks the limitation of time, space and equipment in traditional science popularization and greatly expands the scope and breadth of science popularization. In addition, in the implementation of specific science popularization, the project focuses on the improvement of scientific and cultural literacy of science popularization targets, opening up the public’s vision, and achieving scientific and effective disinformation. [ABSTRACT FROM AUTHOR]

Methacrylation was performed on fibrinogen to design a new biomedical hydrogel for 3D cell culture or as a biodegradable delivery matrix for in vivo implantation. The methacrylation of denatured fibrinogen in solution was performed using methacrylic anhydride (MAA). The extent of fibrinogen methacrylation was quantified by proton NMR and controlled using stochiometric quantities of MAA during the reaction. The methacrylated fibrinogen (FibMA) hydrogels were formed by light-activated free-radical polymerization in the presence of macromolecular cross-linking polymers made from acrylated poly(ethylene glycol) (PEG). The biocompatibility and biodegradability of the FibMA hydrogels were characterized by in vitro assays and in vivo implantation experiments using quantitative magnetic resonance imaging (MRI) of the implant volume. The FibMA supported the growth and metabolic activity of human dermal fibroblasts in both 2D and 3D cultures. The methacrylation did not alter important biological attributes of the fibrinogen, including the ability to support cell adhesion and 3D cell culture, as well as to undergo proteolysis. Animal experiments confirmed the biodegradability of the FibMA for potential use as a scaffold in tissue engineering, as a bioink for 3D bioprinting, or as a biodegradable matrix for in vivo sustained delivery of bioactive factors. This paper describes methacrylated fibrinogen (FibMA) and the formation of a biomedical hydrogel from FibMA for cell culture and other biomedical applications. Inspired from methacrylated gelatin (GelMA), the FibMA is made from blood-derived fibrinogen which is more suitable for clinical use. Sharing similar properties to other hydrogels made from methacrylated proteins, the FibMA has yet to be reported in the literature. In this manuscript, we provide the methodology to produce the FibMA hydrogels, we document the mechanical versatility of this new biomaterial, and we show the biocompatibility using 3D cell culture studies and in vivo implantations. [Display omitted] [ABSTRACT FROM AUTHOR]

Exploiting non‐covalent interactions to catalyze challenging ionic polymerizations is an ambitious goal but is in its infancy. We recently demonstrated non‐covalent anion‐binding catalysis as an effective methodology to enable living cationic polymerization (LCP) of vinyl ethers in an environmentally benign manner. Here, we further elucidate the structure‐reactivity relationships of the elaborately designed seleno‐cyclodiphosph(V)azanes catalysts and the roles of anion‐binding interactions by a combined theoretical DFT study and experimental study. The investigation suggests that the distinct cis‐cyclodiphosph(V)azane framework combined with "selenium effect" and electron‐withdrawing 3,5‐(CF3)2‐Phenyl substitution pattern in catalyst enables a critical contribution to accessing excellent stability, anion affinity and solubility under polymerization conditions. Thus, the catalyst could leverage anion‐binding interactions to precisely control reversible and transient dormant‐active species equilibrium, allowing it to dynamically bind, recognize and pre‐organize propagating ionic species and monomer, thereby facilitating efficient chain propagation and minimizing irreversible chain transfer events under mild conditions. The more in‐depth understanding of the mechanism for anion‐binding catalytic LCP reported herein should help to guide future catalyst design and to extend this concept to broader polymerization systems where ionic species serve as crucial intermediates. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Covalent/metal organic frameworks are highly attractive due to their tunable structure and properties, and broad applications in multiple fields. However, they still suffer from numbers of drawbacks including low solubility, harsh synthesis and fabrication, and low mechanical flexibility. Herein, we report a new organic framework consisting of macrocycles and organic frames in its periodic structure, and denote it as macrocycle organic polymer (MOP). The size‐tunable macrocycles containing peripheral furan units are synthesized by anionic ring‐opening polymerization, which undergo a reversible Diels‐Alde reaction with bismaleimide to generate/degrade MOPs at given temperatures. Relying on above features, MOPs exhibit excellent flexibility, healable ability and recycle ability. Interestingly, owing to the "living" nature of anionic ring‐opening polymerization, MOPs can self‐grow into bigger sizes in the presence of monomer and catalysis, analogs to the living creatures. Moreover, their high porosity and rich thioether structure enable them as good metal ion absorbers and promising applications in wearable electronics. [ABSTRACT FROM AUTHOR]

Photocurable polymer provides fast curable properties via ultraviolet (UV) light for 3D‐printed propellants. This work outlines the preparation and characterization of photocurable fluorinated polyether‐based reactive inks. Acrylate‐terminated poly‐2‐((2,2,3,3,3‐pentafluoropropoxy)‐methyl) ethylene oxide (P5F‐AA) was synthesized as photocurable binder through the esterification of acrylic acid, and the terminal hydroxyl group of poly‐2‐((2,2,3,3,3‐pentafluoropropoxy)‐methyl) ethylene oxide (P5F), which was synthesized through cationic ring‐opening polymerization of 2‐((2,2,3,3,3‐pentafluoropropoxy)methyl) oxy‐ethane (PFEE) by using butane diol as initiator. In comparison with P5F, P5F‐AA had a lower glass transition temperature (Tg) of −63.3°C. A new type of photocurable resin, which may be used for additive manufacturing of energetic materials, was prepared via UV radiation in an LED UV curing tank by using P5F‐AA as prepolymer, diphenyl (2,4,6‐trimethyl benzoyl) phosphine oxide (TPO) as photo‐initiator, and tri‐fluoroethyl acrylate (3F‐AA) and 1,6‐hexanediol diacrylate (HDDA) as mono‐ and multifunctional diluents, respectively. When the mass ratio of P5F‐AA/3F‐AA/HDDA binder matrix was 1:1:0.5, the sample exhibited maximal mechanical strength of 6.56 MPa with elongation at break of 13.38%, which was due to the introduction of HDDA effectively increasing the "entanglement" between molecular chains. Thermogravimetric analysis (TGA‐DTG) was utilized to evaluate the ability to decompose thermally of the binder matrix, and the results showed the initial degradation temperature started at nearly 181°C and two consecutive stages in thermal decomposition. Overall, the obtained results from the different techniques suggested that P5F‐AA/3F‐AA/HDDA binder matrix may be a photocurable reactive ink for 3D‐printed propellants, which would provide a certain reference value and guiding importance for design of reactive inks. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Covalent/metal organic frameworks are highly attractive due to their tunable structure and properties, and broad applications in multiple fields. However, they still suffer from numbers of drawbacks including low solubility, harsh synthesis and fabrication, and low mechanical flexibility. Herein, we report a new organic framework consisting of macrocycles and organic frames in its periodic structure, and denote it as macrocycle organic polymer (MOP). The size‐tunable macrocycles containing peripheral furan units are synthesized by anionic ring‐opening polymerization, which undergo a reversible Diels‐Alde reaction with bismaleimide to generate/degrade MOPs at given temperatures. Relying on above features, MOPs exhibit excellent flexibility, healable ability and recycle ability. Interestingly, owing to the "living" nature of anionic ring‐opening polymerization, MOPs can self‐grow into bigger sizes in the presence of monomer and catalysis, analogs to the living creatures. Moreover, their high porosity and rich thioether structure enable them as good metal ion absorbers and promising applications in wearable electronics. [ABSTRACT FROM AUTHOR]

Lithium metal batteries are highly pursued for energy storage applications due to superior energy densities. However, fast battery decay accompanied by lithium dendrite growth occurs mainly owing to solid electrolyte interphase (SEI) failure. To address this, a novel functional quasi‐solid‐state polymer electrolyte is developed through in situ copolymerization of a cyclic carbonate‐containing acrylate and a urea‐based acrylate monomer in commercial available electrolyte. Based on the rigid‐tough coupling design of SEI, anionic polymerization of cyclic carbonate units and reversible hydrogen bonding formed using urea motifs on the polymer matrix can take place at SEI. This mechanically stabilizes SEI and thus helps achieve uniform lithium deposition behaviors and non‐dendrite growth. Thus, the superior cycling performance of LiNi0.6Co0.2Mn0.2O2/Li metal batteries is promoted by the formation of compatible SEI. This design philosophy to build mechanochemically stable SEI provides a good example for realizing advanced lithium metal batteries. [ABSTRACT FROM AUTHOR]

Cationic polymerization of ɛ-caprolactone (CL) mediated by anhydrous iron (III) chloride (FeCl3) or FeCl3/nH2O systems (where n = 2, 4, 6 and 8) was investigated. Reaction proceeded in tetrahydrofuran solution at room temperature. Analysis of polymers by MALDI-TOF technique revealed in both cases the formation of linear as well as cyclic PCLs macromolecules. It was proposed, that in the presence of anhydrous FeCl3 polymerization occurs by active chain end (ACE) mechanism accompanied by inter- and intramolecular transesterification, the latter leads to the formation of cyclic macromolecules. However, in the systems containing water two mechanisms operate simultaneously, i.e. ACE ones and activated monomer (AM) mechanism mediated witch FeCl3 (catalyst)/H2O (initiator) system, which prevails and results exclusively in linear macromolecules. Unexpectedly, methanol and dipropylene glycol used as hydroxylic additives to FeCl3/6H2O system were inert in the polymerization. Moreover, synthesized polymers appeared to be polymodal. The results obtained differ strongly from reported previously. The course of the studied processes was discussed. Molar masses and dispersities of polymers were determined by means of size exclusion chromatography (SEC). 13C nuclear magnetic resonance (NMR) was also used for analysis of the polymers. Thermal properties of the polymers obtained were also examined. Wide angle X-ray scattering was used to characterize phase composition of PCL. [ABSTRACT FROM AUTHOR]

The aim of the present study is to examine the evolution of monomer conversion during suspension free radical polymerization of methyl methacrylate (MMA) at 80 °C, both in the presence and absence of nanocellulose obtained via TEMPO oxidation. The main focus of this work is on the kinetic aspects of MMA polymerization, particularly the diffusive step of the termination reaction and its impact on polymeric radicals. Experimental conversion evolutions are tracked using gravimetry. In addition, we employed an existing mathematical model to describe the effects of nanocellulose during polymerization, using the Einstein diffusion equation, geometric considerations and an approach that accounts for termination between short and long polymeric radicals. This model explains the evolution of monomer conversion regarding the effects produced by nanocellulose during the free radical polymerization reactions, focusing on factors that affect the diffusive termination step as difficulties for the short polymeric radicals reacting with the long radicals and the decrease of the segmental mobility. Our experimental results exhibit a premature autoacceleration with the presence of nanocellulose during polymerization reactions. Based on the adjustments made to the model, the theoretical results suggest that this reaction behavior is due to the impact of nanocellulose on the termination stage, which hinders a successful termination collision between short and long polymeric radicals while decreasing the segmental mobility of long radicals. Therefore, at higher nanocellulose content, the termination coefficient is reduced further. [ABSTRACT FROM AUTHOR]

In this research, functionalization of the easily available polyalphaolefin (PAO) based resins is accomplished by the copolymerization of 1-decene with 9-decenol through a facile cationic polymerization route. The resultant co-oligomer was further functionalized with acryloyl chloride to synthesize a macromer product. The exact microstructure of synthesized and modified resins was explored via H-NMR, FTIR and GPC analytical methods. The PAO chains contain roughly 20 monomeric units in which three polymerizable C = C moieties could be embedded. The crosslinking of macromer started by visible light irradiation provided final fabricate. The effect of photo-initiator content on the cross-linking kinetics of the resin was explored using shrinkage strain measurement. The resulting three-dimensional PAO (3D-PO) revealed hydrophilic nature with water contact angle of 65° and excellent cell viability of 93% in the MTT assay. This strategy starts from easily available α-olefin based monomers, employs a facile cationic polymerization procedure, enables modulation of the functional groups in the macromer backbone in order to make it photo-polymerizable, and holds great potential for tissue engineering applications. [ABSTRACT FROM AUTHOR]

Synthesis of poly(epichlorohydrin-g-4-vinylbenzyl-g-methyl methacrylate) [poly(ECH-g-VB-g-MMA)] graft copolymer was carried out by cationic ring-opening polymerization (ROP), reversible addition-fragmentation chain transfer (RAFT) polymerization, and atom transfer radical polymerization (ATRP) methods. In the first stage, poly(epichlorohydrin) [PECH] was synthesized using epichlorohydrin monomer by ROP. In the second stage, macro-RAFT agent was synthesized by a chemical reaction of PECH with potassium ethyl xanthogenate. In the third stage, macro-RAFT agent and 4-vinylbenzyl chloride were used to obtain poly(ECH-g-VBC) graft copolymer by RAFT polymerization. In the last stage, in the ATRP of the methyl methacrylate, chloromethyl groups of the poly4-vinylbenzyl chloride segment of poly(ECH-g-VBC) graft copolymer were used as the starting functional group, poly(ECH-g-VB-g-MMA) graft copolymer with low dispersity was obtained as a result of the polymerization. The product characterization was fulfilled using spectroscopic and thermal analysis techniques such as 1H-NMR, FT-IR, TGA, SEM and GPC instruments. [ABSTRACT FROM AUTHOR]

Recently, biotin (vitamin H) has been described as a ligand for active targeting and it has been found that many cancer cells overexpress the biotin receptor. In this study a biotin‐conjugated block copolymer, biotin‐poly(2‐ethyl‐2‐oxazoline)‐block‐poly{N '‐[N‐(2‐aminoethyl)‐2‐aminoethyl]aspartamide} (biotin‐pEtOx‐b‐pASP(DEA) is synthesized by a living cationic polymerization of the pEtOx‐block followed by the nucleophilic ringopening polymerization of the pASP‐block. The biotin moiety is coupled to the pEtOx‐b‐pASP precursor by a Cu(I) mediated azide‐alkyne click chemistry and finally, the diethylamine (DEA) side chain is introduced by a polymer analogous reaction. The final polymer P1 formed polyplexes in the presence of plasmid DNA that are characterized with respect to N/P ratio, size, zeta potential, and shape compared to a control polymer P2 without biotin. In addition, HEK293 cells are transfected with these polyplexes and the number of fluorescent HEK293 cells is evaluated to assess the influence of polymer nature on the activity of the micelles. Flow cytometric analysis revealed a significantly higher uptake of the biotin‐PEtOx‐PASP(DEA)/pDNA micelle than the PEtOx‐PASP(DEA)/pDNA micelle against HEK293 cells at a low N/P ratio of 20, consistent with the transfection results whereas at higher N/P ratio no difference can be observed anymore between the two polymers. [ABSTRACT FROM AUTHOR]

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[Display omitted] Thermosensitivestar-shapedpoly- N -acyl-1,3-propylenimines with a macrocyclic trianglamine core were synthesized using a 'grafting-on' approach involving polymerization of 2-alkyl-5,6-dihydro-4 H -oxazines at free trianglamine. The resulting polymers form complexes with europium ions and curcumin and can be used in the creation of delivery systems for drugs as well as contrast agents for NMR tomography. [ABSTRACT FROM AUTHOR]

There have been reports on different types of porous polymer films for various applications. The designing of such porous films with uniform properties is a challenging task. In this work, tunable porous thin films of poly(N‐isopropylacrylamide) (pNIPAM) and polycaprolactone (PCL), that is, (pNIPAM)‐b‐(PCL) has been fabricated and its sustained drug delivery applications have been reported. First, the (pNIPAM)‐b‐(PCL) has been synthesized through the addition polymerization of pNIPAM and PCL. Then the synthesized (pNIPAM)‐b‐(PCL) has been used to design porous thin film with varying temperatures without using any external template, below and above the lower critical solution temperatures (LCST) of pNIPAM. Pore size in (pNIPAM)‐b‐(PCL) films has been tuned by varying the temperature from ~10 to 40°C. Then the developed thermosensitive porous film has been taken and seeded with the K562 (chronic myeloid leukemia blood cancer) and HepG2 (hepatocarcinoma) cells and the skin cancer cells (B16‐F10) killing efficiency of anticancer drug (e.g., doxorubicin hydrochloride, DOX) loaded (pNIPAM)‐b‐(PCL) film has been studied. It is found that the DOX‐loaded (pNIPAM)‐b‐(PCL) can efficiently kill the skin cancer cells. The porous polymer thin film reported in this work can be a versatile platform for the loading of drugs and it can be used for the various therapeutic applications. [ABSTRACT FROM AUTHOR]

On the basis of synthesizing a highly efficient chain‐transfer agent ethyl (1‐isobutoxyethyl) carbonotrithioate(CTA), living cationic polymerization of isobutyl vinyl ether (IBVE) was successfully initiated by visible light catalysis. The random copolymerization of isobutyl vinyl ether and propyl vinyl ether (PVE), cyclohexyl vinyl ether (CyVE), and 2‐chloroethyl vinyl ether (CEVE) was achieved on the basis of investigating the reactivity ratios of vinyl ether monomers. The influence of photocatalyst (PC) concentration and wavelength on the copolymerizations was investigated. It was found that high PC concentration results in a fast polymerization rate. The wavelength of the blue LED was most suitable for this reaction system. This photocatalytic reaction provides a new way for molecular design of cationic polymerization. [ABSTRACT FROM AUTHOR]

Fully room temperature three-dimensional (3D) shape-reprogrammable, recyclable, and photomobile azobenzene (azo) polymer actuators hold much promise in many photoactuating applications, but their development is challenging. Herein, we report on the efficient synthesis of a series of main-chain azo liquid crystalline polymers (LCPs) with such performances via Michael addition polymerization. They have both ester groups and two kinds of hydrogen bond-forming groups (i.e., amide and secondary amino groups) and different flexible spacer length in the backbones. Such poly(ester-amide-secondary amine)s (PEAsAs) show low glass transition temperatures (Tg ≤ 18.4 °C), highly ordered smectic liquid crystalline phases, and reversible photoresponsivity. Their uniaxially oriented fibers fabricated via the melt spinning method exhibit good mechanical strength and photoinduced reversible bending/unbending and large stress at room temperature, which are largely influenced by the flexible spacer length of the polymers. Importantly, all these fibers can be easily reprogrammed under strain at 25 °C into stable fiber springs capable of showing a totally different photomobile mode (i.e., unwinding/winding), mainly owing to the presence of low Tg and both dynamic hydrogen bonding and stable crystalline domains (induced by the uniaxial drawing during the fiber formation). They can also be recycled from a solution at 25 °C. This work not only presents the first azo LCPs with 3D shape reprogrammability, recyclability, and photomobility at room temperature, but also provides some important knowledge of their structure–property relationship, which is useful for designing more advanced photodeformable azo polymers. [ABSTRACT FROM AUTHOR]

In this study, a self‐healing nanocomposite hydrogel (NC hydrogel) loaded with sodium citrate (SC) corrosion inhibitor was developed. NC hydrogels were synthesized through free‐radical polymerization of N, N'‐Dimethylacrylamide (DMA) within a dispersion of silica nanoparticles. FT‐IR, SEM and TGA were applied to evaluate the loading of SC, self‐healing test was used to confirm the self‐healing capability of NC hydrogel. NC hydrogels were coated on the surfaces of Q235 steel, the exposure test results suggest that the corrosion protection of NC hydrogel improves with the loading of SC. Macro, micro morphologies prove that with the releasing of SC, a layer of adsorptive film was formed on the steel surface to prohibit the corrosion of carbon steel. Electrochemical results signify that NC (0.9 wt.% SC) hydrogel possesses the optimum corrosion resistance. The authors consider that as carrier, NC hydrogel can fulfill better corrosion inhibitive action of SC, meanwhile, effectively provide corrosion protection for carbon steel. [ABSTRACT FROM AUTHOR]

Piezocatalysis offers a means to transduce mechanical energy into chemical potential, harnessing physical force to drive redox reactions. Working in the solid state, we show here that piezoelectric BaTiO3 nanoparticles can transduce mechanical load into a flux of reactive radical species capable of initiating solid state free radical polymerization. Activation of a BaTiO3 powder by ball milling, striking with a hammer, or repeated compressive loading generates highly reactive hydroxyl radicals (⋅OH), which readily initiate radical chain growth and crosslinking of solid acrylamide, acrylate, methacrylate and styrenic monomers. Control experiments indicate a critical role for chemisorbed water on the BaTiO3 nanoparticle surface, which is oxidized to ⋅OH via mechanoredox catalysis. The force‐induced production of radicals by compressing dry piezoelectric materials represents a promising new route to harness mechanical energy for solid state radical synthesis. [ABSTRACT FROM AUTHOR]

In this review, we provide a brief history, progress, and applications, and discuss the remaining challenges of photocontrolled reversible addition–fragmentation chain transfer (RAFT) polymerization (i.e., photoinduced electron/energy transfer-RAFT (PET-RAFT), photoiniferter, and photomediated cationic RAFT polymerization). Among these, visible-light-driven RAFT polymerization has attracted particular attention in recent years due to its benefits, including low energy consumption and the safe reaction procedure. Moreover, the incorporation of visible-light photocatalysis in the polymerization has conferred attractive features, such as spatiotemporal control and oxygen tolerance; however, a clear understanding of the reaction mechanism has not been completely provided. We also present recent research efforts to elucidate the polymerization mechanisms with the aid of quantum chemical calculations combined with experimental evidence. This review offers an insight into the better design of polymerization systems for desired applications and helps realize the full potential of photocontrolled RAFT polymerization in both academic- and industrial-scale applications. [ABSTRACT FROM AUTHOR]

Cross-linked siloxane/silsesquioxane-based elastomers were easily prepared in 15 min via the anionic ring-opening polymerization of cyclotetrasiloxane (D4) and a polyhedral oligomeric silsesquioxane, using K2CO3 as a catalytic base in dimethylformamide at 70 °C. The resulting silicone elastomers have high mechanical strength, good thermal stability, and good superhydrophobic properties. [ABSTRACT FROM AUTHOR]

The synthesis and characteristics of composites based on bisphenol A diacrylate with the addition of 2-ethylhexyl acrylate, butyl acrylate, or methyl methacrylate were carried out. Benzethonium chloride and zinc oxide were used as special additives in amounts of 1, 2, and 5 % by weight of monomers. These are compounds that exhibit antimicrobial properties. The composites were produced by the UV polymerization method with the addition of Irgacure 651 as a photoinitiator. Aging and swelling tests were carried out in water, solutions of hydrochloric acid and sodium hydroxide, and acetone. To confirm the changes in the structure of the composites, ATR/FT-IR spectra were performed before and after the degradation process. The hardness of the composites was also tested. The antimicrobial properties against Escherichia coli, Staphylococcus aureus, Aspergillus niger, and Candida albicans were checked. The conducted study also showed the significant changes in the Cerrena unicolor fungus secretome caused by the presence of the composites. [ABSTRACT FROM AUTHOR]

[Display omitted] • Eugenol is anchored on the surface via cation-π interaction for the first time. • The polymer synthesis only requires simple one-step free radical polymerization. • Significant environmental friendliness compared to traditional coatings. Traditional self-polishing antifouling coatings kill surface organisms by releasing toxic substances, which are damaging to the ecosystem. As a natural antimicrobial substance, eugenol is environmentally friendly and has been proven by different research teams to be effective in enhancing the anti-fouling effect of coatings in the real sea. While in these previous research works, the eugenol was released directly into the seawater thus cannot further serve as surface antifouling effect, leading to a limited antifouling effect of the coating. In this work, the quaternary ammonium component was introduced into the butyl ester-based resin - poly (eugenol methacrylate - acryloyloxyethyltrimethyl ammonium chloride - hexafluorobutyl methacrylate - methyl methacrylate - butyl methacrylate - ethylene glycol methyl ether acrylate) (EMQFP) coating for the first time by simple one-step free radical polymerization method. On the one hand, the eugenol produced by hydrolysis is anchored to the quaternary ammonium on the coating surface for a period of time due to the cationic-π interaction, instead of being released into seawater immediately after hydrolysis, thus increasing the utilization rate of eugenol; on the other hand, the negatively charged carboxylate groups generated after hydrolysis in the coating are mutually attracted to quaternary ammonium through electrostatic effect, so the resin chain segment conformation on the coating surface adjusted to produce zwitterionic-like structure, and the hydration of zwitterionic inhibits primary fouling adhesion. [ABSTRACT FROM AUTHOR]

Anionic polymerization is an established process for the synthesis of well‐defined block copolymers. Due to the high reaction rates, a good knowledge of the process and its heat generation is of great importance for safe reaction control. This is to be achieved by the development and validation of a combined kinetic and heat transport model. The validation of the combined model was based on the experimentally anionic homo‐polymerization of styrene that was expanded for the block co‐polymerization of styrene and isoprene carried out in cyclohexane in batch reactors. [ABSTRACT FROM AUTHOR]

Polymer fouling is a major problem for the operation of continuous reactors. Therefore, it is important to understand and quantitatively describe the mechanisms leading to formation of fouling deposits. In this work, a CFD model for the radical polymerization of N‐vinylpyrrolidone is presented, where the reaction kinetics, a viscosity model, and a transport model for polymer moments are determined from independent experiments. The model is compared to experimental obtained residence time distributions in capillary reactors over a wide range of concentrations. Model predictions are in good agreement with experimental findings. [ABSTRACT FROM AUTHOR]

Hydrogels incorporating different reactive groups are important platforms for the fabrication of functional materials through the conjugation of diverse molecules. In this study, a dual-reactive hydrogel system was designed utilizing aldehyde and azide groups containing methacrylate monomers. Hydrogels were obtained in the presence of a dimethacrylate crosslinker with a combination of hydrophilic PEG-based monomers via free-radical polymerization. The azide and aldehyde sites of the hydrogel network are reactive towards alkyne and amine functional groups, respectively. The advantage of the different reactivities of these functional groups was demonstrated through the attachment of two different dye molecules onto the hydrogel platform via the "Huisgen click" and "Schiff base" reactions to obtain a sensing platform for various applications, such as indicating change in pH of the environment. [ABSTRACT FROM AUTHOR]

We report herein the cationic polymerization of isobutylene (IB) under mild conditions is realized with a new binary initiation system generated by simply mixing a Lewis super acid Al(C6F5)3 and a substituted phenol (RPhOH). Polymers with medium and/or high molecular weights (Mw=4.9×104−27.7×104 g·mol−1) can be obtained in toluene and temperatures from −20 °C to 0 °C. NMR spectrum analysis and DFT simulation reveals the in situ generated acidic coordinating complex Al(C6F5)3·RPhOH is the initiating active species, which further transformed into the ion-pair [Al(C6F5)3ORPh]−[PIB]+ of the active intermediates upon growing IB monomers where the counter anion [Al(C6F5)3ROPh]− coordinates to the macrocation via the phenoxy oxygen. The catalyst performances are the concert effects of the steric bulkiness and electronics of the counter anion on the coordinating strength to the macrocation, which is significant to the stability of the active species. [ABSTRACT FROM AUTHOR]

To address the increasing demand for biobased materials, lignin-derived ferulic acid (FA) is a promising candidate. In this study, an FA-derived styrene-like monomer, referred to as 2-methoxy-4-vinylphenol (MVP), was used as the platform to prepare functional monomers for radical polymerizations. Hydrophobic biobased monomers derived from MVP were polymerized via solution and emulsion polymerization resulting in homo- and copolymers with a wide range of thermal properties, thus showcasing their potential in thermoplastic applications. Moreover, divinylbenzene (DVB)-like monomers were prepared from MVP by varying the aliphatic chain length between the MVP units. These biobased monomers were thermally crosslinked with thiol-bearing reagents to produce thermosets with different crosslinking densities in order to demonstrate their thermosetting applications. The results of this study expand the scope of MVP-derived monomers that can be used in free-radical polymerizations toward the preparation of new biobased and functional materials from lignin. [ABSTRACT FROM AUTHOR]

Styrene-based thermoplastic elastomers (TPEs) demonstrate excellent overall performance and account for the largest industrial output. The traditional methods of preparation styrene-based thermoplastic elastomers mainly focused on anionic polymerization, and strict equipment conditions were required. In recent years, controlled/living radical polymerization (CRP) has developed rapidly, enabling the synthesis of polymers with various complex topologies while controlling their molecular weight. Herein, a series of core crosslinked star-shaped poly(styrene-b-isoprene-b-styrene)s (SISs) was synthesized for the first time via reversible addition–fragmentation chain transfer (RAFT) polymerization. Meanwhile, linear triblock SISs with a similar molecular weight were synthesized as a control. We achieved not only the controlled/living radical polymerization of isoprene but also investigated the factors influencing the star-forming process. By testing the mechanical and thermal properties and characterizing the microscopic fractional phase structure, we found that both the linear and star-shaped SISs possessed good tensile properties and a certain phase separation structure, demonstrating the characteristics of thermoplastic elastomers. [ABSTRACT FROM AUTHOR]

Cationic polyacrylamide (CPAM) is a commonly used flocculant for water treatment. The main factors affecting its flocculation performance are cationic degree and intrinsic viscosity. This study was to improve the intrinsic viscosity and cationic degree of CPAM, sodium polyacrylate was selected as the template (T), and dimethyldiallylammonium chloride (DMD) and acrylamide (AM) were used as monomers to prepare a Novel cationic polyacrylamide (TPDA) with ultraviolet (UV)-initiated template polymerization. First, single-factor tests were conducted to screen the factors that had significant effects on TPDA intrinsic viscosity, and then response surface methodology (RSM) tests were conducted using the selected factors to obtain the optimal polymerization conditions. The results showed that the addition of template increased the cationic degree of TPDA, and decreased its intrinsic viscosity. there were three factors that significantly affected TPDA intrinsic viscosity, and the order of significance was the initiator concentration, monomer mass fraction and pH. A model that could guide the TPDA polymerization was obtained by RSM tests. The results of model optimization showed that the optimal conditions for TPDA polymerization were as follows: the monomer mass fraction, pH value, concentration of photoinitiator (V-50), mass fraction of urea and n(T):n(DMD):n(AM) in the polymerization solution were 27.1%, 7.2, 0.47‰, 0.3%, 3:3:7, respectively, and the ultraviolet irradiation time of 70 min, and the intrinsic viscosity of the obtained TPDA was.10.98 dL/g. [ABSTRACT FROM AUTHOR]

A scheme for manufacturing heavy-duty rail grinding wheels with silicone-modified phenolic resin (SMPR) as a binder in the field of rail grinding is presented to improve the performance of grinding wheels. To optimize the heat resistance and mechanical performance of rail grinding wheels, an SMPR for industrial production of rail grinding wheels was prepared in a two-step reaction using methyl-trimethoxy-silane (MTMS) as the organosilicon modifier by guiding the occurrence of the transesterification and addition polymerization reactions. The effect of MTMS concentration on the performance of silicone-modified phenolic resin for application in rail grinding wheels was investigated. The molecular structure, thermal stability, bending strength, and impact strength values of the SMPR were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and mechanical property testing, and the effect of MTMS content on the resin properties was investigated. The results indicated that MTMS successfully improved the performance of the phenolic resin. The thermogravimetric weight loss temperature of the SMPR modified by MTMS with 40% phenol mass at 30% weight loss is 66% higher than that of common phenolic resin (UMPR), exhibiting the best thermal stability; in addition, its bending strength and impact strength were enhanced by approximately 14% and 6%, respectively, compared with those of common UMPR. This study utilized an innovative Bronsted acid as a catalyst and simplified several intermediate reactions in the conventional silicone-modified phenolic resin technology. This new investigation of the synthesis process decreases the manufacturing cost of the SMPR, liberates it from the restrictions of grinding applications, and enables the SMPR to maximize its performance in the rail grinding industry. This study serves as a reference for future work on resin binders for grinding wheels and the development of rail grinding wheel manufacturing technology. [ABSTRACT FROM AUTHOR]

Dithiocarbonate‐based non‐hygroscopic polymers with a glass transition temperature (Tg) and polydispersity index (PDI) of ≈4 °C and 1, respectively, are synthesized through living cationic ring‐opening polymerization. These liquid‐state polymers are characterized by monodispersity based on the low Tg and PDI, rendering remarkable miscibility with the perovskite precursors without aggregation. Accordingly, these polymers are added to perovskite solar cells (PSCs) to enhance their power conversion efficiency (PCE). The PCE of reference PSCs increases from 19.70% to 23.52% after direct addition of the synthesized polymer. This efficiency improvement is attributed to the considerable increases in short‐circuit current density (JSC) and fill factor (FF), resulting from the augmented size and defect passivation of perovskite crystals induced by added polymers. In fact, the PCE and JSC of the devices measured in the laboratory and the certification center are the highest among the reported polymer‐added PSCs, thanks to the great miscibility of the new polymers leading to the large amount addition which enables more thorough passivation among the grain boundaries. The improvement in open‐circuit voltage falls short as compared to that in JSC and FF, ascribed to the relatively moderate interaction strength between perovskite materials and dithiocarbonate groups. [ABSTRACT FROM AUTHOR]

Waterborne polyurethane are more eco-friendly materials due to lower volatile organic compounds (VOCs, mainly isocyanates) content than the alternative materials. However, these rich hydrophilic groups polymers have not yet reached good mechanical properties, durability and hydrophobicity behaviors. Therefore, hydrophobic waterborne polyurethane has become a research hotspot, attracting significant attention. In this work, firstly, a novel fluorine-containing polyether P(FPO/THF) was synthesized by cationic ring-opening polymerization of 2-(2,2,3,3-tetrafluoro-propoxymethyl)-oxirane (FPO) and tetrahydrofuran (THF). Secondly, fluorinated polymer P(FPO/THF), isophorone diisocyanate (IPDI) and hydroxy-terminated polyhedral oligomeric silsesquioxane (POSS-(OH)8) were used to prepare a new fluorinated waterborne polyurethane (FWPU). Hydroxy-terminated POSS-(OH)8 was used as a cross-linking agent, while dimethylolpropionic acid (DMPA) and triethylamine (TEA) were used as a catalyst. Four kinds of waterborne polyurethanes (FWPU0, FWPU1, FWPU3, FWPU5) were obtained by adding different contents of POSS-(OH)8 (0%, 1%, 3%, 5%). The structures of the monomers and polymers were verified by 1H NMR and FT-IR, and the thermal stabilities of various waterborne polyurethanes were analyzed by thermogravimetric analyzer (TGA) and differential scanning calorimetry (DSC). As the results, the thermal analysis showed that the FWPU performed the good thermal stability and the glass transition temperature could reach at about −50 °C. The FWPU1 film exhibited that the elongation at break was 594.4 ± 3.6% and the tensile strength at break was 13.4 ± 0.7 MPa, elucidating that the FWPU1 film developed the excellent mechanical properties relative to the alternative FWPUs. Further, the FWPU5 film performed the promising properties, including the higher surface roughness of FWPU5 film (8.41 nm) obtained by the atomic force microscope (AFM) analysis, and the higher value of water contact angle (WCA) at 104.3 ± 2.7°. Those results illustrated that the novel POSS-based waterborne polyurethane FWPU containing a fluorine element could develop the excellent hydrophobicity and mechanical properties. [ABSTRACT FROM AUTHOR]

Functional copolymers of 1-vinyl-1,2,4-triazole (VT) and N-vinylcarbazole (VK) were synthesized using a free-radical polymerization. The content of hole-conducting N-vinylcarbazole units was found to be 9, 16, and 37 mol. %. Fourier transform infrared spectroscopy, 1H-NMR spectroscopy, gel permeation chromatography, thermogravimetric analysis, and differential scanning were applied to characterize the poly(VT–co–VK). Based on a polymer ligand, metal−polymer complexes with Tb3⁺ ions were obtained in a polymethyl methacrylate matrix, and their luminescent properties were studied. The maximum photoluminescence of the complex can be achieved when using 16 mol. % of N-vinylcarbazole units. This is because two photoprocesses (excimer formation and excitation energy transfer) occur simultaneously and competitively. [ABSTRACT FROM AUTHOR]

Free radical (co)polymerization (FRP/FRcP) of multivinyl monomers (MVMs) has emerged as a powerful strategy for the synthesis of chemically and topologically complex polymers due to its unique reaction kinetics, which enables the preparation of polymers with multiple functional groups and novel macromolecular structures. However, conventional FRP/FRcP of MVMs inevitably leads to insoluble crosslinked materials. Therefore, the development of advanced strategies for the controlled polymerization of MVMs is essential for the preparation of chemically and topologically complex polymers. In this review, we introduce the gelation mechanism of conventional FRP of MVMs and present the strategies of controlled polymerization of MVMs for the preparation of chemically and topologically complex polymers. We also discuss polymers with unique topologies synthesized by controlled polymerization of MVMs, such as crosslinked networks, (hyper)branched, star, cyclic, and single-chain cyclized/knotted structures. Finally, biomedical applications of various advanced polymeric materials prepared by controlled polymerization of MVMs are highlighted and the challenges is this field are discussed. [ABSTRACT FROM AUTHOR]

Complex pollutants are discharging and accumulating in rivers and oceans, requiring a coupled strategy to resolve pollutants efficiently. A novel method is proposed to treat multiple pollutants with C,N co-doped TiO2 hollow nanofibers coated stainless steel meshes which can realize efficient oil/water separation and visible light-drove dyes photodegradation. The poly(divinylbenzene-co-vinylbenzene chloride), P(DVB-co-VBC), nanofibers are generated by precipitate cationic polymerization on the mesh framework, following with quaternization by triethylamine for N doping. Then, TiO2 is coated on the polymeric nanofibers via in-situ sol–gel process of tetrabutyl titanate. The functional mesh coated with C,N co-doped TiO2 hollow nanofibers is obtained after calcination under nitrogen atmosphere. The resultant mesh demonstrates superhydrophilic/underwater superoleophobic property which is promising in oil/water separation. More importantly, the C,N co-doped TiO2 hollow nanofibers endow the mesh with high photodegradation ability to dyes under visible light. This work draws an affordable but high-performance multifunctional mesh for potential applications in wastewater treatment. [ABSTRACT FROM AUTHOR]

Mechanical robust hydrogels are ideal for applications in energy, environment, biomedicine, and structural engineering materials fields. However, high strength and high toughness are usually in conflict with each other, and simultaneously achieving both of them within a hydrogel has been challenging. Herein an organic‐inorganic synergistic toughening strategy is reported via in‐situ inorganic ionic polymerization of calcium phosphate oligomers within polymer composite networks composed of polyvinyl alcohol chains and aramid nanofibers. The composite hydrogels are provided with a prestress‐induced hierarchically fibrous structure through the assembly, which resulted in the mechanical strength and toughness up to 24.15 ± 1.12 MPa and 15.68 ± 1.78 MJ m−3, respectively, surpassing most toughened hydrogels. Through lamination and crosslinking, bulk hydrogels with controllable mechanical anisotropy and significant energy absorption/dissipation ability are produced. Moreover, the recycling and regeneration of the hydrogels are easily realized owing to the physically crosslinked network and acid‐induced dissolution of the inorganic units of the hydrogels, which lays a foundation for the sustainable large‐scale production and application of the hydrogels. This study provides an alternative approach for the development of mechanical robust and recyclable nanocomposite hydrogels for various applications including soft body armor, flexible electronics, soft robotics, etc. [ABSTRACT FROM AUTHOR]

This study scrutinized the use of monomer hydroxyethyl methacrylate, 2-carboxyethyl acrylate, initiator ammonium persulfate and cross-linker N′N′-methylene bisacrylamide to form polymeric composites by employing free radical polymerization of poorly water-soluble drug Letrozole (LTE). Letrozole is an aromatase inhibitor used in the treatment of breast cancer. Swelling index %, entrapment efficiency and solubility studies of developed formulations (LTE1-LTE9) were evaluated. Swelling studies indicated an increased swelling index at pH 7.4. The solubility of developed formulation was enhanced as compared to pure drug and β-cyclodextrin-Letrozole complex. Characterization of developed polymeric composites was performed by FTIR, DSC/TGA, SEM, XRD and zeta size. FTIR studies confirmed the encapsulation of Letrozole within polymeric composites. DSC/TGA indicated a thermally stable formulation. Surface morphology was assessed by SEM. XRD confirmed the amorphous formulation. The release study followed the Korsmeyer–Peppas model. In toxicity studies, clinical observations, hematological parameters and histopathological studies showed that developed polymeric composites were not toxic. Conclusively, our findings suggest that developed polymeric composites were safe and increased the solubility of poorly water-soluble drug and can be used as an effective platform for other hydrophobic drugs. [ABSTRACT FROM AUTHOR]

A vinyl ether containing a five-membered cyclic carbonate group, 2-(2-vinyloxyethoxy)ethyl carbonate (VEECN), was synthesized by adding CO2 to 2-(2-vinyloxyethoxy)ethyl glycidyl ether, which is a vinyl ether containing an epoxy group. Cationic polymerization of VEECN was performed in nitromethane at − 30 °C with boron trifluoride etherate. The resulting poly(VEECN) exhibited a number-average molecular weight of ~ 3500 g/mol and a molecular weight distribution of ~ 1.40. Poly[2-(2-vinyloxyethoxy)ethyl hydroxyurethane]s [poly(VEEHU)-C2 to -C5] were synthesized by reacting the cyclic carbonates in the side chains of the obtained poly(VEECN) with four alkanolamines with different methylene numbers (2–5) to form hydroxyurethane groups. The reaction ratios were adjusted to approximately 50%, 75%, and 100%, and the thermal responses and properties of poly(VEEHU)-C2 to -C5 were investigated. When the urethanization ratio was ~ 50%, the cloud points (Tcp) of 1% w/v poly(VEEHU)-C3 to -C5 aqueous solutions were observed at 46, 27, and 8 °C, respectively, with the temperature decreasing with increasing methylene number. Conversely, the poly(VEEHU)-C2 aqueous solution did not exhibit a Tcp at ≤ 95 °C. The glass transition temperatures of the polymers were − 32 °C for poly(VEECN) and − 28, − 32, − 33, and − 35 °C for poly(VEEHU)-C2 to -C5, respectively. Additionally, the thermal decomposition temperatures of the polymers were 279 °C for poly(VEECN) and 253–262 °C for poly(VEEHU)-C2 to -C5, indicating that poly(VEEHU) were flexible polymers at room temperature with relatively high thermal stabilities. [ABSTRACT FROM AUTHOR]

A solid slide‐ring supramolecular elastomer is constructed by free‐radical polymerization of 2‐(2‐methoxyethoxy)ethyl methacrylate, acrylate‐modified perylene diimides (PDI), and the polyrotaxane (PR) cross‐linker. Benefiting from reciprocating shuttle function of slide‐ring PR formed by acrylate‐modified α‐cyclodextrin threading on polyethylene glycol, the resultant supramolecular elastomer not only presents excellent tensile property, toughness, and fatigue resistance up to 100 cycles, but also gives reversible mechano‐induced fluorescence changes from red to orange luminescence due to a reversible conversion of PDI dimer to monomer upon mechanical stretching. After the dye molecule Nile blue is added as a fluorescent acceptor, the supramolecular elastomer exhibits highly reversible mechano‐induced regulation of energy transfer and can perform five cycles without optical fatigue. This bifunctional mechanochromic slide‐ring supramolecular elastomer, which not only possesses mechanically reversible motion of the slide‐ring cross‐linkers but also has the mechanochromic response of fluorophore, endows the intrinsic superiority of slide‐ring into fatigue resistant mechanoresponsive strain sensing materials. [ABSTRACT FROM AUTHOR]

To predict the polymer properties produced by free‐radical polymerization of N‐vinylpyrrolidone (NVP) in aqueous solution a detailed kinetic model has been developed. The kinetic model allows to calculate the chain length distribution, the number of branching points, and the number of terminal double bonds (TDB). The latter is accounted for since TDBs are a precondition for branching. While monomer conversion can be predicted sufficiently using independently determined rate constants for propagation and termination, here the predictions of structural properties by a newly developed extended kinetic model to experimental findings are compared. Polymer produced in a continuous stirred tank reactor is analyzed by gel permeation chromatography (GPC), field flow fractionation (FFF), and high‐pressure liquid chromatography (HPLC). [ABSTRACT FROM AUTHOR]

Organic peroxides, due to temperature manipulation failure and/or manner disturbances, had been probable to lead to the prevalence of runaway phenomena, even fire, and explosion. Cumene hydroperoxide (CHP), is a traditional liquid organic peroxide for industrial purposes and is applied as a free radical initiator for polymerization reactions in the petrochemical industry. Its utilization in the industrial processes had certain potential safety hazards. In this work, linearly ramped thermal decomposition in CHP was performed using differential scanning calorimetry under a nitrogen atmosphere. Kinetic analysis is made using data from the ramped measurements with two integral strategies (Flynn-Wall-Ozawa and Kissinger-Akahira-Sunose). The gaseous products of thermal decomposition in CHP are investigated via thermal gravimetric evaluation coupled with Fourier transform infrared spectroscopy and gas chromatography/mass spectrometry. Combined with the experimental results, the possible decomposition path of CHP is discussed. This makes up the gap of unclear decomposition mechanism of CHP in inert atmosphere, and has important reference significance for its industrial production and application. [Display omitted] [ABSTRACT FROM AUTHOR]

Photopolymerization offers a unique opportunity to convert liquid monomers to polymers using light as the activation source. Recently, major efforts have been devoted to developing visible light photo-initiating systems, and the search for new dyes that can be incorporated into photocurable resins and polymerize a resin within a few seconds is still ongoing. With the aim of exploring a maximum of structures to reach this goal, quinoxaline has been identified to be a promising scaffold for the design of UV-centered and visible light photo-initiating systems. In this review, an overview of the different quinoxaline-based dyes will be given. In order to evidence the interest in these structures, comparisons with reference systems will be given. [ABSTRACT FROM AUTHOR]

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A statistical modeling procedure is established for carbocation polymerization with the characteristics of living with chain transfer. A single state model is suggested for cases of narrow molecular weight distribution, whereas a multi‐state model is claimed for cases of broad distribution. In the multi‐state case, it is demonstrated how the overall kinetics can be derived using the expectations and variances of the kinetic parameters rather than those of individual states, thereby simplifying the modeling step. Although the expectation and variance do not follow the relationship of the Arrhenius equation, a procedure is given for how to account for temperature dependence. The proposed statistical method minimizes the number of parameters to identify and therefore is expected to help establish a model with fewer experiments. The whole procedure is demonstrated through an experimental study of isobutylene polymerization. [ABSTRACT FROM AUTHOR]

This contribution reports the efficient conversion of γ‐valerolactone and its derivatives, abundant but unexplored renewable feedstocks, into sustainable and degradable polythioesters via the establishment of the first isomerization‐driven ring‐opening polymerizations (IROPs) of corresponding thionolactone intermediates. The key to this success relies on the development of a new simple and robust [Et3O]+[B(C6F5)4]− cationic initiator which possesses high activity, exclusive selectivity, living nature, and broad scope of thionolactones. A complete inversion of configuration during IROP of enantiopure γ‐thionovalerolactone is also disclosed, affording isotactic semicrystalline polythioesters (Tm=87.0 °C) with mechanical property compared well to the representative commodity polyolefins. The formation of a highly crystalline supramolecular stereocomplex with enhanced thermal property (Tm=117.6 °C) has also been revealed. [ABSTRACT FROM AUTHOR]

Poor electronic and ionic conductivity of electrode materials at low temperatures of −20 °C and below has significantly impeded development of batteries for cold conditions. However, for the first time, layer‐structured metallic vanadium diselenide (1T‐VSe2) is reported as a cathode material for low‐temperature Mg2+/Li+ hybrid batteries. A high electronic conductivity and fast ion diffusion kinetics for 1T‐VSe2 are demonstrated at selected temperatures, and a very safe 1T‐VSe2/Mg battery for operation at temperatures to −40 °C. The battery exhibits 97% capacity retention over 500 cycles, which is better performance than reported Mg‐based batteries. The Jahn–Teller effect in compressed configuration is initiated in 1T‐VSe2 with the change of electronic state occurring on electrochemical intercalation of alkali metal ions. Using combined experiment and theory via operando synchrotron X‐ray diffraction, ex situ X‐ray absorption spectroscopy and DFT computation, it is confirmed that the weak Jahn–Teller distortion contributes significantly to fast‐overall kinetics, structural stability, and high electronic conductivity of the electrode. Understanding at an atomic level of the mechanism is demonstrated, that provides valuable guidance in designing high‐performance electrode materials for low‐temperature batteries. [ABSTRACT FROM AUTHOR]