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Porous frameworks with controlled pore structure and tunable aperture are greatly demanded. However, precise synthesis of this kind of materials is a formidable challenge. Herein, we report the fabrication of two‐dimensional (2D) supramolecular polymer frameworks using a precisely synthesized rod‐like helical polyisocyanide as link. Four three‐arm star‐shaped polyisocyanides with the degree of the polymerization of 10, 20, 30 and 40, and having 2‐ureido‐4[1H]‐pyrimidinone (UPy) terminals were synthesized. 2D‐Crystalline polymer frameworks with apertures of 5.3, 10.1, 13.9, and 19.1 nm were respectively obtained through intermolecular hydrogen bonding interaction between the terminal Upy units. The pore aperture is dependent on the length of polyisocyanide backbone. Thus, well‐defined supramolecular polymer frameworks with controlled and uniform hexagonal pores were obtained, as proved by small‐angle X‐ray scattering (synchrotron radiation facility), atomic force microscopy, and Brunauer–Emmett–Teller analyses. The frameworks with uniform large pore aperture were used to purify nanomaterials and immobilize biomacromolecules. For instance, the membranes of the polymer frameworks could size‐fractionation of silver nanoparticles into uniform nanoparticles with very low dispersity. The frameworks with large aperture facilitated the inclusion of myoglobin and enhanced the stability and catalytic activity. [ABSTRACT FROM AUTHOR]

The development of cleaner, more environmentally friendly processes in polymerization technology is crucial due to the prevalent use of volatile organic solvents (VOCs), which are harmful and toxic. Future regulations are likely to limit or ban VOCs. This review explores the use of supercritical solvents, specifically supercritical CO2 (scCO2), in polymerization processes. The study focuses on reversible addition‐fragmentation chain‐transfer (RAFT) induced homo‐polymerization of various monomers using specific chain transfer agents (CTAs) in scCO2. RAFT polymerization, a reversible deactivation radical polymerization (RDRP) polymerization, relies heavily on the choice of CTA, which significantly influences the dispersity and molar mass of the resulting polymers. Stabilizers are also crucial in controlling product specifications for polymerizations in supercritical CO2, except for fluor‐based polymers, although they must be removed and preferably recycled to ensure product purity and sustainability. The review notes that achieving high molar mass through RAFT polymerization in scCO2 is challenging due to solubility limits, which lead to polymer precipitation. Despite this, RAFT polymerization in scCO2 shows promise for sustainable, circular production of low molar mass polymers, although these cannot yet be fully considered green products. [ABSTRACT FROM AUTHOR]

Controlled radical copolymerizations present attractive avenues to obtain polymers with complicated compositions and sequences. In this work, we report the development of a visible‐light‐driven organocatalyzed controlled copolymerization of fluoroalkenes and acyclic N‐vinylamides for the first time. The approach enables the on‐demand synthesis of a broad scope of amide‐functionalized main‐chain fluoropolymers via novel fluorinated thiocarbamates, facilitating regulations over chemical compositions and alternating fractions by rationally selecting comonomer pairs and ratios. This method allows temporally controlled chain‐growth by external light, and maintains high chain‐end fidelity that promotes facile preparation of block sequences. Notably, the obtained F/N hybrid polymers, upon hydrolysis, afford free amino‐substituted fluoropolymers versatile for post modifications toward various functionalities (e.g. amide, sulfonamide, carbamide, thiocarbamide). We further demonstrate the in situ formation of polymer networks with desirable properties as protective layers on lithium metal anodes, presenting a promising avenue for advancing lithium metal batteries. [ABSTRACT FROM AUTHOR]

New and simple ligand design strategies for the preparation of versatile metal-based catalysts capable of operating under greener and eco-friendly conditions in several industrially attractive processes are in high demand for society development. We present the first nucleophilic addition of an organolithium to ketenimines which incorporates a stereogenic centre in an N-donor atom to prepare new enantiopure NNN-donor scorpionates. We have also verified its potential utility as a valuable scaffold for chirality induction through the preparation of inexpensive, non-toxic and asymmetric zinc complexes. The pro-ligands and the corresponding zinc-based complexes have been characterized by X-ray diffraction studies. DFT studies were carried out to rationalize the different complexation abilities of these pro-ligands. These complexes have proved to act as highly efficient catalysts for a variety of sustainable bioresourced processes that are industrially attractive, with a wide substrate scope. Thus, complex 7 behaves as a highly efficient initiator for the well-behaved living ring-opening polymerization (ROP) of rac-lactide under very mild conditions. The PLA materials produced exhibited enhanced levels of isoselectivity, comparable to the highest value reported so far for zinc-based catalysts (Pi = 0.88). In addition, the combination of 7 with onium halide salts functioned as a very active and selective catalyst for CO2 fixation into five-membered cyclic carbonates through the cycloaddition of CO2 into epoxides under very mild and solvent-free conditions, reaching very good to excellent conversions (TOF = 227 h−1). Furthermore, this bicomponent system exhibits a broad substrate scope and functional group tolerance, including mono- and di-substituted epoxides, as well as the very challenging bio-renewable tri-substituted terpene-derived cis/trans-limonene oxide, whose reaction proceeds with high stereoselectivity. Finally, complex 7 also achieved high activity and selectivity as a one-component initiator for the synthesis of poly(cyclohexene carbonate)s via ring-opening copolymerization (ROCOP) of cyclohexene oxide and CO2 under very soft conditions, affording materials with narrow dispersity values. [ABSTRACT FROM AUTHOR]

The precise synthesis of chiral polymers remains a significant challenge in polymer chemistry, particularly for applications in advanced biomedical and electronic materials. The development of degradable polymers is important for eco‐friendly and advanced materials. Here, we introduce a stereo‐controlled degradable polymer via cascade enyne metathesis polymerization and enantioselective acetal synthesis through Pd‐catalyzed asymmetric hydroamination. This approach allows for the creation of chiral acetal‐based polymers with controlled stereochemistry and degradability, highlighting their potential for use in drug delivery and electronic applications. This concept article reviews the background, development, and potential applications of these stereo‐controlled degradable polymers. [ABSTRACT FROM AUTHOR]

Intracellular polymerization in living cells motivated chemists to generate polymeric structures with a multitude of possibilities to interact with biomacromolecules. However, out-of-control of the intracellular chemical reactions would be an obstacle restricting its application, providing the toxicity of non-targeted cells. Here, we reported intracellular thioesterase-mediated polymerization for selectively occurring polymerization using disulfide bonds in cancer cells. The acetylated monomers did not form disulfide bonds even under an oxidative environment, but they could polymerize into the polymeric structure after cleavage of acetyl groups only when encountered activity of thioesterase enzyme. Furthermore, acetylated monomers could be self-assembled with doxorubicin, providing doxorubicin loaded micelles for efficient intracellular delivery of drug and monomers. Since thioesterase enzymes were overexpressed in cancer cells specifically, the micelles were disrupted under activity of the enzyme and the polymerization could occur selectively in the cancer mitochondria. The resulting polymeric structures disrupted the mitochondrial membrane, thus activating the cellular death of cancer cells with high selectivity. This strategy selectively targets diverse cancer cells involving drug-resistant cells over normal cells. Moreover, the mitochondria targeting strategy overcomes the development of drug resistance even with repeated treatment. This approach provides a way for selective intracellular polymerization with desirable anticancer treatment. [Display omitted] • Thioesterase enzyme is overexpressed in cancer cells due to abnormal metabolism. • The acetylated thiol monomers can form disulfide bonds only under activity of thioesterase. • Thioesterase-meditated polymerization using disulfide bonds generates polymeric structures selectively in cancer cells. • The enzyme-meditated polymerization induces cancer cellular death without the development of drug-resistance. [ABSTRACT FROM AUTHOR]

The nanocomposites of ferroferric oxide (Fe3O4) with polyhydroxyurethane (PHU) were fabricated via a physical mixing approach. This process involved grafting poly(N‐vinyl pyrrolidone) (PVPy) chains onto the surfaces of Fe3O4 nanoparticles via surface‐initiated living radical polymerization. The PVPy‐grafted Fe3O4 nanoparticles were directly incorporated into the precursors of PHUs [i.e., bis(cyclic carbonate) and a trifunctional amine] and the mixtures were cured at high temperatures to form organic–inorganic composites. This method ensured that Fe3O4 nanoparticles were finely dispersed within the PHU matrix through the strong intermolecular hydrogen bonding between PVPy and PHU. Compared to plain PHU network, the nanocomposites had enhanced thermomechanical properties, including higher glass transition temperatures (Tg's) and improved tensile mechanical properties. The inclusion of Fe3O4 nanoparticles also enhanced the shape memory properties of the PHU networks, improving shape recovery rates, fixity of transient shapes, and recovery of the original shapes. In addition, the nanocomposites demonstrated paramagnetic and photothermal properties and the photothermal behavior enabled a non‐contact control of shape recovery. Highlights: Poly(N‐vinyl pyrrolidone)‐grafted Fe3O4 nanoparticles were synthesized.Nanocomposites of PHU with Fe3O4 were prepared via a physical blending approach.Incorporation of Fe3O4 resulted in improved thermomechanical properties.The nanocomposites had the photothermal properties. [ABSTRACT FROM AUTHOR]

Controlled radical polymerization (CRP) techniques enable the preparation of diverse, chemically tailored polymers with a variety of chain architectures. Separately, light‐mediated polymerization reactions offer a number of advantages over thermal polymerizations in terms of energy efficiency, sustainability, and versatility. Recent work has combined photopolymerization and CRP techniques to advance the synthesis of polymers with nonlinear architectures, including bottlebrush polymers, star polymers, hyperbranched polymers, and cyclic polymers. These photoCRP methods offer novel routes to nonlinear polymers using mild reaction conditions. In this review, we provide an overview of photoCRP techniques for the synthesis of nonlinear polymers. We start with a discussion of photoCRP applied to the synthesis of linear polymers and discuss the underlying reaction mechanisms. Then, we discuss photoCRP applied to the synthesis of bottlebrush, star, hyperbranched, cyclic, and surface‐initiated polymer brushes. For each case, we discuss the synthetic strategy and the unique properties and characteristics of the resulting polymers, and we provide a perspective on potential future directions for research. [ABSTRACT FROM AUTHOR]

A dual zwitterionic diblock copolymer (M100C100) consisting of poly(2‐(methacryloyloxy)ethyl phosphorylcholine) (PMPC, M) and poly(3‐((2‐(methacryloyloxy)ethyl) dimethylammonio) propionate) (PCBMA, C) is synthesized via reversible addition‐fragmentation chain transfer (RAFT) polymerization. A double hydrophilic diblock copolymer (M100S100) consist of PMPC and anionic poly(3‐sulfopropyl methacrylate potassium salt) (PMPS, S) is synthesized via RAFT. The degrees of polymerization of each block are 100. The charges of PMPC are neutralized intramolecularly. At neutral pH, the charges in PCBMA are also neutralized intramolecularly due to its carboxybetaine structure. Under acidic conditions, PCBMA exhibits polycation behavior as the pendant carboxy groups become protonated, forming cationic tertiary amine groups. PMPS shows permanent anionic nature independent of pH. Charge neutralized mixture of cationic M100C100 and anionic M100S100 in acidic aqueous solution forms water‐soluble polyion complex (PIC) micelle owing to electrostatic attractive interactions. The core is composed of the cationic PCBMA and anionic PMPS blocks, with the PMPC blocks serving as shells that covered the core surface, forming spherical core–shell PIC micelles. Above pH 4 the pendant carboxy groups in PCBMA undergo deprotonation, transitioning to a zwitterionic state, thereby eliminating the cationic charge in PCBMA. Therefore, above pH 4 the PIC micelles are dissociated due to the disappearance of the charge interactions. [ABSTRACT FROM AUTHOR]

While additive manufacturing based on multiphoton polymerization is currently considered to be a very promising technique for the fabrication of 3D micro‐ and nanostructures, long fabrication times are a major limitation of this approach. Parallelization of the fabrication process is an important technique to overcome this issue. The fabrication process is parallelized by imaging a 1920 × 1080 pixel spatial light modulator into an ultrasensitive triplet–triplet annihilation resist. However, proximity effects between close pixels generate uncontrolled polymerization and make the controlled fabrication of 3D structures difficult. This work models light propagation and chemical interactions in the system to predict fabricated structures with a view to precompensating plot data and improving 3D resolution by performing optical and chemical proximity correction. A simple model gives reasonable predictions of fabricated structures helping us fabricate fully 3D structures in parallel. [ABSTRACT FROM AUTHOR]

Amphiphilic block copolymers are characterized by the presence of distinct hydrophilic and hydrophobic regions, which are usually arranged in alternating blocks. This unique structure allows these copolymers to self‐assemble into well‐defined nanostructures that exhibit remarkable resistance to enzymatic hydrolysis, high biocompatibility and the ability to be customized with specific structures. These properties make them highly desirable in various applications. Self‐assembled amphiphilic polypeptoids are currently under development as a promising class of pharmaceutical agents. However, the utilization of these peptides as drug carriers for efficient delivery presents a number of challenges. These challenges include less‐than‐optimal loading efficacy and restricted biocompatibility. Herein, a series of stable amphiphilic block copolypeptoids (PNEG‐b‐PNBG and PNEG‐b‐PNHG) were designed and synthesized by controlled ring‐opening polymerization. PNEG chain segments provide hydrophilicity, while PNBG and PNHG chain segments provide hydrophobicity. The hydrophobic molecular chains aggregate in aqueous solutions, resulting in the formation of nano‐assemblies. The self‐assembled amphiphilic block polypeptoid copolymers were investigated. The morphologies of copolymers take the form of micelles from tens of nanometers to a few hundred nanometers. The properties of amphiphilic block copolypeptoids used as drug carriers were further investigated by conducting drug release and cytotoxicity tests. The results indicate that the cumulative release efficiency of self‐assembled polypeptoid copolymers can reach up to about 91%. And they have good biocompatibility and can be expected to be safe materials for efficient drug delivery. This work could provide a facile method for the preparation of amphiphilic block peptoid copolymers for biopharmaceutical applications. © 2024 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

The controlled polymerization of α‐methylene‐γ‐butyrolactone (MBL, a naturally occurring sesquiterpene lactone found in tulips) was performed by nitroxide mediated polymerization (NMP) using the alkoxyamine Dispolreg 007 as the initiating system at 80 °C in 50 wt% DMSO. Features of a reversible‐deactivation radical polymerization (RDRP) were observed with a linear growth of the macro‐radical with conversion and a relatively low dispersity (Ð ≤ 1.45). The P(MBL) homopolymer chain ends were mostly re‐activatable as the chain extensions with styrene (S) and glycidyl methacrylate (GMA) in DMSO were successful. Interestingly, the polymerization of MBL initiated by 2‐methyl‐2‐[N‐tert‐butyl‐N‐(1‐diethoxyphosphoryl‐2,2‐dimethylpropyl)‐aminoxy]‐N‐propionyloxysuccinimide (known as NHS‐BlocBuilder) under various experimental conditions did not produce well‐defined P(MBL), possibly due to an excessively high equilibrium constant. However, the bulk copolymerization of MBL with 10–21 mol% of β‐myrcene (Myr, another renewable monomer from the terpene family) initiated by NHS‐BlocBuilder at 100–110 °C led to all the features of a controlled system. The SG1 chain end fidelity of the resulting P(MBL‐co‐Myr) copolymer was confirmed via 31P NMR and by re‐initiating successfully the copolymer chains with a mixture of GMA and Myr monomers at 120 °C in DMSO. [ABSTRACT FROM AUTHOR]

The single‐unit monomer insertion (SUMI), derived from living/controlled polymerization, can be directly functionalized at the end or within the chain of polymers prepared by living/controlled polymerization, offering potential applications in the preparation of polymers with complex architectures. Many scenarios demand the simultaneous incorporation of monomers suitable for different polymerization methods into complex polymers. Therefore, it becomes imperative to utilize SUMI technologies with diverse mechanisms, especially those that are compatible with each other. Here, we reported the orthogonal SUMI technique, seamlessly combining radical and cationic SUMI approaches. Through the careful optimization of monomer and chain transfer agent pairs and adjustments to reaction conditions, we can efficiently execute both radical and cationic SUMI processes in one pot without mutual interference. The utilization of orthogonal SUMI pairs facilitates the integration of radical and cationic reversible addition‐fragmentation chain transfer (RAFT) polymerization in various configurations. This flexibility enables the synthesis of diblock, triblock, and star polymers that incorporate both cationically and radically polymerizable monomers. Moreover, we have successfully implemented a mixing mechanism of free radicals and cations in RAFT step‐growth polymerization, resulting in the creation of a side‐chain sequence‐controlled polymer brushes. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Nitrogen‐containing polymers have found a wide myriad of applications in materials science and other different areas, and have attracted much attention towards the development of new synthetic methods. Ring‐opening metathesis polymerization represents an area of great versatility and potential for the synthesis of highly functionalized polymers with low dispersity and control over molecular weight and architecture complexity. Expanding the scope of monomers through the incorporation of nitrogen atoms would further expand their utilities. In this work, a controlled synthesis of polymers with in‐chain enamide moiety through ring‐opening metathesis polymerization was developed by utilizing azetine derivatives as the monomers. Relatively short synthetic routes were designed and generated a panel of five monomers. The polymerization exhibited living characteristics, as linear relationship between molecular weights and degrees of polymerization and relatively narrow molar mass distributions were observed, which was further confirmed by successful diblock copolymers formation through sequential addition of two monomers. The resulting polymers that contain the enamide moiety within the backbone exhibited good stability and underwent facile degradation under acidic conditions. [ABSTRACT FROM AUTHOR]

Vapor‐phase propylene (C3H6) epoxidation kinetics with hydrogen peroxide (H2O2) strongly reflects the physical properties of Ti‐incorporated zeolite catalysts and the presence of spectating molecules ("solvent") near active sites even without a bulk liquid phase. Steady‐state turnover rates of C3H6 epoxidation and product selectivities vary by orders of magnitudes, depending on the zeolite silanol ((SiOH)x) density, pore topology (MFI, *BEA, FAU), and the quantity of condensed acetonitrile (CH3CN) molecules nearby active sites, under identical reaction mechanisms sharing activated H2O2 intermediates on Ti surfaces. Individual kinetic analyses for propylene oxide (PO) ring‐opening, homogeneous diol oxidative cleavage, and homogeneous aldehyde oxidation reveal that secondary reaction kinetics following C3H6 epoxidation responds more sensitively to the changes in zeolite physical properties and pore condensation with CH3CN. Thus, higher PO selectivities achieved in hydrophilic Ti‐MFI at steady‐state reflect the preferential stabilization of transition states for C3H6 epoxidation (a primary reaction) relative to PO ring‐opening and oxidative cleavage (secondary reactions) that solvation effects that reflect interactions among condensed CH3CN within pores and the extended pore structure. [ABSTRACT FROM AUTHOR]

Ring‐opening polymerization (ROP) offers a striking solution to solve problems encountered in step‐growth condensation polymerization, including precise control over molecular weight, molecular weight distribution, and topology. This has inspired our interest in ROP of cycloalkanes with an ultimate goal to rethink polyolefins, which clearly poses a number of challenges. Practicality of ROP of cycloalkanes is actually limited by their low polymerizability and elusive mechanisms which arise from significantly varied ring size and non‐polar C−C bonds in monomers. In this work, by using Lewis acid/Brønsted base/C(sp3)‐H initiator system previously developed in our laboratory, we focus on cyclobutanes and explore the positional and electronic effects of substituents on the ring, namely electron push‐pull effect, in promoting controlled polymerization to afford densely functionalized poly(cyclobutanes), as well as catalytic degradation of obtained polymers for upcycling. More importantly, experiments and DFT calculations unveil considerable population of Lewis‐acid‐induced thermostabilized 1,4‐zwitterions, which distinguish cyclobutanes from cyclopropanes and others. All these findings would shed light on catalytic synthesis and degradation of saturated all‐carbon main‐chain polymers, as well as small molecule transformations of cyclobutanes. [ABSTRACT FROM AUTHOR]

Vapor‐phase propylene (C3H6) epoxidation kinetics with hydrogen peroxide (H2O2) strongly reflects the physical properties of Ti‐incorporated zeolite catalysts and the presence of spectating molecules ("solvent") near active sites even without a bulk liquid phase. Steady‐state turnover rates of C3H6 epoxidation and product selectivities vary by orders of magnitudes, depending on the zeolite silanol ((SiOH)x) density, pore topology (MFI, *BEA, FAU), and the quantity of condensed acetonitrile (CH3CN) molecules nearby active sites, under identical reaction mechanisms sharing activated H2O2 intermediates on Ti surfaces. Individual kinetic analyses for propylene oxide (PO) ring‐opening, homogeneous diol oxidative cleavage, and homogeneous aldehyde oxidation reveal that secondary reaction kinetics following C3H6 epoxidation responds more sensitively to the changes in zeolite physical properties and pore condensation with CH3CN. Thus, higher PO selectivities achieved in hydrophilic Ti‐MFI at steady‐state reflect the preferential stabilization of transition states for C3H6 epoxidation (a primary reaction) relative to PO ring‐opening and oxidative cleavage (secondary reactions) that solvation effects that reflect interactions among condensed CH3CN within pores and the extended pore structure. [ABSTRACT FROM AUTHOR]

Polymer materials suffer mechano-oxidative deterioration or degradation in the presence of molecular oxygen and mechanical forces. In contrast, aerobic biological activities combined with mechanical stimulus promote tissue regeneration and repair in various organs. A synthetic approach in which molecular oxygen and mechanical energy synergistically initiate polymerization will afford similar robustness in polymeric materials. Herein, aerobic mechanochemical reversible-deactivation radical polymerization was developed by the design of an organic mechano-labile initiator which converts oxygen into activators in response to ball milling, enabling the reaction to proceed in the air with low-energy input, operative simplicity, and the avoidance of potentially harmful organic solvents. In addition, this approach not only complements the existing methods to access well-defined polymers but also has been successfully employed for the controlled polymerization of (meth)acrylates, styrenic monomers and solid acrylamides as well as the synthesis of polymer/perovskite hybrids without solvent at room temperature which are inaccessible by other means. Polymer materials suffer mechano-oxidative deterioration or degradation in the presence of molecular oxygen and mechanical forces. Here the authors demonstrate a synthetic approach in which molecular oxygen and mechanical energy synergistically initiate polymerization and affords robustness in polymeric materials. [ABSTRACT FROM AUTHOR]

Vapor‐phase propylene (C3H6) epoxidation kinetics with hydrogen peroxide (H2O2) strongly reflects the physical properties of Ti‐incorporated zeolite catalysts and the presence of spectating molecules ("solvent") near active sites even without a bulk liquid phase. Steady‐state turnover rates of C3H6 epoxidation and product selectivities vary by orders of magnitudes, depending on the zeolite silanol ((SiOH)x) density, pore topology (MFI, *BEA, FAU), and the quantity of condensed acetonitrile (CH3CN) molecules nearby active sites, under identical reaction mechanisms sharing activated H2O2 intermediates on Ti surfaces. Individual kinetic analyses for propylene oxide (PO) ring‐opening, homogeneous diol oxidative cleavage, and homogeneous aldehyde oxidation reveal that secondary reaction kinetics following C3H6 epoxidation responds more sensitively to the changes in zeolite physical properties and pore condensation with CH3CN. Thus, higher PO selectivities achieved in hydrophilic Ti‐MFI at steady‐state reflect the preferential stabilization of transition states for C3H6 epoxidation (a primary reaction) relative to PO ring‐opening and oxidative cleavage (secondary reactions) that solvation effects that reflect interactions among condensed CH3CN within pores and the extended pore structure. [ABSTRACT FROM AUTHOR]

Vapor‐phase propylene (C3H6) epoxidation kinetics with hydrogen peroxide (H2O2) strongly reflects the physical properties of Ti‐incorporated zeolite catalysts and the presence of spectating molecules ("solvent") near active sites even without a bulk liquid phase. Steady‐state turnover rates of C3H6 epoxidation and product selectivities vary by orders of magnitudes, depending on the zeolite silanol ((SiOH)x) density, pore topology (MFI, *BEA, FAU), and the quantity of condensed acetonitrile (CH3CN) molecules nearby active sites, under identical reaction mechanisms sharing activated H2O2 intermediates on Ti surfaces. Individual kinetic analyses for propylene oxide (PO) ring‐opening, homogeneous diol oxidative cleavage, and homogeneous aldehyde oxidation reveal that secondary reaction kinetics following C3H6 epoxidation responds more sensitively to the changes in zeolite physical properties and pore condensation with CH3CN. Thus, higher PO selectivities achieved in hydrophilic Ti‐MFI at steady‐state reflect the preferential stabilization of transition states for C3H6 epoxidation (a primary reaction) relative to PO ring‐opening and oxidative cleavage (secondary reactions) that solvation effects that reflect interactions among condensed CH3CN within pores and the extended pore structure. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Reversible addition‐fragmentation chain transfer (RAFT)‐mediated polymerization‐induced self‐assembly (PISA) of star block copolymer and linear block copolymer using a binary mixture of a star‐like macro‐RAFT agent and a linear macro‐RAFT agent is reported. With this formulation, star block copolymer and diblock copolymer were formed simultaneously to generate colloidally stable star/linear block copolymer assemblies. Size exclusion chromatography (SEC) analysis confirmed the presence of two types of polymers in the final samples. The molar ratio of the star‐like macro‐RAFT agent and the linear macro‐RAFT agent has a significant impact on the morphology of polymer assemblies. It was found that increasing the amount of star‐like macro‐RAFT agent facilitated the formation of higher‐order morphologies. Additionally, effects of other reaction parameters including the length/number of the arm of the star‐like macro‐RAFT agent, degree of polymer (DP), monomer concentration on the morphology of star/linear block copolymer assemblies were also investigated. We expect that this work will offer new possibilities for the scalable preparation of polymer assemblies with unique structures and functions. [ABSTRACT FROM AUTHOR]

Alternating current (AC) and pulsed electrolysis are gaining traction in electro(organic) synthesis due to their advantageous characteristics. We employed AC electrolysis in electrochemically mediated Atom Transfer Radical Polymerization (eATRP) to facilitate the regeneration of the activator CuI complex on Cu0 electrodes. Additionally, Cu0 served as a slow supplemental activator and reducing agent (SARA ATRP), enabling the activation of alkyl halides and the regeneration of the CuI activator through a comproportionation reaction. We harnessed the distinct properties of Cu0 dual regeneration, both chemical and electrochemical, by employing sinusoidal, triangular, and square‐wave AC electrolysis alongside some of the most active ATRP catalysts available. Compared to linear waveform (DC electrolysis) or SARA ATRP (without electrolysis), pulsed and AC electrolysis facilitated slightly faster and more controlled polymerizations of acrylates. The same AC electrolysis conditions could successfully polymerize eleven different monomers across different mediums, from water to bulk. Moreover, it proved effective across a spectrum of catalyst activity, from low‐activity Cu/2,2‐bipyridine to highly active Cu complexes with substituted tripodal amine ligands. Chain extension experiments confirmed the high chain‐end fidelity of the produced polymers, yielding functional and high molecular‐weight block copolymers. SEM analysis indicated the robustness of the Cu0 electrodes, sustaining at least 15 consecutive polymerizations. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Discovery of unprecedented donor‐acceptor patterns can essentially enrich the chemistry of donor‐acceptor cyclopropanes. We herein introduce a concept of vinylogous fluorine stabilizing effect, which guides rational design of a novel donor‐acceptor cyclopropane employing gem‐difluorovinyl group as the electron donor, namely dFVCP. Application of such dFVCPs in a [3+2] cycloaddition with aldehydes and a controlled ring‐opening polymerization by a Mg(OTf)2/DIPEA/C(sp3)‐H initiator system have been demonstrated, providing direct access to fluorine‐containing tetrahydrofurans and all‐carbon main‐chain polymers. [ABSTRACT FROM AUTHOR]

Topological growth control allows to produce a narrow distribution of outgrown colloidal rods with defined and adjustable length. We use an external magnetic field to assemble paramagnetic colloidal spheres into colloidal rods of a chosen length. The rods reside above a metamorphic hexagonal magnetic pattern. The periodic repetition of specific loops of the orientation of an applied external field renders paramagnetic colloidal particles and their assemblies into active bipeds that walk on the pattern. The metamorphic patterns allow the robust and controlled polymerization of single colloids to bipeds of a desired length. The colloids are exposed to this fixed external control loop that causes multiple simultaneous responses: Small bipeds and single colloidal particles interpret the external magnetic loop as an order to walk toward the active zone, where they assemble and polymerize. Outgrown bipeds interpret the same loop as an order to walk away from the active zone. The topological transition occurs solely for the growing biped and nothing is changed in the environment nor in the magnetic control loop. As in many biological systems the decision of a biped that reached its outgrown length to walk away from the reaction site is made internally, not externally. Topological growth control can produce colloidal rods with specific, adjustable lengths. Using an external magnetic field and metamorphic patterns, authors assemble paramagnetic colloidal spheres into walking bipeds, whose length determines their movement towards or away from an active zone. [ABSTRACT FROM AUTHOR]

Fluoropolymers are attractive due to their high resistance to external influences. However, they are poorly compatible with other materials (for example, paints and varnishes for the purpose of their hydrophobization). Compatibility can be improved by introducing hydrophilic monomer units. A convenient method is copolymerization with functional monomers. In this work, the method of controlled radical polymerization was chosen to resolve this problem, which makes it possible to obtain compositionally homogeneous samples of copolymers with reproducible properties. The reversible addition-fragmentation chain transfer (RAFT) polymerization of 2,2,2,3,3,4,4,5,5-octafluoropentylacrylate (OFPA), 1,1,1,3,3,3-hexafluoroisopropylacrylate (HFIPA), and glycidyl methacrylate (GMA) in the presence of 2-cyano-2-propyldodecyltritiocarbonate was first investigated. It was shown that CPDT is effective to control molecular weight characteristics of POFPA and GMA in concentration not more than 0.01 mol·L−1 and of PHFIPA − 0.03 mol·L−1. Copolymerization of fluorinated monomers (OFPA, HFIPA) and functional monomers (GMA) in the presence of low molecular (CPDT) and polymeric chain transfer agent was investigated. Reactivity ratios of monomers were determined by Fineman–Ross and Kelen–Tudos methods. The use of polymeric RAFT agent leads to instance of preferential solvation effect and formation of copolymer with gradient microstructure at final conversion in case of OFPA-GMA copolymerization. Thus, RAFT copolymerization of fluoroacrylates and GMA leads to formation of copolymers with block, gradient, or statistical microstructure that depended on synthesis condition. Block copolymers have amphiphilic properties and are able to form monomolecular films at the air/water interface. Further research will be aimed at modifying the resulting polymers using the epoxy group of GMA. This will make it possible to combine in one material both the properties of a surfactant (to stabilize acrylic dispersions) and a water repellent for paints. [ABSTRACT FROM AUTHOR]

The development of amphiphiles for sustained drug delivery represents a promising approach in biomedical fields. Polymeric self‐assembly with a hydrophobic core offers plenty of opportunities to encapsulate hydrophobic drugs for facilitating targeted delivery to the specific sites of action. Herein, N‐Boc tryptophan has been used to develop a hydrophobic monomer, Boc‐tryptophan‐HEMA (HBT). The HBT monomer has further been grafted on modified alginic acid through the RAFT technique to synthesize a unique amphiphilic copolymer with fluorescence characteristics. The advanced polymer chromatography demonstrates a narrow distribution curve, signifying the living nature of polymerization. The copolymer has exhibited self‐aggregation behavior with two distinct shapes at two different critical aggregation concentrations (CAC). The concentration‐dependent shape variation has been investigated using FESEM and TEM analyses, further supported by a small‐angle x‐ray scattering analysis. The self‐aggregation behavior of the copolymer facilitates the uptake of a model hydrophobic drug (naproxen) and its release in a sustained manner with varied rates at two different concentrations. [ABSTRACT FROM AUTHOR]

Mechanochemistry constitutes a burgeoning field that investigates the chemical and physicochemical alterations of substances under mechanical force. It enables the synthesis of materials which is challenging to obtain via thermal, optical or electrical activation methods. In addition, it diminishes reliance on organic solvents and provides a novel route for green chemistry. Today, as a distinct branch alongside electrochemistry, photochemistry, and thermochemistry, mechanochemistry has emerged as a frontier research domain within chemistry and material science. In recent years, the intersection of mechanochemistry with controlled radical polymerization has witnessed rapid advancements, providing new routes to polymer science. Significantly, we have experienced breakthroughs in methods relying on sonochemistry, piezoelectricity and contact electrification. These methodologies not only facilitate the synthesis of polymers with high molecular weight but also enable precise control over polymer chain length and structure. Transitioning from harsh to mild conditions in mechanochemical routes has facilitated a significant improvement in the controllability of mechanochemical polymerization. From this perspective, we introduce the progress of mechanochemistry in controlled radical polymerization in recent years, aim to clarify the historcial development of this topic. [ABSTRACT FROM AUTHOR]

Circular dichroism (CD) studies on poly(1,4‐phenylene)s bearing a chiral side chain in the aggregated conditions were carried out. Little CD was observed in a solution form, while addition of a poor solvent into the polyphenylene solution induced aggregation and a strong CD was observed, accordingly. Applying the controlled degree of polymerization (DP) of poly(1,4‐phenylene) in the use of bidentate diphosphine Chiraphos as a ligand for the nickel catalyst, the relationship of DP with CD strength was studied to reveal to show the highest CD at the DP=84 (gabs=ca. 2×10−2). It was also found that the related aggregation was observed in good solvent 1,2‐dichloroethane upon standing the solution at 4 °C for 3–23 days to observe gabs=ca. 10−1. Studies on the substituent effect of poly(1,4‐phenylene) suggested that CD behaviors were dependent on the type of non‐chiral substituent on the aromatic ring as well as the side‐chain chirality. [ABSTRACT FROM AUTHOR]

Atom transfer radical polymerization (ATRP) with dual photoredox/copper catalysis combines the advantages of photo-ATRP and photoredox-mediated ATRP, utilizing visible light and ensuring broad monomer scope and solvent compatibility while minimizing side reactions. Despite its popularity, challenges include high photocatalyst (PC) loadings (10 to 1000 ppm), requiring additional purification and increasing costs. In this study, we discover a PC that functions at the sub-ppm level for ATRP through mechanism-driven PC design. Through studying polymerization mechanisms, we find that the efficient polymerizations are driven by PCs whose ground state oxidation potential—responsible for PC regeneration—play a more important role than their excited state reducing power, responsible for initiation. This is verified by screening PCs with varying redox potentials and triplet excited state generation capabilities. Based on these findings, we identify a highly efficient PC, 4DCDP-IPN, featuring moderate excited state reducing power and a maximized ground state oxidation potential. Employing this PC at 50 ppb, we synthesize poly(methyl methacrylate) with high conversion, narrow molecular weight distribution, and high chain-end fidelity. This system exhibits oxygen tolerance and supports large-scale reactions under ambient conditions. Our findings, driven by the systematic PC design, offer meaningful insights for controlled radical polymerizations and metallaphotoredox-mediated syntheses beyond ATRP. Atom transfer radical polymerization with dual photoredox/copper catalysis often requires high photocatalyst loadings. Herein the authors report a photocatalyst that functions at the sub-ppm level for controlled radical polymerizations, focusing on a design strategy aimed at photocatalyst regeneration. [ABSTRACT FROM AUTHOR]

Polymerization‐induced self‐assembly (PISA) has emerged as a scalable one‐pot technique to prepare block copolymer (BCP) nanoparticles. Recently, a PISA process, that results in poly(l‐lactide)‐b‐poly(ethylene glycol) BCP nanoparticles coined ring‐opening polymerization (ROP)‐induced crystallization‐driven self‐assembly (ROPI‐CDSA), was developed. The resulting nanorods demonstrate a strong propensity for aggregation, resulting in the formation of 2D sheets and 3D networks. This article reports the synthesis of poly(N,N‐dimethyl acrylamide)‐b‐poly(l)‐lactide BCP nanoparticles by ROPI‐CDSA, utilizing a two‐step, one‐pot approach. A dual‐functionalized photoiniferter is first used for controlled radical polymerization of the acrylamido‐based monomer, and the resulting polymer serves as a macroinitiator for organocatalyzed ROP to form the solvophobic polyester block. The resulting nanorods are highly stable and display anisotropy at higher molecular weights (>12k Da) and concentrations (>20% solids) than the previous report. This development expands the chemical scope of ROPI‐CDSA BCPs and provides readily accessible nanorods made with biocompatible materials. [ABSTRACT FROM AUTHOR]

Functional polymers play an important role in various biomedical applications. From many choices, poly(2-isopropenyl-2-oxazoline) (PIPOx) represents a promising reactive polymer with great potential in various biomedical applications. PIPOx, with pendant reactive 2-oxazoline groups, can be readily prepared in a controllable manner via several controlled/living polymerization methods, such as living anionic polymerization, atom transfer radical polymerization (ATRP), reversible addition–fragmentation transfer (RAFT) or rare earth metal-mediated group transfer polymerization. The reactivity of pendant 2-oxazoline allows selective reactions with thiol and carboxylic group-containing compounds without the presence of any catalyst. Moreover, PIPOx has been demonstrated to be a non-cytotoxic polymer with immunomodulative properties. Post-polymerization functionalization of PIPOx has been used for the preparation of thermosensitive or cationic polymers, drug conjugates, hydrogels, brush-like materials, and polymer coatings available for drug and gene delivery, tissue engineering, blood-like materials, antimicrobial materials, and many others. This mini-review covers new achievements in PIPOx synthesis, reactivity, and use in biomedical applications. [ABSTRACT FROM AUTHOR]

The recovery process in bipolar disorder is a subjective and multidimensional experience that seeks to develop new meanings and purposes for living a satisfying life despite the limitations imposed by the disorder. Thus, this qualitative study aimed to explore the perceptions of recovery and the meanings attributed by individuals undergoing treatment for bipolar disorder to the elements considered relevant in this process. Semi-structured interviews with open-ended questions were conducted to explore the experiences and perspectives of recovery in individuals undergoing treatment for bipolar disorder. Grounded Theory was used as the method for qualitative analysis. The study included 26 participants aged between 18 and 65 years. Based on the analysis of participant reports, we identified two main themes: living with the illness and what it means to be in recovery. The perception of recovery is an individual process and can differ from the medical model. Participants suggest that accepting the diagnosis of bipolar disorder and finding meaning in life are essential to their recovery. They also describe how mental health professionals can facilitate or hinder this process. Understanding patients' perceptions can facilitate access to healthcare services and treatment adherence. [ABSTRACT FROM AUTHOR]

In vinyl/divinyl copolymerization, a crosslink is formed by the reaction between an active center and a pendant double bond. When both the active center and the pendant double bond are located within the same polymer molecule, the cyclization occurs, which is ineffective for growth in molecular weight. In the present model, the network dimension theory is applied to estimate the mean‐square radius of gyration for the growing polymer molecule, which is used to account for the enrichment effect of pendant double bonds around the active center for the cyclization reaction. The model is applied to the miniemulsion copolymerization, and both conventional free‐radical polymerization and ideal living polymerization are considered. Some of important characteristics of network architecture formed in these two types of polymerization mechanisms that cannot be predicted based on the classical chemical kinetics can be reproduced by the model, such unique characteristics as the pendant double bonds are consumed from the beginning of polymerization in the conventional free‐radical polymerization but not so in the living polymerization. The present model provides useful insights into the size and structural dependent network formation kinetics without relying on the lattice model. [ABSTRACT FROM AUTHOR]

Different approaches to achieve 2D supramolecular polymers, as an alternative to the covalent bottom‐up approaches reported for the preparation of 2D materials, are reviewed. The significance of the operation of weak non‐covalent forces to induce a lateral growth of a number of self‐assembling units is collected. The examples of both thermodynamically and kinetically controlled formation of 2D supramolecular polymers showed in this review demonstrate the utility of this strategy to achieve new 2D materials with biased morphologies (nanosheets, scrolls, porous surfaces) and showing elegant applications like chiral recognition, enantioselective uptake or asymmetric organic transformations. Furthermore, elaborated techniques like seeded or living supramolecular polymerizations have been demonstrated to give rise to complex 2D nanostructures. [ABSTRACT FROM AUTHOR]

Objective: To report our initial clinical experience with N-hexyl cyanoacrylate (NHCA), a novel liquid agent for neurovascular embolization. Methods: Four paragangliomas were treated with percutaneous embolization using NHCA as the sole embolic material. In one dural arteriovenous fistula (dAVF), NHCA was used in combination with other embolic materials. Procedural specifics, complications and angiographic results were retrospectively evaluated. Results: Total or subtotal devascularization was obtained in 3 of the 4 paragangliomas. In the largest tumor, only partial devascularization could be achieved. The dAVF was completely occluded. Catheter entrapment did not occur. After dAVF treatment, the patient had an asymptomatic lacunar infarction, while there was no procedural morbidity related to paraganglioma treatment. Conclusions: In this series, neurovascular embolization with NHCA was feasible and effective. It may be particularly beneficial for small and tortuous vessels that require low-profile catheterization and a slow and controlled polymerization. Further studies are necessary to prove the benefits of NHCA over established embolic agents. [ABSTRACT FROM AUTHOR]

Redox‐switchable catalysis is an efficient process to modulate the activity and/or selectivity in the polymerization with greater polymerization control and precision. In this work, the ferrocenyl‐functionalized diarylamines 4‐Fc‐C6H4NHC6H5 (HL1), 4‐Fc‐C6H4NH(2,6‐Me2C6H3) (HL2), and 2,6‐iPr2–4‐Fc‐C6H2NHC6H5 (HL3) were prepared and used as pro‐ligands to obtain the arylamido‐ligated rare‐earth metal complexes. Treatment of RE (CH2C6H4NMe2‐o)3 with 1 equiv. of HL1–3 in toluene afforded the ferrocenyl‐functionalized‐arylamido rare‐earth metal bis(o‐dimethylaminobenzyl) complexes L1Sc(CH2C6H4NMe2‐o)2 (1), L2RE(CH2C6H4NMe2‐o)2 (RE = Sc (2), Y (3)), and L3Y(CH2C6H4NMe2‐o)2 (4) in good yields. The compositions of these complexes were verified by NMR spectroscopy and elemental analysis. HL1 and HL3 were subjected to single‐crystal X‐ray diffraction. Electrochemical and NMR studies indicated that 4 could be oxidized with AgBF4 to generate the corresponding oxidized species 4ox, which could be facilely reduced back to 4 by use of CoCp2 as the reductant. The redox‐reversible ability between 4 and 4ox gave the chance to modulate the reactivity by switching the oxidized and reduced forms of one complex. For a controlled polymerization of ε‐caprolactone, 4 was active, and the polymerization process could be easily "on/off" switched by the redox reaction occurred on the ferrocenyl moiety. [ABSTRACT FROM AUTHOR]

Reversible addition‐fragmentation chain‐transfer polymerization, or RAFT, is a method for the controlled synthesis of block copolymers and an alternative to living ionic polymerizations. Although it is less susceptible to impurities, oxygen leads to inhibition of the polymerization. In a previous study, a model was developed to describe the inhibition kinetics of the RAFT polymerization of styrene. Based on this model, a detailed sensitivity analysis is performed with respect to the kinetic coefficients. While the formation of polyperoxides by oxygen addition shows high reaction rates, their further reactions (growth and termination) could be identified as rate‐determining steps. In addition, a proportional dependence of the duration of inhibition on the oxygen concentration was found. Based on the knowledge gained, a new initiation strategy with different thermal initiators to optimize polymerization was successfully tested using simulations. [ABSTRACT FROM AUTHOR]

Gas sensors based on conducting polymers offer great potential for high‐performance room temperature applications due to their cost‐effectiveness, high‐sensitivity, and operational advantage. However, their current performance is limited by the deficiency of control in conventional polymerization methods, leading to poor crystallinity and inconsistent material properties. Here, the quasi‐liquid layer (QLL) on the ice surface acts as a self‐regulating nano‐reactor for precise control of thermodynamics and kinetics in the polymerization, resulting in a 7.62 nm thick two‐dimensional (2D) polyaniline (PANI) film matching the QLL thickness. The ultra‐thin film optimizes the exposure of active sites, enhancing the detection of analyte gases at low concentrations. It is validated by fabricating a chemiresistive gas sensor with the 2D PANI film, demonstrating stable room‐temperature detection of ammonia down to 10 ppt in ambient air with an impressive 10% response. This achievement represents the highest sensitivity among sensors of this kind while maintaining excellent selectivity and repeatability. Moreover, the QLL‐controlled polymerization strategy offers an alternative route for precise control of the polymerization process for conducting polymers, enabling the creation of advanced materials with enhanced properties. [ABSTRACT FROM AUTHOR]

In the forefront of advanced materials, ultra-high molecular weight (UHMW) polymers, renowned for their outstanding mechanical properties, have found extensive applications across various domains. However, their production has encountered a significant challenge: the attainment of UHMW polymers with a low dispersity (Ɖ). Herein, we introduce the pioneering technique of ultrasound (US) initiated polymerization, which has garnered attention for its capability to successfully polymerize a multitude of monomers. This study showcases the synthesis of UHMW polymers with a comparatively low Ɖ (≤ 1.1) within a remarkably short duration (~ 15 min) through the amalgamation of emulsion polymerization and high-frequency ultrasound-initiated polymerization. Particularly noteworthy is the successful copolymerization of diverse monomers, surpassing the molecular weight and further narrowing the Ɖ compared to their respective homopolymers. Notably, this includes monomers like vinyl acetate, traditionally deemed unsuitable for controlled polymerization. The consistent production and uniform dispersion of radicals during ultrasonication have been identified as key factors facilitating the swift fabrication of UHMW polymers with exceptionally low Ɖ. Ultra-high molecular weight (UHMW) polymers exhibit exceptional mechanical properties and have found extensive applications, however, it remains challenging to produce them with a low dispersity. Here, the authors develop ultrasound-initiated copolymerization of diverse monomers, generating UHMW polymers with low dispersity within 15 min. [ABSTRACT FROM AUTHOR]

Achieving control over the polymerization of less activated monomers like N‐vinyl carbazole (NVC), N‐vinyl pyrrolidone (NVP), and N‐vinyl imidazole (NVIm) to produce high molar mass polymers poses a significant challenge. To accomplish this, eight different dithiocarbamate‐based reversible addition–fragmentation chain transfer (RAFT) agents are synthesized and employed to polymerize NVIm, NVC, and NVP in order to understand and establish a suitable agent for their controlled polymerization to achieve high molar mass polymers. Chain end presence of these RAFT‐derived polymers is established through 1H NMR studies. Further, these active chain ends are used for chain extension reactions to prepare block copolymers. Synthesized RAFT agents 04, 05, 06, and 08 that are bearing primary leaving groups (methyl 2‐acetate, ethyl 2‐acetate, tert‐butyl 2‐acetate, and cyanomethane) display moderate to good control over the polymerization of NVIm and NVC. Among these, RAFT agent‐08 with cyanomethane leaving group produces poly(NVIm) and poly(NVC) with the highest molar masses of 44 670 Da (1.52) and 53 620 Da (1.4), respectively. Interestingly, RAFT agents bearing both secondary and primary leaving groups show good control over the NVP polymerization. Notably, RAFT agent‐02 with ethyl‐2‐propionate leaving group yields poly(NVP) with the highest molar mass of 89 450 Da and dispersity of 1.43. [ABSTRACT FROM AUTHOR]

Metal halide perovskites have emerged as versatile photocatalysts to convert solar energy for chemical processes. Perovskite photocatalyzed polymerization draws special attention due to its straightforward synthesis process and the ability to create advanced perovskite‐polymer nanocomposites. Herein, this work employs Cs3Sb2Br9 perovskite nanoparticles (NPs) as a lead‐free photocatalyst for light‐controlled atom transfer radical polymerization (ATRP). Cs3Sb2Br9 NPs exhibit high reduction potential and interact with electronegative bromide initiator with Lewis acid Sb sites, enabling efficient photoinduced reduction of initiators and controlled polymerization under blue light irradiation. Methacrylate monomers with various functional groups are successfully polymerized, and the resulting polymer showcased a dispersity (Đ) as small as 1.27. The living nature of polymerization is confirmed by high chain end fidelity and kinetic studies. Moreover, Cs3Sb2Br9 NPs serve as heterogeneous photocatalysts, demonstrating recyclability and reusability for up to four cycles. This work presents a promising approach to overcome the limitations of lead‐based perovskites in photoinduced controlled radical polymerization, offering a sustainable and efficient alternative for the synthesis of well‐defined polymeric materials. [ABSTRACT FROM AUTHOR]

Redox organization governs an underlying simplicity in living systems. Critically, redox reactions enable the essential characteristics of life: extraction of energy from the environment, use of energy to support metabolic and structural organization, use of dynamic redox responses to defend against environmental threats, and use of redox mechanisms to direct differentiation of cells and organ systems essential for reproduction. These processes are sustained through a redox context in which electron donor/acceptor couples are poised at substantially different steady-state redox potentials, some with relatively reducing steady states and others with relatively oxidizing steady states. Redox-sensitive thiols of the redox proteome, as well as low molecular weight redox-active molecules, are maintained individually by the kinetics of oxidation-reduction within this redox system. Recent research has revealed opposing network interactions of the metallome, redox proteome, metabolome and transcriptome, which appear to be an evolved redox response structure to maintain stability of an organism in the presence of variable oxidative environments. Considerable opportunity exists to improve human health through detailed understanding of these redox networks so that targeted interventions can be developed to support new avenues for redox medicine. [Display omitted] • Opposing redox network interactions maintain stability in variable oxidative environments. • Network interactions exist for the metallome, proteome, transcriptome and metabolome. • Direct molecular antagonism can be discriminated from opposing network structures. • Diurnal redox oscillations could reflect opposing networks in redox stability. • Understanding of redox networks could support new avenues for redox medicine. [ABSTRACT FROM AUTHOR]

In this study, a novel iron-based catalyst system, Fe(acac)3/(isocyanoimino) triptenylphosphorane (IITP)/AlR3, was employed for the synthesis of syndiotactic 1,2-polybutadiene in hexane. This catalyst system exhibits remarkably high catalytic activity, achieving a polymerization activity of 762 kgpolymer·molcatalyst−1·h−1 at 50 °C with a [BD]/[Fe] molar ratio of 20000. Furthermore, living polymerization characteristic were observed during the investigation of the polymerization kinetics of 1,3-butadiene polymerization. These characteristics were well demonstrated by a narrow molecular weight distribution (PDI≈2.0) of the resulting polybutadiene and a linear relationship between–ln(1 − c) and polymerization time as well as number average molecular weight and polymer yield. The resultant polymer showed a 1,2-selectivity of approximately 76% and stereoregularity ranging from 62% to 73%(rrrr). Additionally, through kinetic studies on polymerization reaction, an apparent activation energy Ea value of this catalytic system was calculated to be 84.98 kJ·mol−1, which suggests that high polymerization temperature favors efficient polymerization. [ABSTRACT FROM AUTHOR]

I nnovative strides in polymer synthesis have led to the successful living anionic polymerization of styrene-olefin triblock copolymers, yielding varying molecular weights and a remarkably narrow dispersity (Đ) in cyclohexane solvent at 45°C, initiated by n-butyllithium. The novel approach employs anionic polymerization, augmented by the aid of a coupling agent known as 1,12-dibromododecane. Unlike traditional alcohol-based methods employed in polystyrene synthesis, this coupling agent, introduced at the end of the reaction, grafts two living macro-styrene chains with the dodecane chain, effectively acting as the pivotal second component in the formation of the triblock copolymer. Extensive experimentation pinpointed 45°C as the optimal temperature for anionic copolymerization in cyclohexane solvent. The comprehensive analysis, encompassing 13C NMR, ¹H NMR, FTIR spectroscopy, and GPC, confirms the successful synthesis of styrene-dodecane-styrene triblock copolymer. The NMR results illustrate successful molecular structures, while GPC attests to the precision, showing a narrow Đ of below 1.2. This pioneering approach not only underscores the efficiency of anionic polymerization in the synthesis of styreneolefin-styrene triblock copolymer using termination strategy but also promises extensive implications in material science and industrial applications. [ABSTRACT FROM AUTHOR]

Lewis pair polymerization (LPP) has made significant progress in recent decades as a powerful method to synthesize polymers. The matching of electronic and steric properties of Lewis base/acid plays a decisive role in the activity, controlled behavior, and initiation efficiency (I*) of the polymerization. However, exploration of aminophosphine based Lewis base for polymer synthesis has been limited. Herein, commercially available aminophosphine, namely hexamethylphosphorous triamide (HMPT) in combination with common organoaluminum for the polymerization of methyl methacrylate (MMA), is presented. HMPT/iBu3Al shows controlled behavior in MMA polymerization with polymerization degree from 48 to 800, affording defined polymethyl methacrylate (PMMA) with molecular weight (Mn = 15.1–110.7 kg mol−1) with relatively narrow molecular weight distributions (Ð = 1.11–1.37). Matrix‐assisted laser desorption/ionization time of flight mass spectroscopy (MALDI‐TOF‐MS) affirmed the chain‐end fidelity of PMMA. The interaction mode between Lewis pair affects the in situ generated fraction of active species. The basicity and the cone angle of the aminophosphine determine the activity of the formed active species and I*. The successful application highlights the benefits of introducing P─N bonds into Lewis bases, thereby expanding the variety of Lewis base categories. [ABSTRACT FROM AUTHOR]

Enzymes are nature's catalysts, mediating chemical processes in living systems. The study of enzyme function and mechanism includes defining the maximum catalytic rate and affinity for substrate/s (among other factors), referred to as enzyme kinetics. Enzyme kinetics is a staple of biochemistry curricula and other disciplines, from molecular and cellular biology to pharmacology. However, because enzyme kinetics involves concepts rarely employed in other areas of biology, it can be challenging for students and researchers. Traditional graphical analysis was replaced by computational analysis, requiring another skill not core to many life sciences curricula. Computational analysis can be time‐consuming and difficult in free software (e.g., R) or require costly software (e.g., GraphPad Prism). We present Enzyme Kinetics Analysis (EKA), a web‐tool to augment teaching and learning and streamline EKA. EKA is an interactive and free tool for analyzing enzyme kinetic data and improving student learning through simulation, built using R and RStudio's ShinyApps. EKA provides kinetic models (Michaelis–Menten, Hill, simple reversible inhibition models, ternary‐complex, and ping‐pong) for users to fit experimental data, providing graphical results and statistics. Additionally, EKA enables users to input parameters and create data and graphs, to visualize changes to parameters (e.g., KM or number of measurements). This function is designed for students learning kinetics but also for researchers to design experiments. EKA (enzyme-kinetics.shinyapps.io/enzkinet_webpage/) provides a simple, interactive interface for teachers, students, and researchers to explore enzyme kinetics. It gives researchers the ability to design experiments and analyze data without specific software requirements. [ABSTRACT FROM AUTHOR]

We report on the first case of the use of nonstoichiometric ternary (Ag–In–Zn–S) semiconductor nanocrystals as photoinitiators and photocatalysts of methyl methacrylate (MMA) polymerization. Two types of nanocrystals were tested, differing in their composition and characterized by red (λmax = 731 nm) and green (λmax = 528 nm) photoluminescence, respectively. Exploiting their reducing properties and capability of free radical generation we demonstrate that under ultraviolet (UV) radiation they effectively photoinitiate radical polymerization of MMA whereas under visible light (blue or green) they act as photocatalysts of living radical polymerization. [ABSTRACT FROM AUTHOR]

Despite their industrial ubiquity, polyolefin‐polyacrylate block copolymers are challenging to synthesize due to the distinct polymerization pathways necessary for respective blocks. This study utilizes MILRad, metal–organic insertion light‐initiated radical polymerization, to synthesize polyolefin‐b‐poly(methyl acrylate) copolymer by combining palladium‐catalyzed insertion–coordination polymerization and atom transfer radical polymerization (ATRP). Brookhart‐type Pd complexes used for the living polymerization of olefins are homolytically cleaved by blue‐light irradiation, generating polyolefin‐based macroradicals, which are trapped with functional nitroxide derivatives forming ATRP macroinitiators. ATRP in the presence of Cu(0), that is, supplemental activators and reducing agents , is used to polymerize methyl acrylate. An increase in the functionalization efficiency of up to 71% is demonstrated in this study by modifying the light source and optimizing the radical trapping condition. Regardless of the radical trapping efficiency, essentially quantitative chain extension of polyolefin‐Br macroinitiator with acrylates is consistently demonstrated, indicating successful second block formation. [ABSTRACT FROM AUTHOR]

It remains challenging to synthesize all‐(meth)acrylic triblock thermoplastic elastomers (TPEs), due to the drastically different reactivities between the acrylates and methacrylates and inevitable occurrence of side reactions during polymerization of acrylates. By taking advantage of the easy structural modulation features of N‐heterocyclic olefins (NHOs), we design and synthesize strong nucleophilic tetraphenylethylene‐based NHOs varying in the number (i.e. mono‐, dual‐ and tetra−) of initiating functional groups. Its combination with bulky organoaluminum [iBuAl(BHT)2] (BHT=bis(2,6‐di‐tBu‐4‐methylphenoxy)) constructs Lewis pair (LP) to realize the living polymerization of both acrylates and methacrylates, furnishing polyacrylates with ultrahigh molecular weight (Mn up to 2174 kg ⋅ mol−1) within 4 min. Moreover, these NHO‐based LPs enable us to not only realize the control over the polymers' topology (i.e. linear and star), but also achieve triblock star copolymers in one‐step manner. Mechanical studies reveal that the star triblock TPEs exhibit better mechanical properties (elongation at break up to 1863 % and tensile strength up to 19.1 MPa) in comparison with the linear analogs. Moreover, the presence of tetraphenylethylene group in the NHOs entitled the triblock TPEs with excellent AIE properties in both solution and solid state. [ABSTRACT FROM AUTHOR]

In biological systems, programmable supramolecular frameworks characterized by coordinated directional non‐covalent interactions are widespread. However, only a small number of reports involve pure water‐based dynamic supramolecular assembly of artificial π‐amphiphiles, primarily due to the formidable challenge of counteracting the strong hydrophobic dominance of the π‐surface in water, leading to undesired kinetic traps. This study reveals the pathway complexity in hydrogen‐bonding‐mediated supramolecular polymerization of an amide‐functionalized naphthalene monoimide (NMI) building block with a hydrophilic oligo‐oxyethylene (OE) wedge. O‐NMI‐2 initially produced entropically driven, collapsed spherical particles in water (Agg‐1); however, over a span of 72 h, these metastable Agg‐1 gradually transformed into two‐dimensional (2D) nanosheets (Agg‐2), favoured by both entropy and enthalpy contributions. The intricate self‐assembly pathways in O‐NMI‐2 enable us to explore seed‐induced living supramolecular polymerization (LSP) in water for controlled synthesis of monolayered 2D assemblies. Furthermore, we demonstrated the nonspecific surface adsorption of a model enzyme, serine protease α‐Chymotrypsin (α‐ChT), and consequently the enzyme activity, which could be regulated by controlling the morphological transformation of O‐NMI‐2 from Agg‐1 to Agg‐2. We delve into the thermodynamic aspects of such shape‐dependent protein‐surface interactions and unravel the impact of seed‐induced LSP on temporally controlling the catalytic activity of α‐ChT. [ABSTRACT FROM AUTHOR]