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Reliable thermodynamic and kinetic properties of free radical polymerization reactions are essential for synthesizing both primary polymeric materials and specialty polymers. The computational generation of these data from quantum chemistry requires a time-efficient method capable of capturing the essential physics. One such method, fixed-node diffusion Monte Carlo (FN-DMC) (using single Slater–Jastrow trial wavefunctions), has demonstrated the capability to recover 90%–95% of missing dynamic correlation energy for typical systems. In this study, methyl radical addition to ethylene serves as a simple model to test FN-DMC's ability to calculate enthalpies of reaction and activation energies with different time steps, antisymmetric trial wavefunctions, basis set sizes, and effective core potentials. The FN-DMC computational protocol thus defined for methyl radical addition to ethylene is subsequently benchmarked against Weizmann-1 and experimental reaction enthalpies from Lin et al.'s test set of 21 radical addition and 28 hydrogen abstraction enthalpies. Our findings reveal that FN-DMC consistently generates reaction enthalpies with chemical accuracy, exhibiting mean absolute deviation of 3.5(7) and 1.4(8) kJ/mol from the Weizmann-1 reference for radical addition and hydrogen abstraction reactions, respectively. Given its favorable computational scaling and high degree of parallelizability, we, therefore, recommend more comprehensive testing of FN-DMC with effective core potentials to address more extensive and intricate polymerization reactions and reactions with other radicals. [ABSTRACT FROM AUTHOR]

We present an approximate analytical approach to the adsorption problem of ABA triblock copolymers confined between two parallel plates in a θ solvent and give the expression of the propagator q(x, t) as a piece-wise function by solving the modified diffusion equation. In this way, the role of separation between the two plates, adsorption energy and block lengths on segment concentration profile, chain conformations, and interaction potential is then investigated, which agrees well with the numerical results. It is demonstrated that there are parallels between lengthening adsorbing A blocks and increasing surface affinity: strong adsorption and long adsorbing blocks favor the formation of loops and bridges, whereas more tails and free chains exist in the case of weak adsorption and short A blocks at large separations. For moderate and strong adsorptions, the bridging fraction begins to plummet at a separation larger than the end-to-end distance of non-adsorbing B block RB and becomes negligible at above 2RB owing to the entropy effect. The depth of the potential well in the interaction potential profile depends on the adsorption energy and A block length, while the location of the potential minimum corresponds to the onset of the sharp decrease in bridges. [ABSTRACT FROM AUTHOR]

Polymeric surfactants are amphiphilic molecules with two or more different types of monomers. If one type of monomer interacts favorably with a liquid, and another type of monomer interacts favorably with another, immiscible liquid, then polymeric surfactants adsorb at the interface between the two liquids and reduce the interfacial tension. The effects of polymer architecture on the structural and thermodynamic properties of the liquid–liquid interface are studied using molecular simulations. The interface is modeled with a non-additive binary Lennard-Jones fluid in the two-phase region of the phase diagram. Block and gradient copolymer surfactants are represented with coarse-grained, bead-spring models, where each component of the polymer favors one or the other liquid. Gradient copolymers have a greater concentration at the interface than do block copolymers because the gradient copolymers adopt conformations partially aligned with the interface. The interfacial tension is determined as a function of the surface excess of polymeric surfactant. Gradient copolymers are more potent surfactants than block copolymers because the gradient copolymers cross the dividing surface multiple times, effectively acting as multiple individual surfactants. For a given surface excess, the interfacial tension decreases monotonically when changing from a block to a gradient architecture. The coarse-grained simulations are complemented by all-atom simulations of acrylic-acid/styrene copolymers at the chloroform-water interface, which have been studied in experiments. The agreement between the simulations (both coarse-grained and atomistic) and experiments is shown to be excellent, and the molecular-scale structures identified in the simulations help explain the variation of surfactancy with copolymer architecture. [ABSTRACT FROM AUTHOR]

Block copolymers at homopolymer interfaces are poised to play a critical role in the compatibilization of mixed plastic waste, an area of growing importance as the rate of plastic accumulation rapidly increases. Using molecular dynamics simulations of Kremer–Grest polymer chains, we have investigated how the number of blocks and block degree of polymerization in a linear multiblock copolymer impacts the interface thermodynamics of strongly segregated homopolymer blends, which is key to effective compatibilization. The second virial coefficient reveals that interface thermodynamics are more sensitive to block degree of polymerization than to the number of blocks. Moreover, we identify a strong correlation between surface pressure (reduction of interfacial tension) and the spatial uniformity of block junctions on the interface, yielding a morphological framework for interpreting the role of compatibilizer architecture (number of blocks) and block degree of polymerization. These results imply that, especially at high interfacial loading, the choice of architecture of a linear multiblock copolymer compatibilizing surfactant does not greatly affect the modification of interfacial tension. [ABSTRACT FROM AUTHOR]

The domain reversal dynamics of the pristine and 10 wt. % BiFeO3 nanoparticle-embedded P(VDF-TrFE) (polyvinylidene fluoride-trifluoroethylene) flexible ferroelectric membranes were investigated. A scaling relation of A∝fαE0β relevant to the domain reversal dynamics was eventually determined. The pristine P(VDF-TrFE) flexible membrane takes the form of A∝f0.04077E00.39748 in stage III of high electric fields. Nevertheless, for BiFeO3-embedded P(VDF-TrFE) [BFO/P(VDF-TrFE)] flexible membranes, the relations are developed as A∝f−0.3326E02.74911 in the low electric fields of stage I and as A∝f0.04309E01.04872 in stage III separately. The negative α indicates that more and more domain reversal lags behind the alternating periodic electric field in stage I. Instead, in stage III, the positive α indicates that most domain reversals can occur anytime whatever the alternating speed of electric fields is. Analogously, the positive β indicates that at any selected frequency, domains can flip at an external electric field. Abnormally, for the pristine P(VDF-TrFE) membrane, the scaling relation in the first E0 stage is broken, reflecting only dielectric contributions this time. The dynamic scaling data are significant for the micromechanism accomplishments of copolymers and for the designs of flexible electric devices. [ABSTRACT FROM AUTHOR]

The development of sustainable polymer materials, such as biodegradable aliphatic polyesters and natural polymers, has recently become an important issue because of the environmental impact of plastic waste. In this study, we demonstrate the novel synthesis of self-assembling peptide-grafted polyesters. The graft copolymers were prepared via radical ring-opening copolymerization of 2-methylene-1,3-dioxolane (C5), a five-membered cyclic ketene acetal, and tetraleucine peptide macromonomers (MA-Leu4-Am) with various feed compositions, and their structures were characterized by 1H NMR, SEC, and FT-IR analyses. The ring-opening ratio (Rop) of C5 units was almost constant at 70–85% regardless of the feed compositions. In contrast, the values of the grafting ratio of the peptide chain (Gr) were remarkably higher than the values calculated from the feed composition of C5 and MA-Leu4-Am (Gr,feed), reflecting their monomer reactivities. To characterize the copolymerization behavior in detail, density functional theory (DFT) calculations were performed to elucidate the copolymerization mechanisms. These calculations demonstrated that radicals derived from C5 preferentially react with the peptide macromonomer, which was supported by the calculated reaction rate constants and monomer reactivity ratios. [ABSTRACT FROM AUTHOR]

Multi‐responsive, self‐healing hydrogels were developed utilizing positively charged polysaccharides, chitosan, and water‐soluble chitosan. This fabrication employed free‐radical synthesized polyacrylic acid and polymethacrylic acid along with the cross‐linker FeCl3, resulting in the generation of polyelectrolyte metal complexes, which enhances the properties of the chitosan‐based hydrogels, particularly their mechanical strength, self‐healing ability, thermal stability, swelling behavior, porous structure, cell viability, and even anticancer activity. Characterization and stability assessment of the hydrogels were performed using FT‐IR, nuclear magnetic resonance, gel permeation chromatography, scanning electron microscopy, rheometer, x‐ray diffraction, thermogravimetric analysis, DSC, and UV spectroscopy. FT‐IR measurements indicated that the facile complexation of the cross‐linker's metal ions (Fe3+) with the carboxylate (COO−), amino (NH), and hydroxyl (OH) groups of the polymers and chitosan chains facilitated rapid gelation. Furthermore, the sustained release of the drug levofloxacin (up to 80%) was observed to increase with increasing pH due to the hydrogels' anionic nature. Biocompatibility and cytotoxicity tests were conducted using the MTT assay on splenocytes and Dalton Lymphoma cancer cell lines. These tests demonstrated the promising potential of these hydrogels for drug delivery applications. [ABSTRACT FROM AUTHOR]

The increasing water pollution problem poses a demand for oil–water separation materials, but preparing separation materials with high efficiency and excellent durability remains a great challenge. In this work, we use a diblock polymer brush of polydimethylsiloxane (PDMS) and poly(N,N‐dimethylaminoethyl methacrylate) (PDMAEMA) based on cotton fabric to prepare oil–water separation membranes with high efficiency, good durability, and intelligent self‐repairing properties. Lubricating PDMS brushes reduces the fouling adhesion due to its low surface energy and high flexibility. pH‐responsive PDMAEMA brushes provide good hydrophobicity and an intelligent self‐repairing effect. The prepared Co‐PDMS‐PDMAEMA has high oil flux (>30,000 L m−2 h−1) and high separation efficiency (>99%) even after 10 cycles and its surface character can be recovered under acidic conditions. Overall, the modified cotton fabric made by such a versatile technique is promising in oil–water separation. [ABSTRACT FROM AUTHOR]

Data on the solubility of oligomer polystyrene and random copolymers of styrene and methyl methacrylate with different styrene contents have been obtained. Phase diagrams were constructed and the values of critical points were determined. The upper critical solution temperature is localized in the temperature range above 420 K and grows with increasing molecular weight of PS and decreasing styrene content in the copolymer. Based on the compositions of the coexisting phases, paired interaction parameters were calculated and their temperature dependences were plotted. The dependence of the interaction parameter on the copolymer composition and the correlation dependence between its enthalpy and entropy components were constructed. A method for simulation phase equilibrium for copolymers of arbitrary composition and molecular weight is proposed. [ABSTRACT FROM AUTHOR]

This paper presents the results of an experimental study on the intensity of evaporation of polymers (polytetrafluoroethylene, polyamide-6, acetal homo- and copolymers, polyethylene, and polyvinyl chloride) under the influence of a pulsed discharge. First, the dynamics of evaporation of the surface of polymer samples by radiation from the discharge channel was studied using shadowgraphy (schlieren photography), and then a unit force impulse created by a vapor–plasma flow accelerated in the discharge was determined. It has been shown that polyvinyl chloride and polyethylene have the highest evaporation rate and, accordingly, create a higher force impulse. [ABSTRACT FROM AUTHOR]

In order to design novel bio-based and water-degradable polyesters with high heat resistance and good mechanical properties, we synthesized a series of poly(neopentyl glycol succinate-co-isosorbide succinate) (PNSI)-based isosorbide building blocks via melt polycondensation. The molar content of isosorbide succinate ranged from 20 to 70%. The kinetics of thermal decomposition showed that with an increase in the isosorbide molar content, the degradation activation energy (Ea) of the copolyesters significantly increased. From Kissinger and Flynn–Wall–Ozawa models, the Ea of PNSI copolymer with 40% molar content of isosorbide succinate segment content was 92.7 and 104.5 kJ mol−1, respectively, which was higher than PNS copolymers (69.1 kJ mol−1 and 87.7 kJ mol−1). In addition, the isosorbide structure containing hydrophilic ether bonds increased the degradation rate of polyester. The weight loss of the PNSI40 copolymer was greater than 89% after 42 days of degradation in an alkaline solution. This study showed that the bio-based monomer isosorbide could balance thermal properties (especially Tg) and water/biodegradability. In addition, the copolymer is nontoxic; thus, the PNSI copolymer is an ideal membrane material with a wide range of packaging applications. [ABSTRACT FROM AUTHOR]

This study introduces the first fluorene‐flanked diketopyrrolopyrrole (FDPP)‐based semiconducting polymers, named Boc‐FDPP‐CoMs (CoM = TT or BT), synthesized via copolymerization of tert‐butoxycarbonyl (t‐Boc)‐substituted FDPP as the acceptor unit with thieno[3,2‐b]thiophene (TT) or bithiophene (BT) as the donor comonomers. The incorporation of t‐Boc groups addresses challenges related to poor solubility and polymer backbone twisting associated with the FDPP building block. While Boc‐FDPP‐CoMs demonstrate solubility in common organic solvents, facilitating favourable solution‐processability for uniform film fabrication, they exhibit significant backbone twisting, leading to poor charge transport properties. Post‐deposition thermal annealing at a mild temperature as low as 170°C conveniently removes t‐Boc groups. The resulting t‐Boc‐free copolymers, NH‐FDPP‐TT and NH‐FDPP‐BT, exhibit hole mobilities up to 5.0 × 10−3 and 2.2 × 10−3 cm2 V−1 s−1 in organic field effect transistors (OFETs), respectively, representing a substantial increase compared to their counterparts with t‐Boc groups. This study underscores a meticulously designed strategy for achieving solution solubility and backbone coplanarity through side‐chain engineering for FDPP and potentially other sterically demanding building blocks to construct high‐performance semiconducting polymers for OFETs and other applications. [ABSTRACT FROM AUTHOR]

Although seeded reversible addition‐fragmentation chain transfer (RAFT) polymerization is explored as a unique method for the preparation of block copolymer nanoparticles with diverse structures, the preparation of nonlinear polymer nanoparticles by seeded RAFT polymerization is rarely reported. Herein, linear block copolymer nanoparticles are first prepared by RAFT dispersion copolymerization of benzyl methacrylate (BzMA) and 2‐(2‐(n‐butyltrithiocarbonate)propionate)ethyl methacrylate (BTPEMA) with different [BzMA]/[BTPEMA] ratios, and employed as seeds for seeded RAFT polymerization of isobornyl acrylate (IBOA) to prepare graft copolymer nanoparticles with different numbers of PIBOA side chains. Comparing with linear triblock copolymers with the same chemical composition, the graft copolymers can promote the formation of higher‐order morphologies (e.g., vesicles) under seeded RAFT polymerization conditions. Effects of reaction parameters on the morphology of graft copolymer nanoparticles are investigated in detail, and two morphological phase diagrams are constructed. It is expected that this study will not only expand the scope of seeded RAFT polymerization but also offer new opportunities for the preparation of unique polymer nanoparticles. [ABSTRACT FROM AUTHOR]

Water‐resistant porous solid foams expressing a high amount of benzene sulfonate moieties have been fabricated to enhance the adsorption of cationic aromatic pollutants from wastewaters by aromatic–aromatic interactions. Copolymers of sodium 4‐styrene sulfonate (NaSS) and glycidyl methacrylate (GMA) have been obtained and submitted to thermal treatment at 270 °C for 15 min. The influence of the solvent used in the copolymerization step on foamability and foam stability, when formed, has been studied. The use of water as cosolvent with N,N‐dimethyl formamide (DMF) inhibited foam formation. The use of DMF or DMF/dimethyl sulfoxide (DMSO) = 1:1 as solvents allowed the expansion of copolymers, but the resulting foams are unstable in water, forming hydrogels. However, using DMF/DMSO = 5:1 as solvent, stable water‐resistant foams showing NaSS molar fractions of 43, 57, and 68% are obtained, showing high maximum capacity of 244, 435 and 588 mg g−1 and outstanding pseudo‐second‐order kinetic constants of 1.78, 4.49 and 5.64 g mg−1 min−1 toward adsorption of methylene blue (MB), between 2 and 5 orders‐of‐magnitude higher than referenced adsorbents. This is due to the highly exposed benzene sulfonate active sites / adsorbent mass ratio that induces strong aromatic–aromatic interactions with the cationic aromatic dye. [ABSTRACT FROM AUTHOR]

The combination of aromatic and aliphatic structures can endow polyurea with distinct performance advantages. A one‐step feeding method is used to synthesize linear hybrid aliphatic/aromatic copolyureas by varying the ratio of m‐phenylenediamine (MPD) and polyoxypropylenediamine (D2000) reacting with 4,4′‐diphenylmethane diisocyanate (MDI). Real‐time Fourier‐transform infrared spectrometer monitoring reveals that D2000 exhibits higher reactivity than MPD. Consequently, in the MDI/MPD/D2000 system, D2000 initially reacts with MDI to form an isocyanate‐terminated prepolymer, which subsequently reacts with MPD. Compared with the two‐step feeding method, this approach successfully eliminates biuret formation and enhances tensile strength. Additionally, decreasing the molar ratio of D2000 to MPD (λm) reduces the size and degree of microphase separation in the polyurea by increasing the ordered hydrogen bonding and benzene conjugation, leading to an increase in tensile strength. Specifically, as λm decreases from 70 mol% to 30 mol%, the degree of microphase separation decreases from 0.47 to 0.2, causing the tensile strength to rise from 28 to 48 MPa. Further reducing λm to 30 mol% decreases the degree of microphase separation to 0.16, resulting in an increase in tensile strength to 78 MPa. [ABSTRACT FROM AUTHOR]

Self‐assembly behaviors of special topological polymers such as 8‐figure shaped cyclic polymer are interesting, but are rarely reported so far due to the limited availability. In this work, mikto 8‐figure shaped cyclic copolymers are synthesized with cinnamic acid dimer junctions, in which both rings possess diblock PSx‐b‐PEGy structures. Their self‐assembly in water is investigated in comparison with their corresponding linear precursors. According to scanning electron microscopic (SEM) and transmission electron microscopic (TEM) observation, both of the mikto 8‐figure shaped cyclic polymers and their corresponding linear precursors can form vesicles. But those formed from the former have very smooth surfaces, while those from the linear precursors have rugous surfaces. TEM observation shows that the linear precursors form loose vesicles. The size of micelles formed from 8‐shaped cyclic copolymers is much smaller than that formed from the linear precursors. The topological structure exerts a significant influence on the solution aggregation behavior and provides broad ideas for the construction of precision solution aggregates. [ABSTRACT FROM AUTHOR]

Statistical copolymers are commercially important because their properties can be tuned by comonomer selection and composition. Rubbery‐state styrene (S)/n‐butyl acrylate (nBA) copolymers have previously been reported to exhibit facile, autonomous self‐healing over a narrow composition band (47/53 to 53/47 mol%). The need for a narrow composition band is explained by alternating comonomer sequences that accommodate interchain secondary bonding. It is hypothesized that copolymers that achieve interchain secondary bonding without alternating sequences can exhibit facile self‐healing over a broad composition range. 2‐ethylhexyl acrylate (EHA) is identified as yielding sequence‐independent secondary bonding interactions. For these interactions it is tested experimentally by glass transition breadth in rubbery‐state S/EHA copolymers, with S/n‐hexyl acrylate (nHA) and S/nBA copolymers as controls. The n‐alkyl acrylate random copolymers exhibit enhanced glass transition breadths over narrow composition bands that correspond to autonomous self‐healing. In contrast, S/EHA copolymers exhibit much greater glass transition breadths than S/nHA and S/nBA copolymers at all compositions tested as well as self‐healing of damage over a broad composition range with full tensile‐property recovery, often in 3–10 h. Characterization of glass transition breadth may serve as a simple screening tool for identifying copolymers that exhibit broad‐composition‐range, facile, autonomous self‐healing and contribute to polymer resilience and sustainability. [ABSTRACT FROM AUTHOR]

The furan/maleimide Diels–Alder (DA) reaction has been exploited to construct thermally reversible macromolecular structures, such as linear or cross-linked polycondensates, or to cross-link linear polymers, using the free end-type or pending furan and maleimide moieties as the diene and dienophile reagents. Here we report a different approach for the synthesis of homopolymers based on a diol, in which the DA adduct formed by the furan and the maleimide sits within the diol monomer structure. The OH end groups of the diol were used for the synthesis of a polyester and a polyurethane using conventional polycondensation methods and to study their retro DA (rDA) depolymerization through the thermal decomposition of their inner DA adducts. The relevant contribution of this study was however the possibility of synthesizing a copolymer by heating these two polymers together to induce their rDA deconstruction and then lowering the temperature in order to allow the ensuing fragments to recombine statistically by successive DA couplings, thus building the corresponding ester-urethane copolymer. 1H NMR spectroscopy and DSC analysis were employed to confirm the success of this promising approach. [ABSTRACT FROM AUTHOR]

This article reports the synthesis of a novel perfluoropolyalkylether (PFPAE) vinylether monomer and its use as a comonomer in the thiol‐ene photopolymerization of a trifunctional thiol together with a trifunctional vinylether. The crosslinked copolymers are obtained in the form of few mm thick layers and characterized. By changing the thiol/ene ratio, the polymers are optimized to tailor their surface composition and obtain adhesion between two thick layers despite the presence of the fluorinated monomer. The final bilayered structures are adhesive, and appeared chemically resistant, with good dimensional stability: therefore, these fluorinated thiol–ene based copolymers are likely to be of interest for applications based on layer‐by‐layer processes, such as additive manufacturing and microfluidics. [ABSTRACT FROM AUTHOR]

To explore the influence of reaction medium on the copolymerization behavior of acrylamide‐based copolymers, three types of copolymers (P(AM‐St)(ILs), P(AM‐MMA)(ILs), and P(AM‐AMPS)(ILs)) were synthesized by combining insoluble, slightly soluble, and easily soluble monomers with acrylamide in the 1‐butyl‐3‐methylimidazolium tetrafluoroborate ([BMIM]BF4) reaction medium. The reactivity ratio, Fourier transform infrared spectroscopy, 1H NMR spectroscopy, elemental analysis, and scanning electron microscopy were employed to characterize the copolymers' properties. The results indicated that in [BMIM]BF4 copolymerization, the reactivity ratio of AM and St in P(AM‐St)(ILs) decreased, the reactivity ratio of AM in P(AM‐MMA)(ILs) will increase. While the reactivity ratio of MMA will decrease. The reactivity ratio of AM in P(AM‐AMPS)(ILs) will increase and the reactivity ratio of AMPS will decrease. The distribution of AM and St segments in P(AM‐St)(ILs) molecular chains is more uniform and compact. When AM polymerizes with hydrophobic monomers (St) in [BMIM]BF4, its copolymer solution exhibits lower viscosity loss rates in temperature, shear, and salt resistance tests. Therefore, ionic liquids are more suitable as reaction media for the synthesis of hydrophobic‐modified polyacrylamides, which facilitate a more uniform distribution of hydrophobic monomers within the copolymer chains and exhibit enhanced resistance to temperature, salt, and shear stresses. [ABSTRACT FROM AUTHOR]

The durability of anion exchange membranes (AEMs) and the balance between ionic conductivity and dimensional stability have been the focus of research. To this end, we propose a new type of AEMs with vinyl imidazole as the in situ cross‐linking monomer. The rigid‐flexible balance within the membrane was adjusted by changing the arrangement of the internal segments of the polymer and introducing different monomers into the main chain. The results showed that the performance of AEMs could be effectively improved by adopting an ether‐free backbone and a cationic cross‐linking strategy. The swelling rate of all AEMs was less than 20%. The ionic conductivity of BDCP‐80 reached 102.74 mS cm−1 at 80°C. Alkaline stability tests showed that the ionic conductivity of all AEMs remained above 82% after 720 h immersion in 2 M NaOH solution at 80°C. This study demonstrated that the simple in situ cross‐linking method can effectively improve the overall performance of AEMs and provide an effective way to develop high‐performance AEMs. [ABSTRACT FROM AUTHOR]

Semi‐aromatic nylon MXD6 shows superior mechanical strength and gas barrier properties. To improve its toughness and get sight into its excellent properties, a series of poly(m‐xylylene adipamide‐co‐isophthalamide) (MXD6/I) random copolyamides were synthesized using adipic acid, isophthalic acid (IPA) and m‐xylylene diamine as monomers via direct melt polycondensation. The effect of IPA content on the thermal, crystallization, heat resistant, mechanical, and barrier properties of the copolyamides were systematically investigated. The results showed that the increase of IPA content from 0 to 12 mol% resulted in a decrease in the melting point of the copolyamides from 238 to 217°C but the glass transition temperature (Tg) increased from 88 to 105°C. Correspondingly, the Vicat softening temperature decreased from 199.2 to 172.5°C. The crystallization rate of the copolyamides significantly decreased with the increase of the IPA content. The copolyamides had improved elongation and rupture energy and decent oxygen barrier properties with the introduction of IPA. It is expected that this study would guide design of MXD6 macromolecular chain structure to prepare high‐performance MXD6 materials. [ABSTRACT FROM AUTHOR]

In order to achieve flame retardant, hydrophobic, and toughened epoxy resins, phosphorus/fluorine‐containing block copolymer (FBCP) was synthesized by reversible addition‐fragmentation chain transfer polymerization, and then the as‐synthesized PMADOPO‐b‐PHFBA block copolymer was used as additive to modify the epoxy resin, accompanying with a random copolymer (FRCP) serving as control group. It showed that due to the regular arrangement of molecular chains, FBPC formed a fibrous‐like structure at the fracture interface of epoxy/PMADOPO‐b‐PHFBA (EP/FBCP) samples, effectively enhancing the toughness of epoxy composite materials. The fracture energy of EP90/FBCP‐10 was higher than that of EP90/FRCP‐10 and was about twice than that of pure EP. The addition of 3 wt% FBCP could enhance the limited oxygen index (LOI) of EP97/FBCP‐3 to 33.2% and reached a V‐1 UL‐94 rating. As the addition of FBCP increased, the LOI gradually increased. When the addition of FBCP was 10%, the LOI and UL‐94 of EP90/FBCP‐10 was 38.2% and V‐0 grade, respectively. Meanwhile, the presence of fluorine element effectively reduced the surface energy of the composite EP material. Compared with pure EP, the water contact angle of EP90/FBCP‐10 was about 101° with an increasing of 20.8%. Furthermore, the flame‐retardant mechanism of EP/FBCP epoxy composites was discussed. [ABSTRACT FROM AUTHOR]

A pH responsive monometallic‐clay nanocomposite hydrogel, sodium alginate‐cl‐poly (N‐hydroxy ethyl acrylamide‐co‐methacrylic acid) @ Au/ montmorillonite clay (SANCHG@Au/MMT) is synthesized in situ using sodium alginate (SA) as a polysaccharide. Two other nano composite hydrogels namely sodium alginate‐cl‐poly (N‐hydroxy ethyl acrylamide‐co‐methacrylic acid) @ Au (SANCHG@Au) and sodium alginate‐cl‐poly (N‐hydroxy ethyl acrylamide‐co‐methacrylic acid) @ montmorillonite clay (SANCHG@MMT) are also prepared. All the synthesized nano composite hydrogels are characterized using various techniques. Water swelling of the three hydrogels along with their textile dye adsorption properties is evaluated in congo red (CR), benzopurpurin (BP) and tartrazine (TZ) from their aqueous solutions. Among the three hydrogels the % water swelling of SANCHG@Au/MMT is superior (396% at pH = 8) and also the adsorption capacity over the other two. The dye adsorption property of SANCHG@Au/MMT is found to be pH sensitive. Adsorption follows both the Langmuir adsorption isotherm with Qmax values 512.19 mg.g−1 for CR at pH = 4, 476.09 mg.g−1 at pH = 4 for BP and 454.79 mg.g−1 at pH = 6 for TZ respectively and Dubinin–Radushkevich isotherm model. The kinetic data fit with pseudo second order kinetic model. Thermodynamic parameters like negative ∆G0 and positive ∆H0 values suggest that the adsorption process is spontaneous and endothermic in nature. [ABSTRACT FROM AUTHOR]

The effects of grafting level of polyethylene glycol (PEG) grafted styrene ethylene propylene styrene (SEPS) on the intrinsic brittleness of epoxy thermosets were studied. The SEPS‐g‐PEG block copolymer (BCP) was synthesized by grafting various grafting degree of PEG (i.e., 10%, 20%, 30%, and 40%) on polystyrene (PS) blocks of SEPS following Williamson ether synthesis method. A total of 10 wt% of the BCP modifiers were dispersed in epoxy thermosets. PEG side chains were miscible in the epoxy which formed a uniform BCP dispersion within the epoxy thermoset matrix. As the degree of PEG grafting was increased, the BCP phase was absorbed in the epoxy matrix. This absorption occurred because the increase in PEG grafting provided more miscible PEG chains to bind the BCP and epoxy nanostructures together. The differential scanning calorimeter and dynamic mechanical thermal analysis analyses indicated that BCP toughened epoxy exhibited an improved glass transition temperature (Tg). At a 40% PEG grafting degree in the BCP, the critical stress intensity factor (KIC) and critical strain energy release rate (GIC) increased up to 80% and 180%, respectively. This trend suggested that the energy associated with fractures could be absorbed through the deformation of the softer phases when a load was applied to them. [ABSTRACT FROM AUTHOR]

Cytarabine, also known as cytosine arabinoside is an anticancer drug, and it is widely used to treat acute myeloid leukemia (AML). But, clinical efficacy of highly hydrophilic cytarabine is often limited due to its rapid degradation and high biodistribution. Hence, this study aims to enhance the anticancer effect of cytarabine with the help of a naturally occurring polyphenol, curcumin. The interaction between cytarabine and curcumin was established by different spectroscopic techniques like UV–Visible, fluorescence, and Fourier transform infrared (FT‐IR). Molecular interactions were also studied using isothermal calorimetric titrations (ITC) followed by theoretical docking. The involvement of the amine group of cytarabine with the interaction of curcumin has been supported by FT‐IR and docking study. However, the major challenge with curcumin is that, in spite of its several medicinal benefits, poor solubility and bioavailability restricts its potential clinical applications. Hence, polymersome‐encapsulated curcumin (PEC) was prepared for the intravenous application. A two‐fold decrease in IC50 value of cytarabine against HeLa cell line was found in presence of encapsulated curcumin. This was justified on the basis of observed reactive oxygen species enhancement in serum in presence of cytarabine and PEC together, determined using absorption spectroscopy. The enhanced affinity of cytarabine toward DNA‐curcumin complex as compared to free DNA, supported by theoretical study, also validates the increased cytotoxicity of cytarabine in presence of PEC. [ABSTRACT FROM AUTHOR]

Recently, environmental applications of copolymers such as CO2 capture and separation have become of significant interest. The development of copolymers with basic functional groups, such as amidoxime (AO) groups, represents a successful approach for enhancing absorption and separation of acidic molecules, such as CO2. In this research, acrylonitrile/N-vinyl imidazole (AN/VIM) copolymers were first synthesized through a free radical copolymerization method using 2,2′-azobisisobutyronitrile (AIBN) as the initiator and dimethylformamide as the solvent. The synthesized copolymers were then functionalized using hydroxylamine hydrochloride (NH2OH · HCl), the result being amidoximated (AO) copolymers. The synthesized copolymers were characterized by nuclear magnetic resonance (NMR) spectroscopy, thermogravimetric analysis and Fourier transform infrared spectroscopy. The analytical results simply confirmed that the copolymers and their amidoximated derivatives had successfully been synthesized. A microstructural study of amidoximated polymers using NMR spectroscopy clearly showed the tautomerization of AO groups. [ABSTRACT FROM AUTHOR]

Polyolefin elastomers are typically copolymers of ethylene with 1-butene, 1-hexene, or 1-octene. Other types of comonomers have not been widely applied industrially. The cost of 1-heptene obtained from Fischer-Tropsch synthesis is only half that of 1-octene, making it a viable economical substitute. This work utilized 1-heptene from Fischer-Tropsch synthesis and 1-octene from ethylene oligomerization as research subjects. Eight metallocene POEs based on 1-heptene and 1-octene were synthesized using Me2Si(C5Me4)(NtBu)]TiCl2 (Ti-CGC) catalyst. The copolymers' molecular structures and physical properties were characterized using HT-GPC, Temperature Rising Elution Fractionation (TREF),13C-NMR, DSC, Melt Index (MI), and Tensile tests. Compared to 1-heptene, 1-octene more effectively reduces the melting point and crystallinity, while 1-heptene's stronger comonomer insertion capability facilitates the production of copolymers with higher comonomer content. Similar ternary sequence distributions and molecular dynamics indicate that ethylene/1-heptene and ethylene/1-octene copolymers possess comparable chain microstructures. Both ethylene/1-heptene copolymers and ethylene/1-octene copolymers exhibit excellent toughness and mechanical properties. Although the activity and insertion capacity of ethylene and 1-heptene decrease at low comonomer concentrations, they significantly improve at higher comonomer concentrations. Thus, Fischer-Tropsch synthesis of metallocene ethylene/1-heptene copolymers can effectively reduce raw material costs and be a cost-effective alternative to ethylene/1-octene copolymers. [ABSTRACT FROM AUTHOR]

Here, we report a reprocessible, reusable, self-healing, and form-switching polymeric adsorbent for remediating fluorinated pollutants in water. The copolymer hydrogel is designed to contain fluorophilic segments and cationic segments to induce strong binding with perfluorinated pollutants. The sorption performance reveals rapid and quantitative removal of these pollutants, driven by the synergistic effect of fluorophilic and electrostatic interaction. Importantly, a disulfide-containing dynamic crosslinker plays a crucial role in imparting multifunctionality. This enables self-healing by the restoration of crosslinks at the cut surfaces by disulfide exchange reactions and allows for the repeated use of the adsorbent via multiple adsorption–desorption cycles. Furthermore, the adsorbent is reprocessible by cleaving the crosslinks to afford linear copolymers, which can be repolymerized into a hydrogel network on demand. Also, form-switching capability is showcased through the aqueous self-assembly of linear copolymers into a fluorinated micelle, serving as another form of adsorbent for pollutant removal. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Converting CO2 into valuable chemicals is an effective means to alleviate environmental pressure and the depletion of oil resources. Among them, polymers derived from the copolymerization of PO and CO2 have been widely studied because of their excellent properties. To meet the expansion of the application range of CO2‐based polymers, regulation of the CU in the polymer is imperative. Based on the understanding of the relationship between catalyst synergy and structure, we designed a new generation of polyester‐based polymeric catalysts APEPC‐R and RPEPC‐N with discretely distributed active centers to achieve the synthesis of CO2‐based polymers with regulated CU (from 50% to 90%). The discrete arrangement of catalyst active centers was demonstrated by 1H NMR and UV‐vis characterization. Benefiting from multi‐site synergy, high molecular weight (Mn > 100 kg/mol) CO2‐based copolymers with CU among 50%—90% were successfully synthesized and their properties were firstly investigated. This work not only contributes to enriching the scope of the application of CO2‐based copolymers but also provides a new platform for the development of a new generation of catalysts. [ABSTRACT FROM AUTHOR]

Polyhydroxyalkanoates (PHAs) are polyesters synthesized as a carbon and energy reserve material by a wide number of bacteria. These polymers are characterized by their thermoplastic properties similar to those of plastics derived from the petrochemical industry, such as polyethylene and polypropylene. PHAs are widely used in the medical field and have the potential to be used in other applications due to their biocompatibility and biodegradability. Among PHAs, P(3HB-co-3HV) copolymers are thermo-elastomeric polyesters that are typically soft and flexible with low to no crystallinity, which can expand the range of applications of these bioplastics. Several bacterial species, such as Cupriavidus necator, Azotobacter vinelandii, Halomonas sp. and Bacillus megaterium, have been successfully used for P(3HB-co-3HV) production, both in batch and fed-batch cultures using different low-cost substrates, such as vegetable and fruit waste. Nevertheless, in recent years, several fermentation strategies using other microbial models, such as methanotrophic bacterial strains as well as halophilic bacteria, have been developed in order to improve PHA production in cultivation conditions that are easily implemented on a large scale. This review aims to summarize the recent trends in the production and recovery of PHA copolymers by fermentation, including different cultivation modalities, low-cost raw materials, as well as downstream strategies that have recently been developed with the purpose of producing copolymers, such as P(3HB-co-3HV), with suitable mechanical properties for applications in the biomedical field. [ABSTRACT FROM AUTHOR]

The development of polymer carriers for systems of prolonged and controlled release of substances, particularly drugs, into the action environment is a relevant task in polymer chemistry and technology. This aims to solve the problem of reducing the effective dose of a medical drug administered into the body of a person or animal. The latest achievements in the field of creating such carriers in the form of spherical particles based on 2- hydroxyethyl methacrylate and polyvinylpyrrolidone (co)polymers are analyzed and summarized. The working principles and advantages of such systems are described. The research of the synthesis regularities, structure, properties and perspectives of application of granular hydrogels based on 2-hydroxyethyl methacrylate and its copolymers with polyvinylpyrrolidone was analyzed. The mixture of decanol and cyclohexanol as a solvent for the monomer phase is substantiated. Based on the analysis of kinetic studies, the optimal technological parameters for the suspension polymerization of 2-hydroxyethyl methacrylate with polyvinylpyrrolidone were selected, and the possibility of regulating the dispersion characteristics of copolymers via changes in the technological synthesis modes was confirmed. The results of studies on the sorption-desorption properties of copolymers concerning model substances and drugs are described. The possibility of directed regulation of sorption capacity and drug release rate through changes in copolymer composition was confirmed. Methods for increasing the sorption capacity of hydrogels for drugs are proposed. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Converting CO2 into valuable chemicals is an effective means to alleviate environmental pressure and the depletion of oil resources. Among them, polymers derived from the copolymerization of PO and CO2 have been widely studied because of their excellent properties. To meet the expansion of the application range of CO2‐based polymers, regulation of the CU in the polymer is imperative. Based on the understanding of the relationship between catalyst synergy and structure, we designed a new generation of polyester‐based polymeric catalysts APEPC‐R and RPEPC‐N with discretely distributed active centers to achieve the synthesis of CO2‐based polymers with regulated CU (from 50% to 90%). The discrete arrangement of catalyst active centers was demonstrated by 1H NMR and UV‐vis characterization. Benefiting from multi‐site synergy, high molecular weight (Mn > 100 kg/mol) CO2‐based copolymers with CU among 50%—90% were successfully synthesized and their properties were firstly investigated. This work not only contributes to enriching the scope of the application of CO2‐based copolymers but also provides a new platform for the development of a new generation of catalysts. [ABSTRACT FROM AUTHOR]

Flexible sensors are in great demand in the field of wearable electronics because of their good softness, stretchability, breathability and structural elasticity. Besides, polyvinylidene fluoride (PVDF) and its copolymers have been considered as promising piezoelectric materials for advanced sensing and excellent biocompatibility. Electrospinning is simple, low cost, and scalable technology that can be used to fabricate PVDF-based nanofibers applied in long-term monitoring or human–computer interaction. In this paper, we initially presented the basic process for preparing PVDF nanofibers, followed by a systematic elaboration on extended electrospinning techniques to facilitate more in-depth research on PVDF-based nanofibers. Then, the enhancements methods were summarized, complemented by some reinforcing mechanisms, novel structures and some solutions for filler agglomeration. Furthermore, the latest applications as wearable sensors were introduced. Potential difficulties, problems and perspectives are also discussed. We hope that this article can help researchers better understand this field and push it to a higher level. [ABSTRACT FROM AUTHOR]

Two new copolymers (named PTO‐BO and PTO‐HD) with alkyloxime‐substituted thiophene (TO) as acceptor unit and 6‐undecylthiopheno[3,2‐b]thiophene spacer as π‐bridge were synthesized and applied in organic solar cells (OSCs) as electron donors. PTO‐HD with 2‐hexyldecyl side chains on TO moiety possesses more suitable phase separation, more efficient exciton dissociation and charge transportation, and less charge recombination than PTO‐BO with 2‐butyloctyloxime‐substituted thiophene in OSCs with Y6 as the acceptor. As a result, the OSCs based on PTO‐HD:Y6 achieved an optimal power conversion efficiency (PCE) of 13.89% with a Voc of 0.799 V, a Jsc of 22.74 mA cm−2, and a FF of 67.67% without additives, which is higher than that (12.29%) of PTO‐BO:Y6 OSCs. [ABSTRACT FROM AUTHOR]

This study presents, for the first time, a new method for the synthesis of polymers containing different ratios of oxidized quinoid and reduced benzenoid units in polyaniline (PANi)‐like structure. Copolymers were synthesized by an oxidative copolymerization method of p‐phenylene diamine (p‐PDA) and o‐anisidine (o‐An) in an organic medium using different initial compositions of monomers. The compositions of the copolymer were determined based on 1H NMR spectral data. The thermal stability, electrical conductivity, morphology, and solubility were studied and a comparative analysis with polyaniline and corresponding homopolymers was been carried out. The thermal behavior of copolymers was studied using thermogravimetric analysis and differential scanning calorimetry. It was found that during heating one endothermic process of water evaporation and two exothermic processes occur, which depend on copolymer composition, and only 30% weight loss occurs up to 600 °C. It is shown that room‐temperature conductivity of copolymers doped with hydrochloric and sulfuric acids ranges from 10−5 to 10−3 S cm−1 and increases with increasing concentration of o‐anisidine structural units. The conductivity of iodine‐doped copolymers is of the same order as the conductivity of iodine‐doped PANi in emeraldine and leucoemeraldine forms. The morphology of doped copolymers depends on the co‐monomer ratio and the type of dopants. [ABSTRACT FROM AUTHOR]

The urgent need to mitigate climate change has spurred research into innovative carbon dioxide (CO2) capture materials. In this study, the design and synthesis of CO2‐responsive diblock copolymers, poly (N‐[3‐(dimethylamino)propyl]‐acrylamide)‐b‐poly(methyl methacrylate) (PDMAPAm‐b‐PMMA) are focused on via a two‐step reversible addition−fragmentation chain‐transfer (RAFT) polymerization as well as the application of the synthesized diblock copolymer as a membrane for CO2 capture. The resulting diblock copolymer possesses distinct blocks with varying properties. The poly (N‐[3‐(dimethylamino)propyl]‐acrylamide) (PDMAPAm) block provides CO2‐responsive behavior, while the poly(methyl methacrylate) (PMMA) block contributes to mechanical stability. The gas transport properties of the fabricated thin‐film composite membrane made of PDMAPAm‐b‐PMMA are measured. It is determined that the copolymer exhibits dual responsiveness towards CO2 and can be tailored for use in fabrication of membranes for direct air capture (DAC). [ABSTRACT FROM AUTHOR]

Conducting polymers are emerging as promising alternatives to rare and expensive platinum for counter electrodes in dye-sensitized solar cells; due to their ease of synthesis, they can be chemically tuned and are suitable for roll-to-roll production. Among these, poly (3,4-ethylenedioxythiophene) (PEDOT)-based counter electrodes have shown leading photovoltaic performance. However, certain conductivity issues remain that affect the effectiveness of these counter electrodes. In this study, we present an electropolymerized PEDOT and poly(N-alkylated-carbazole) copolymer as an efficient electrocatalyst for the reduction in I 3 − in dye-sensitized solar cells. Copolymerization with N-alkylated carbazoles significantly increases the conductivity of the polymer film and facilitates rapid charge transport at the interface between the polymer electrode and the electrolyte. The length of the alkyl substituents also plays a crucial role in this improvement. Electrochemical analysis showed a reduction in charge transport resistance from 3.31 Ω·cm2 for PEDOT to 2.26 Ω·cm2 for the PEDOT:poly(N-octylcarbazole) copolymer, which is almost half the resistance of a platinum-based counter electrode (4.12 Ω·cm2). Photovoltaic measurements showed that the solar cell with the PEDOT:poly(N-octylcarbazole) counter electrode achieved an efficiency of 8.88%, outperforming both PEDOT (7.90%) and platinum-based devices (7.57%). [ABSTRACT FROM AUTHOR]

This review article delves into the intriguing phenomenon of low-temperature thermochromism, whereby materials change color in response to temperature variations, with a particular focus on its applications in temperature-sensitive fields like medical storage. By closely examining thermochromic materials, this article highlights their potential to offer innovative solutions for monitoring and preserving thermolabile products that require strict temperature control. This leads to a special emphasis on polydiacetylenes (PDAs), a class of conjugated polymers with unique low-temperature thermochromic properties, positioning them as promising candidates for reliable temperature indicators. This article then explores the underlying mechanisms for fine-tuning the thermochromic behavior of PDAs, particularly discussing recent advancements in PDA design, such as structural alterations of monomers to achieve low-temperature thermochromism. These modifications, influenced by factors like side-chain length, hydrogen-bonding interactions, and the use of copolymers, are intended to result in irreversible color transitions at specific low temperatures, which is crucial to maintaining the integrity of thermally sensitive products. Finally, this article discusses the potential applications of PDAs as thermochromic sensors in tissue biobanking, where their ability to provide visual indications of temperature fluctuations could significantly enhance the monitoring and management of biological samples. [ABSTRACT FROM AUTHOR]

Thermoplastic elastomers (TPEs) based on styrenic block copolymers constitute excellent examples of self‐networking macromolecules that are employed in a wide range of contemporary technologies as molded parts. In such applications, these TPEs exist as dense (nonporous) films or other shapes. Here, it is first demonstrated that a series of commercial TPEs possessing comparable compositions can be electrospun from solution to form microfibers that are arranged into nonwoven mats that are breathable. An important consideration for microfiber formation is the copolymer molecular weight, which regulates i) the viscosity of the parent solution prior to electrospinning, ii) the ability of these copolymers to self‐assemble during electrospinning, iii) the microfiber morphology, and iv) the mechanical properties of the resultant microfibers. The addition of a midblock‐selective aliphatic oil to these TPEs yields thermoplastic elastomer gels (TPEGs), wherein the copolymer morphology and mechanical properties become highly composition‐tunable. Electrospinning TPEGs from a binary oil+solvent solution introduces a micelle inversion mechanism that begins with an oil‐rich micellar core and ends with a styrene‐rich micellar core, required for network stabilization, as the solvent dries during microfiber solidification. This work has implications for the production of controllably low‐modulus microfibrous materials possessing modestly improved toughness but exceptional extensibility and enhanced optical transparency. [ABSTRACT FROM AUTHOR]

Polymer cubosomes (PCs) are a recent class of self‐assembled nanostructures with great application potential due to their high porosity and surface area. Currently, most reported PCs consist of polystyrene block copolymers (BCPs), for which self‐assembly parameters are rather well understood. Changing the block chemistry would be desirable to introduce more functionality; however, knowledge of adapting the self‐assembly process to new chemistries remains limited. This work, reports on synthesizing poly(ethylene oxide)‐block‐poly(4‐acetoxystyrene) and its copolymers with styrene, and provide conditions for their self‐assembly into PCs with high yield and high inner order. It is shown that the polarity of the starting solvent toward the corona block allows tuning of the final morphology by controlling the corona volume and packing parameter. [ABSTRACT FROM AUTHOR]

The structure‐properties relationships of sustainable materials derived from biomass‐based monomers are investigated, focusing on hybrid styrene/terpene‐based copolymers with blocky microstructures, such as β‐myrcene– and β‐ocimene–styrene copolymers. The samples show complex glass transition dynamics, as evidenced by the physical aging experienced by the amorphous phase in styrene‐rich copolymers. The tendency of styrene‐ and terpene‐rich sequences to give heterogeneous morphologies with correlation strength extending over 10–40 nm is outlined, through small‐angle X‐ray scattering analysis. A new class of terpene‐based hybrid systems, holding promise for applications in surface coating technologies, is identified. [ABSTRACT FROM AUTHOR]

Alternating copolymers are crucial for diverse applications. While dispersity (Ð, also known as molecular weight distribution, MWD) influences the properties of polymers, achieving low dispersities in alternating copolymers poses a notable challenge via free radical polymerizations (FRPs). In this work, we demonstrated an unexpected discovery that dispersities are affected by the participation of charge transfer complexes (CTCs) formed between monomer pairs during free radical alternating copolymerization, which have inspired the successful synthesis of various alternating copolymers with low dispersities (>30 examples, Ð=1.13–1.39) under visible‐light irradiation. The synthetic method is compatible with binary, ternary and quaternary alternating copolymerizations and is expandable for both fluorinated and non‐fluorinated monomer pairs. DFT calculations combined with model experiments indicated that CTC‐absent reaction exhibits higher propagation rates and affords fewer radical terminations, which could contribute to low dispersities. Based on the integration of Monte Carlo simulation and Bayesian optimization, we established the relationship map between FRP parameter space and dispersity, further suggested the correlation between low dispersities and higher propagation rates. Our research sheds light on dispersity control via FRPs and creates a novel platform to investigate polymer dispersity through machine learning. [ABSTRACT FROM AUTHOR]

Circularly polarized luminesce (CPL) materials are crucial for various applications, including display devices and bionics. However, existing CPL materials face difficulties in simultaneously meeting large luminescence asymmetry factors (glum), high photoluminescence quantum yields (PQY), and long lifetime. Here, a simple strategy to prepare a series of high‐performance CPL liquid crystal copolymers is constructed by triplet–singlet Förster‐resonance energy transfer (TS‐FRET). A series of chiral liquid crystal copolymers are successfully synthesized by copolymerizing phosphorescent donor bearing chiral cholesterol mesogen with fluorescence acceptor bearing naphthalimide chromophore. The introduction of the naphthalimide component promotes the formation of twist grain boundary smectic‐A phase (TGBA*) and behaves distinctive selective reflective effect. An effective TS‐FRET process occurs in the two components of copolymers, and dual emission characteristics of thermally activated delayed fluorescence and room‐temperature phosphorescence are observed in the copolymer films. When the naphthalimide content of copolymer is 10%, the luminescence lifetime can achieve 83.0 ms. As the naphthalimide content increases, the glum initially increases and subsequently decreases, reaching a maximum of −1.15. In addition, the copolymer films possess enhanced photoluminescence quantum yield by TS‐FRET with a maximum value of 68%. The application of copolymers in information security is also explored. [ABSTRACT FROM AUTHOR]

Low‐band gap semiconductor polymer materials play a crucial role in the field of organic optoelectronics. In this context, a series of low‐band gap polymers containing thienopyrazine as the acceptor and cyclofluorene–bithiophene as the donor were synthesized and utilized in resistive random access memory (RRAM) devices. These memory devices consistently exhibit nonvolatile flash memory behavior. Remarkably, all three polymers demonstrate stability even after 1000 cycles without significant fluctuations. Notably, the three polymer‐based devices also exhibit excellent ternary memory performance, with current ratios of 1:102.8:104, 1:101.3:103.9, and 1:101.8:103.6. Furthermore, the photoelectric properties of the three polymers and the conduction mechanisms of the memory devices were thoroughly discussed. [ABSTRACT FROM AUTHOR]

The anion exchange membrane (AEM) suffered from poor mechanical properties and low ionic conductivity in fuel cells. Herein, a series of novel block fluorene‐contained poly(arylene ether ketone)s backbones are synthesized by a tandem one‐pot process and then grafted with alkyl chains to form comb‐shaped structure for preparing AEMs. The one‐pot synthesis of block copolymer avoids the multiple purifications of oligomers. The membranes' structure–property relationship is studied by changing the ratios of hydrophilic and hydrophobic segments. The designed comb‐shaped structures grafted on fluorene‐containing block backbones can widen the space between chains and form clear microphase separation patterns, as determined by atomic force microscope (AFM) and small angle x‐ray scattering (SAXS). Hence, resulting AEMs have a high ionic conductivity (117.4 mS cm−1, 80°C). Meanwhile, they also present low swelling rate (SR) from 12.76% to 18.51% at 30°C, 16.84% to 24.36% at 60°C, and 18.33% to 25.81% at 80°C. In addition, excellent mechanical properties, that is, an elongation at break of 29.63% and a tensile strength of 28.72 MPa, are achieved and showed the promise of as‐fabricated AEMs in fuel cell applications. [ABSTRACT FROM AUTHOR]

Poly(lactate-co-3-hydroxybutyrate) [P(LA-co-3HB)] is a high-molecular-weight biomaterial with excellent biocompatibility and biodegradability. In this study, the properties of P(LA-co-3HB) were examined and found to be affected by its lactate fraction. The efficiency of lactyl-CoA biosynthesis from intracellular lactate significantly affected the microbial synthesis of P(LA-co-3HB). Two CoA transferases from Anaerotignum lactatifermentans and Bacillota bacterium were selected for use in copolymer biosynthesis from 11 candidates. We found that cotAl enhanced the lactate fraction by 31.56% compared to that of the frequently used modified form of propionyl-CoA transferase from Anaerotignum propionicum. In addition, utilizing xylose as a favorable carbon source and blocking the lactate degradation pathway further enhanced the lactate fraction to 30.42 mol% and 52.84 mol%, respectively. Furthermore, when a 5 L bioreactor was used for fermentation utilizing xylose as a carbon source, the engineered strain produced 60.60 wt% P(46.40 mol% LA-co-3HB), which was similar to the results of our flask experiments. Our results indicate that the application of new CoA transferases has great potential for the biosynthesis of other lactate-based copolymers. [ABSTRACT FROM AUTHOR]

Polyallenes with appropriate pendants can form stable helices and exhibit significant optical activity. These helical polyallenes contain reactive double bonds that allow for further functionalization, making them a class of chiral functional materials with broad application prospects. This review article delves into the intricacies of synthesizing well‐defined helical polyallenes through controlled synthetic methodologies, including helix‐sense selective living polymerization, regioselective and asymmetric living polymerization, and one‐pot block copolymerization of allenes with aryl monomers. The systemically outlined characteristics of the resulting helical polyallenes and related copolymers are summarized include their unique chiroptical properties, stimuli‐responsiveness, helix‐induced chiral self‐assembly, and circularly polarized luminescence (CPL). Additionally, current challenges and future perspectives in the research of controlled synthesis, functionalities, and applications of helical polyallenes are discussed in detail. [ABSTRACT FROM AUTHOR]

Self‐assembled networks of bottlebrush copolymers are promising materials for biomedical applications due to a unique combination of ultra‐softness and strain‐adaptive stiffening, characteristic of soft biological tissues. Transitioning from ABA linear‐brush‐linear triblock copolymers to A‐g‐B bottlebrush graft copolymer architectures allows significant increasing the mechanical strength of thermoplastic elastomers. Using real‐time synchrotron small‐angle X‐ray scattering, it is shown that annealing of A‐g‐B elastomers in a selective solvent for the linear A blocks allows for substantial network reconfiguration, resulting in an increase of both the A domain size and the distance between the domains. The corresponding increases in the aggregation number and extension of bottlebrush strands lead to a significant increase of the strain‐stiffening parameter up to 0.7, approaching values characteristic of the brain and skin tissues. Network reconfiguration without disassembly is an efficient approach to adjusting the mechanical performance of tissue‐mimetic materials to meet the needs of diverse biomedical applications. [ABSTRACT FROM AUTHOR]

Photo‐triggering curing coatings have advantages of improving production efficiency, reducing pollution emissions, and contributing to green environmental protection. However, making the trade‐off between appropriate viscosity and UV‐curing properties in a high‐performing polymer system remains a formidable challenge. In this paper, firstly, a series of acrylate copolymer oligomers (named as PAAR) were synthesized using methyl methacrylate (MMA), butyl acrylate (BA), and glycidyl methacrylate (GMA), then methacrylic acid (MAA) was grafted utilizing the reaction between carboxyl group in MAA with epoxy group in oligomer to introduce double bonds. By adjusting the oligomer molecular weight to control the viscosity and changing the GMA ratio to obtain suitable double bonds content. As a result, the number molecular weight (Mn) of the thus‐obtained PAAR oligomers were less than 3000 Da, and the polymer dispersity indexes (PDI) were lower than 1.8. Photo‐polymerization kinetics revealed that the coating prepared using the oligomers could be fully cross‐linked by UV light triggering within 60 s, achieving a high transparency of 90% along with favorable thermal and mechanical properties. Furthermore, it was confirmed that the water resistance on the surface of the cured films and hydrophobicity were more influenced by the presence of hydroxyl groups. [ABSTRACT FROM AUTHOR]