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We employ polymer integral equation theory to study a simplified model of semiflexible polymerized ionic liquids (PolyILs) that interact via hard core repulsions and short range screened Coulomb interactions. The multi-scale structure in real and Fourier space of PolyILs (ions chosen to mimic Li, Na, K, Br, PF6, and TFSI) are determined as a function of melt density, Coulomb interaction strength, and ion size. Comparisons with a homopolymer melt, a neutral polymer–solvent-like athermal mixture, and an atomic ionic liquid are carried out to elucidate the distinct manner that ions mediate changes of polymer packing, the role of excluded volume effects, and the influence of chain connectivity, respectively. The effect of Coulomb strength depends in a rich manner on ion size and density, reflecting the interplay of steric packing, ion adsorption, and charge layering. Ion-mediated bridging of monomers is found, which intensifies for larger ions. Intermediate range charge layering correlations are characterized by a many-body screening length that grows with PolyIL density, cooling, and Coulomb strength, in disagreement with Debye–Hückel theory, but in accord with experiments. Qualitative differences in the collective structure, including an ion-size-dependent bifurcation of the polymer structure factor peak and pair correlation function, are predicted. The monomer cage order parameter increases significantly, but its collective ion counterpart decreases, as ions become smaller. Such behaviors allow one to categorize PolyILs into two broad classes of small and large ions. Dynamical implications of the predicted structural results are qualitatively discussed. [ABSTRACT FROM AUTHOR]

Designing homogeneous networks is considered one typical strategy for solving the problem of strength and toughness conflict of polymer network materials. Experimentalists have proposed the hypothesis of obtaining a structurally homogeneous hydrogel by crosslinking tetra-armed polymers, whose homogeneity was claimed to be verified by scattering characterization and other methods. Nevertheless, it is highly desirable to further evaluate this issue from other perspectives. In this study, a coarse-grained molecular dynamics simulation coupled with a stochastic reaction model is applied to reveal the topological structure of a polymer network synthesized by tetra-armed monomers as precursors. Two different scenarios, distinguished by whether internal cross-linking is allowed, are considered. We introduce the Dijkstra algorithm from graph theory to precisely characterize the network structure. The microscopic features of the network structure, e.g., loop size, dispersity, and size distribution, are obtained via the Dijkstra algorithm. By comparing the two reaction scenarios, Scenario II exhibits an overall more idealized structure. Our results demonstrate the feasibility of the Dijkstra algorithm for precisely characterizing the polymer network structure. We expect this work will provide a new insight for the evaluation and description of gel networks and further help to reveal the dynamic process of network formation. [ABSTRACT FROM AUTHOR]

Loop formation in complex environments is crucially important to many biological processes in life. In the present work, we adopt three-dimensional Langevin dynamics simulations to investigate passive and active polymer looping kinetics in crowded media featuring polymer–crowder attraction. We find polymers undergo a remarkable coil–globule–coil transition, highlighted by a marked change in the Flory scaling exponent of the gyration radius. Meanwhile, looping time as a function of the crowder's volume fraction demonstrates an apparent non-monotonic alteration. A small number of crowders induce a compact structure, which largely facilitates the looping process. While a large number of crowders heavily impede end-to-end diffusion, looping kinetics is greatly inhibited. For a self-propelled chain, we find that the attractive crowding triggers an unusual activity effect on looping kinetics. Once a globular state is formed, activity takes an effort to open the chain from the compact structure, leading to an unexpected activity-induced inhibition of looping. If the chain maintains a coil state, the dominant role of activity is to enhance diffusivity and, thus, speed up looping kinetics. The novel conformational change and looping kinetics of both passive and active polymers in the presence of attractive crowding highlight a rather distinct scenario that has no analogy in a repulsive crowding counterpart. The underlying mechanism enriches our understanding of the crucial role of attractive interactions in modulating polymer structure and dynamics. [ABSTRACT FROM AUTHOR]

We propose a method to build full-atomistic (FA) amorphous polymer structures using reverse-mapping from coarse-grained (CG) models. In this method, three models with different resolutions are utilized, namely the CG1, CG2, and FA models. It is assumed that the CG1 model is more abstract than the CG2 model. The CG1 is utilized to equilibrate the system, and then sequential reverse-mapping procedures from the CG1 to the CG2 models and from the CG2 to the FA models are conducted. A mapping relation between the CG1 and the FA models is necessary to generate a polymer structure with a given density and radius of chains. Actually, we have used the Kremer–Grest (KG) model as the CG1 and the monomer-level CG model as the CG2 model. Utilizing the mapping relation, we have developed a scheme that constructs an FA polymer model from the KG model. In the scheme, the KG model, the monomer level CG model, and the FA model are successively constructed. The scheme is applied to polyethylene (PE), cis 1,4-polybutadiene (PB), and poly(methyl methacrylate) (PMMA). As a validation, the structures of PE and PB constructed by the scheme were carefully checked through comparison with those obtained using long-time FA molecular dynamics (MD) simulations. We found that both short- and long-range chain structures constructed by the scheme reproduced those obtained by the FA MD simulations. Then, as an interesting application, the scheme is applied to generate an entangled PMMA structure. The results showed that the scheme provides an efficient and easy way to construct amorphous structures of FA polymers. [ABSTRACT FROM AUTHOR]

In this work, we compare the single chain dynamic structure factors for five different polymers: polyolefins (PE and PEP), poly-dienes (PB and PI), and a polyether (PEO). For this purpose, we have extended the De Gennes approximation for the dynamic structure factor. We describe the single chain dynamic structure factor in multiplying the coherent scattering functions for local reptation and Rouse motion within the Rouse blob. Important results are (i) the simple De Gennes structure factor S(Q, t)DG approximates within a few Å the outcome for the tube diameter of the more elaborate structure factor (exception PI); (ii) the extended De Gennes structure factor together with the Rouse blob describes the neutron spin echo spectra from the different polymers over the complete momentum transfer range and the full time regime from early Rouse motion to local reptation; and (iii) the representation of the scattering functions could significantly be improved by introducing non-Gaussianity corrections to the Rouse-blob dynamics. (iv) The microscopic tube step length in all cases is significantly larger than the rheological one; further tweaking the relation between tube length and entanglement blob size may indicate a possible trend toward an anisotropic lean tube with a step-length larger than the lateral extension. (v) All considered polymer data coincide after proper (Q, t) scaling to a universal behavior according to the length scale of the tube, while the relevant time scale is the entanglement time τe. (vi) In terms of the packing model, the required number of chains spanning the entanglement volume consistently is about 40% larger than that obtained from rheology. [ABSTRACT FROM AUTHOR]

Phase change materials (PCM) often encounter severe problems of leakage and shape collapse concerns. Chemical modification methods, utilizing chemical bonds to bind phase change molecular chains, have the potential to address the above‐mentioned problems radically. However, this approach often entails the use of expensive raw materials and complex processes. Therefore, a simple one‐pot preparation method had been reported using earth‐abundant and inexpensive octadecyl methacrylate (OMA) and 1,6‐hexanediol diacrylate (HD) as raw materials to prepare PCM with a molecular structure of cross‐linked polymer main chains and phase change side chains through free radical polymerization. Owing to the three‐dimensional polymer main chain structure, it exhibited excellent leakage‐proof performance, maintaining its form‐stable nature at 70°C with no obvious leakage observed during the phase change process, confirming it to be an excellent intrinsic solid–solid PCM (SSPCM). Additionally, the introduction of the cross linking segment significantly improves its thermal stability, and the 50% degradation temperature increased significantly from 228.8 to 355.9°C. Moreover, the latent heat increased with the decrease of the crosslinking density until the molar ratio of HD/OMA was reduced to 1/40 and then tended to reach constant. At the optimal ratio the latent heat of SSPCM can reach 88.23 J g−1. Excessive crosslinking density will affect the stacking tightness of molecular chains during the crystallization process, thereby reducing the latent heat. [ABSTRACT FROM AUTHOR]

Highlights Artificial intelligence (AI) techniques are increasingly used for structural health monitoring (SHM) of polymer composite structures. However, to be confident in the trustworthiness of AI models, the models must be reliable, interpretable, and explainable. The use of explainable artificial intelligence (XAI) is critical to ensure that the AI model is transparent in the decision‐making process and that the predictions it provides can be trusted and understood by users. However, existing SHM methods for polymer composite structures lack explainability and transparency, and therefore reliable damage detection. Therefore, an interpretable deep learning model based on an explainable vision transformer (X‐ViT) is proposed for the SHM of composites, leading to improved repair planning, maintenance, and performance. The proposed approach has been validated on carbon fiber reinforced polymers (CFRP) composites with multiple health states. The X‐ViT model exhibited better damage detection performance compared to existing popular methods. Moreover, the X‐ViT approach effectively highlighted the area of interest related to the prediction of each health condition in composites through the patch attention aggregation process, emphasizing their influence on the decision‐making process. Consequently, integrating the ViT‐based explainable deep‐learning model into the SHM of polymer composites provided improved diagnostics along with increased transparency and reliability. Autonomous damage detection of polymer composites using vision transformer based deep learning model. Explainable artificial intelligence by highlighting region of interest using patch attention. Comparison with the existing state of the art structural health monitoring methods. [ABSTRACT FROM AUTHOR]

Surface covalent modification of black phosphorus (BP) with organic polymers represents a promising strategy to enhance its stability and tailor its electronic properties. Despite this potential, developing memristive materials through suitable polymer structures, grafting pathways, and polymerization techniques remains challenging. In this study, polyaniline (PANI)‐covalently grafted black phosphorus nanosheets (BPNS) are successfully prepared with redox functionalities via the in situ polymerization of aniline on the surface of 4‐aminobenzene‐modified BPNS. The PANI coating protects the BP from direct exposure to oxygen and water, and it endows the material with analog memristive properties, characterized by a continuously adjustable resistance within a limited voltage scan range. When subjected to a broader voltage scan, the Al/PANI‐g‐BPNS/ITO device demonstrates a typical bistable digital memristive behavior. The integration of both digital and analog memristive functionalities in a single device paves the way for the development of high‐density, multifunctional electronic components. [ABSTRACT FROM AUTHOR]

Structural health monitoring is vital for improving the safety and reliability of fiber‐reinforced composites. However, it is still challenging to achieve high sensing performance without changing the overall properties of composites. In this work, conductive fibers were braided into pigtails to achieve high sensing sensitivity and maintain low electrical resistance. Conductive pigtails with hierarchical and critically connected percolation networks were integrated with basalt fabric by an embroidery technique to realize self‐diagnosis of composites. After being embedded in epoxy composites, the material exhibited low electrical resistance (128.8 kΩ) and excellent sensing performance, demonstrating a high Gauge factor of 8.1, good linearity (R2 > 99%) and stability. The experimental results also showed that conductive pigtails can sensitively inform crack initiation and growth inside composites, which is extremely important for warning of the risk of material fractures. In addition, the mechanical strength of the material was almost unchanged before and after the pigtails were embedded. All these results indicate that conductive pigtails could be used as highly sensitive sensors for realizing structural health monitoring in fiber‐reinforced composites. Highlights: CBs/TPU pigtails with hierarchical conductive paths were fabricated and firmly integrated with basalt fabric by the embroidery technique.There is a good interface between the pigtails and the matrix, resulting in the embedding of the pigtails with little change in the mechanical properties of the composites.Pigtails can sensitively detect crack initiation and growth in composites, demonstrating the potential for self‐diagnosis of fiber‐reinforced composites. [ABSTRACT FROM AUTHOR]

We present a new simple approach for electrochemical synthesis of semi-condensed ambipolar perinone polymers with phthaloperine (p1) or phenanthroline (p2) skeleton from available and cheap perimidine precursors. Polymerization of perimidine derivatives varies in efficiency depending on the monomer, but overall is highly efficient, especially when electropolymerization is used. Electrooxidation is well controllable and provides a certain characteristic share of new bonds in the structure of perimidine polymers: semi-ladder bis-perimidine unit, ladder bis-perimidine unit, and protonated bis-perimidine unit. Polymer p2 obtained with higher efficiency was put through broader analysis (UV–Vis, IR, ESR and quantum-chemical calculations). As indicated, donor–acceptor structure and specific intermolecular interactions of p2 assure its electrical conductivity and complex redox activity. Although protonated bonds break π-conjugation in the structure of the macromolecule, there is also a diradical state that favors intermolecular interactions and intermolecular π-conjugation channels within bis-perimidine segments. It has been proven that there is a diradical state which appears as an intermediate state between the oxidized and reduced states of the protonated polymer unit. This work positions perimidine polymers as a versatile ambipolar multiredox p- and n-type conductor, indicating a potential for expanding perinone-based perylene-diperimidine polymers for innovative electronics and (bio)sensors. [ABSTRACT FROM AUTHOR]

The significant interfacial resistance between solid electrolyte‐electrode interfaces is a major bottleneck for the practical application of solid‐state lithium batteries. This resistance is primarily caused by the formation of space charge layers (SCLs), resulting from the redistribution of ionic carriers at the interface between dissimilar materials with varying chemical potentials, which lead to insufficient carriers and sluggish lithium‐ion transport. In this study, a conjugated structure polymer is constructed through in situ polymerization onto the oxide electrolyte, forming charge‐rich SCLs on the organic/inorganic interface, and enabling the interfacial layer to maintain superior ion transfer and contact. The Li solid NMR spectra and computational study suggest that optimized SCLs offer effective pathways for Li+ conduction in the electrolyte, thereby enhancing the interfacial conduction. Furthermore, the designed electrolyte induces the formation of an inorganic‐rich interphase layer on the lithium anode, enabling rapid lithium‐ion transport and uniform Li deposition. Consequently, the lithium symmetric cell with this electrolyte operates for more than 5100 h, while LiFePO4/Li solid‐state batteries can stably cycle up to 800 times at 5 C. This interfacial modification strategy provides a new perspective for the rational design of the charge‐rich SCLs and advances the understanding of the SCLs inside the electrolyte. [ABSTRACT FROM AUTHOR]

Temperature‐responsive hydrogels, or thermogels, have emerged as a leading platform for sustained delivery of both small molecule drugs and macromolecular biologic therapeutics. Although thermogel properties can be modulated by varying the polymer's hydrophilic‐hydrophobic balance, molecular weight and degree of branching, varying the supramolecular donor‐acceptor interactions on the polymer remains surprisingly overlooked. Herein, to study the influence of enhanced hydrogen bonding on thermogelation, we synthesized a family of amphiphilic polymers containing urea and urethane linkages using quinuclidine as an organocatalyst. Our findings showed that the presence of strongly hydrogen bonding urea linkages significantly enhanced polymer hydration in water, in turn affecting hierarchical polymer self‐assembly and macroscopic gel properties such as sol‐gel phase transition temperature and gel stiffness. Additionally, analysis of the sustained release profiles of Aflibercept, an FDA‐approved protein biologic for anti‐angiogenic treatment, showed that urea bonds on the thermogel were able to significantly alter the drug release mechanism and kinetics compared to usage of polyurethane gels of similar composition and molecular weight. Our findings demonstrate the unrealized possibility of modulating gel properties and outcomes of sustained drug delivery through judicious variation of hydrogen bonding motifs on the polymer structure. [ABSTRACT FROM AUTHOR]

Fused deposition modeling (FDM) and melt electrowriting (MEW) are techniques that use polymer fibers as building blocks for printing complex 3D structures, with fibers at the macroscopic and micrometer scale. Here, FDM and MEW are used to produce fibers of shape memory polymer at two different scales, and compare the performance of these fibers, in terms of shape fixity, shape recovery, and self‐healing properties. FDM and MEW are used for 4D printing of a shape memory polymer blend of thermoplastic poly(ε‐caprolactone) (30% by wt.) and a soft thermoplastic elastomer polyurethane (70% by wt.) at two different scales. The shape transformation from a programmed temporary state to the printed permanent shape in response to temperature as the stimuli imparts the 4D aspect to the printing. The mean fiber diameter of shape memory polymer produced by FDM and MEW is 340 and 40 µm, respectively. The manufactured fibers show an excellent shape fixity ratio (≈95%) and shape recovery properties (>84%). MEW fibers show a 1.5x faster recovery rate than FDM fibers due to the scaling effect. The excellent shape memory properties are complemented by self‐healing characteristics in the printed fibers. Additionally, MEW of a shape memory polymer is directly performed on a cylindrical collector to obtain tubular constructs which can potentially be used as stents for coronary or vascular applications. [ABSTRACT FROM AUTHOR]

The functionally graded composite structures with viscoelastic polymers inherits the excellent performance of functionally graded composites and also possesses large damping performance, which has broad application prospects in the aerospace and mechanical engineering fields. However, due to the complexity of the structure itself, there is limited literature available on its theoretical modeling for efficient solutions. To predict its dynamic performance, a simplified dynamic model of the functionally graded composite structures with viscoelastic polymers is established. This model takes into account the displacement transfer relationship between the functional graded composite layer and the viscoelastic polymer layer. The governing differential equations are obtained by applying the Navier method and complex modulus theory. These equations are then solved using the Rayleigh–Ritz method. The validity of the theoretical model is confirmed by comparing it with existing literature and the results obtained from ANSYS software. Additionally, the model that has been developed is used to analyze how the graded index and elastic modulus of the structure, as well as its geometric parameters, affect its vibration and damping characteristics. [ABSTRACT FROM AUTHOR]

Context: This work introduces a method for generating generalized structures of amorphous polymers using simulated polymerization and molecular dynamics equilibration, with a particular focus on amorphous polymers. The techniques and algorithms used in this method are described in the main text, and example input scripts are provided for the GMXPolymer code, which is based on the GROMACS molecular dynamics package. To demonstrate the efficacy of our method, we apply it to different glassy polymers exhibiting varying degrees of functionality, polarity, and rigidity. The reliability of the method is validated by comparing simulation results with experimental data in various structural and thermal properties, both of which show excellent agreement. Methods: This work implements the GMXPolymer simulated polymerization algorithm on the GROMACS program. GMXPolymer code controls the main polymerization loop. The energy minimizations and molecular dynamics simulations use the GROMACS program called by the GMXPolymer code. A new ITP file is generated when a new bond is formed, and the necessary additions to the ITP file are made to include new bonds, angles, and dihedrals. In preparing the ITP file of the monomer, the charge of the reactive atom must be modified before the code runs so that it is a correct value after bonding. [ABSTRACT FROM AUTHOR]

Conjugated polymers (CPs) are widely used as conductive materials in various applications, with their conductive properties adjustable through chemical doping. While doping enhances the thermoelectric properties of CPs due to improved main-chain transport, overdoping can distort the polymer structure, increasing energy disorder and impeding intrinsic electrical transport. This study explored how different dopants affect the structural integrity and electrical transport properties of CPs. We found that dopants vary in their impact on CP structure, consequently altering their electrical transport capabilities. Specifically, ferric chloride (FeCl3)-doped indacenodithiophene-co-benzothiadiazole (IDTBT) shows superior electrical transport properties to triethyloxonium hexachloroantimonate (OA)-doped IDTBT due to enhanced backbone planarity and rigidity, which facilitate carrier transport and lower energetic disorder. These results highlight the critical role of dopant selection in optimizing CPs for advanced applications, suggesting that strategic dopant choices can significantly refine the charge transport characteristics of CPs, paving the way for their industrialization. [ABSTRACT FROM AUTHOR]

Thiophene polymers have been widely used to selectively disperse semiconducting single-walled carbon nanotubes (sc-SWNTs). Important questions concern the influence of the solvent on the adsorbability and adsorption-conformation of such polymers, along with the relation between the thiophene polymer structure and selectivity to SWNTs. These concerns about the behaviour of poly(perylene diimide (PDI)-thiophene) have been addressed in this study via molecular dynamics simulation. It is observed that the polymer does not adsorb to SWNTs in a solvent with strong polarity and shows an effective adsorbability in a solvent with moderate polarity or non-polarity. Its selectivity turns from metallic SWNTs to semi-conducting SWNTs in a solvent with a decreasing polarity. In addition, the rigid part in the polymer backbone (PDI) enlarges adsorbability significantly, and the flexible part (two thiophene units) adjusts its adsorption conformation onto SWNTs, which offers the selectivity. The study offers theoretical clues for designing the structure of thiophene polymers with respect to SWNTs-extraction. [ABSTRACT FROM AUTHOR]

Graphene platelets (GPLs) exhibit outstanding mechanical and physical properties and therefore are employed as a reinforcement in advanced polymer composite structures. The purpose of this paper is to analyze the biaxial buckling of functionally graded graphene-reinforced sandwich plates with a soft orthotropic core. A new high-order three-layer theory is developed for the accurate modeling and analysis of the sandwich structure. The sandwich plate is divided into three layers including two face sheets and a core and a different third-order kinematic assumption is dedicated to each layer. The transverse flexibility of each layer as well as the displacements continuity at the interfaces are considered. Additionally, the continuity conditions and the conditions of zero transverse stresses in the whole structure are satisfied. The plate is subjected to a biaxial compressive loading and the governing equations are derived using the principle of minimum potential energy. Analytical solutions are presented for simply supported boundary conditions to obtain the critical buckling load. The influences of plate geometry and GPL properties on buckling load are investigated. The results obtained in specific cases are compared with the published results and the validity of the present results is confirmed. It can be drawn that the use of GPL increases the buckling load of graphene-reinforced sandwich plates. [ABSTRACT FROM AUTHOR]

This work presents the main stages of the technological process of processing fluoropolymers (a copolymer of tetrafluoroethylene with ethylene and polyvinylidene fluoride) into products and defines their key processing parameters. Using thermomechanical and thermogravimetric analysis, it was determined that the maximum and minimum processing temperatures of the investigated fluoropolymers are 2400 C and 4300 C for the copolymer of tetrafluoroethylene with ethylene, and 1500 C and 4200 C for polyvinylidene fluoride, respectively. The optimal processing temperature of the studied fluoropolymers was determined using an indirect method of examining the influence of this factor on the physical and mechanical properties of the polymers. It was established that the optimal processing temperature is 2700 C for the copolymer of tetrafluoroethylene with ethylene, and 1800 C for polyvinylidene fluoride. X-ray structural studies of the fluoropolymers confirmed the assumption that increasing their processing temperature within the studied intervals leads to improved physical and mechanical properties due to changes in the structure of the polymers (increased crystallinity). The optimal pressing pressure for the investigated fluoropolymers was determined through studies of their main physical and mechanical properties, and it was established to be 40 MPa for fluoropolymers based on the copolymer of tetrafluoroethylene with ethylene and polyvinylidene fluoride. [ABSTRACT FROM AUTHOR]

Modern society relies heavily on producing commercial and industrial plastics to improve the quality and quantity of our lives. However, increased fire risks threaten commercial operations and the potential impact of high‐performance electronic and transportation technologies that utilize polymeric materials. Despite significant monitoring and reduction of commonly used halogenated flame retardants, their worldwide usage still poses environmental hazards. Many non‐halogenated flame‐retardant compounds are viable additives for synthetic polymers; however, their incorporation often results in reduced composite homogeneity and mechanical strength. This review focuses on reactive flame retardants and the effect of polymer structure on inherent flame retardance in recent studies. The synthesis and characterization of polymeric systems (e.g. polyurethanes, polyamides, polyimides, polyesters and epoxy resins) are discussed in terms of structure–flame‐retardant performance using a complement of analytical tools, including thermogravimetric analysis, cone calorimetry, limiting oxygen index and UL 94 testing. These commercially important polymeric systems represent a broad compositional space for future adaptation and the discovery of increasingly modular polymeric materials with, while also contributing to the fundamental understanding of unique combinations of gas‐ and condensed‐phase mechanisms of flame retardance. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

With the advancement of society, the issue of oil pollution is escalating, therefore we propose a straightforward and efficient approach for fabricating fully biodegradable poly (lactic acid) (PLA)/poly (butylene adipate-co-terephthalate) (PBAT) foams with exceptional selective oil-absorption capabilities through the integration of melt blending and supercritical CO2 (scCO2) foaming techniques. The PLA90 foams, activated at 11 MPa and temperatures ranging from 105 ℃ to 110 ℃, exhibit an expansion ratio of 44 and a highly interconnected open-cell structure with an open-cell content exceeding 80%, effectively mitigating cell shrinkage occurrences. The 105 ℃-triggered PLA90 foam displays pronounced lipophilicity/hydrophobicity, accelerated oil-absorption kinetics, and elevated oil-absorption capacity. Specifically, the equilibrium absorption capacities for cyclohexane and silicone are 12.8 g/g and 20.1 g/g, respectively. Moreover, the maximum absorption capacity decline rate for silicone oil stands at a mere 13.4% over 10 absorption–desorption cycles. The findings presented in this study establish a theoretical framework and offer empirical evidence to support the development of fully biodegradable, high-performance, and reusable oil-absorption materials. [ABSTRACT FROM AUTHOR]

Urethane imide anhydride oligomers with terminal groups as anhydride groups were designed and synthesized using second‐order nonlinear optical chromophore molecule, bisphenol AF‐type diethylidene dianhydride, and toluene diisocyanate as monomers. Polyurethaneimide (PUI) second‐order nonlinear optical polymers with the structure of imide and amino ester chain segments were then synthesized by the polycondensation reaction between urethane imide anhydride oligomers and aromatic diamine monomers. The glass transition temperature (Tg) of PUI reached 186°C, and the 5% heat‐loss decomposition temperature was 320°C. The corona‐polarized PUI had an electro‐optic (EO) coefficient (γ33) of 82 pm/V tested by the reflection method. The loss of light transmission of the polymer waveguide prepared with PUI as electro‐optical material was 1.13 dB/cm at 1550 nm. Mach–Zehnder type polymer waveguide electro‐optical modulators have been prepared based on the properties of the electro‐optic material PUI. The fabricated polymer EO modulators had favorable electro‐optic modulation response performance for low‐frequency electrical signals. The good modulation characteristics of the manufactured electro‐optical modulators proved that the synthesized PUI was a waveguide polymer material with good comprehensive performance. Highlights: Electro‐optic fluorinated polyurethaneimide was synthesized.Polyurethaneimide as core material, polymer waveguide EO modulators were fabricated.The prepared modulators had good electro‐optic modulation performance. [ABSTRACT FROM AUTHOR]

A series of iridium‐polymer complexes containing bipyridonate moieties were synthesized. The high catalytic performance of the iridium‐polymer complex for the dehydrogenative oxidation of alcohols was demonstrated. Notably, the bipyridonate moiety in the polymer structure acts as a chemically non‐innocent "functional ligand", realizing the enhancement of dehydrogenation process. While numerous metal‐polymer catalysts have been reported so far, to our knowledge, introducing a "functional ligand" into a polymer chain that can operate cooperatively with transition metals by changing their structures during the catalytic processes is rare. The iridium‐polymer complex could be easily separated from the product and recovered by precipitation upon the addition of methanol after the catalytic reaction. Furthermore, the recovered catalyst could be reused without loss of catalytic efficiency at least ten times. [ABSTRACT FROM AUTHOR]

Conjugated polymers are emerging as competitive candidates for organic thermoelectrics (OTEs). However, to make the device truly pervasive, both p‐ and n‐type conjugated polymers are essential. Despite great efforts, no n‐type equivalents to the p‐type benchmark PEDOT:PSS exist to date mainly due to the low electrical conductivity (σ). Herein, a near‐amorphous n‐type conjugated polymer, namely pDFSe, is reported with high σ by achieving the synergy between charge transport and doping efficiency. The polymer pDFSe is synthesized based on an acceptor‐triad moiety of diketopyrrolopyrrole‐difluorobenzoselenadiazole‐diketopyrrolopyrrole (DFSe), which has the noncovalently‐fused‐ring structure to reinforce the backbone rigidity. Furthermore, an axisymmetric thiophene‐selenophene‐thiophene donor is introduced, which enables the formation of near‐amorphous microstructures. The above merits ensure good doping efficiency without scarifying efficient intrachain charge‐carrier transport. Thus, pDFSe‐based n‐type transistors exhibit high electron mobility up to 6.15 cm2 V−1 s−1, much higher than its reference polymer pDSe without the noncovalently‐fused‐ring structure (0.77 cm2 V−1 s−1). Further upon n‐doping, pDFSe demonstrates excellent σ of 62.6 S cm−1 and maximum power factor of 133.1 μW m−1 K−2, which are among the highest values reported for solution‐processed n‐type polymers. The results demonstrate the great potential of near‐amorphous n‐type conjugated polymers with noncovalently‐fused‐ring structure for the next‐generation OTEs. [ABSTRACT FROM AUTHOR]

Solid polymer electrolytes are promising electrolytes for safe and high‐energy‐density lithium metal batteries. However, traditional ether‐based polymer electrolytes are limited by their low lithium‐ion conductivity and narrow electrochemical window because of the well‐defined and intimated Li+‐oxygen binding topologies in the solvation structure. Herein, we proposed a new strategy to reduce the Li+‐polymer interaction and strengthen the anion‐polymer interaction by combining strong Li+‐O (ether) interactions, weak Li+‐O (ester) interactions with steric hindrance in polymer electrolytes. In this way, a polymer electrolyte with a high lithium ion transference number (0.80) and anion‐rich solvation structure is obtained. This polymer electrolyte possesses a wide electrochemical window (5.5 V versus Li/Li+) and compatibility with both Li metal anode and high‐voltage NCM cathode. Li||LiNi0.5Co0.2Mn0.3O2 full cells with middle‐high active material areal loading (~7.5 mg cm−2) can stably cycle at 4.5 V. This work provides new insight into the design of polymer electrolytes for high‐energy‐density lithium metal batteries through the regulation of ion‐dipole interactions. [ABSTRACT FROM AUTHOR]

Recent progress in conjugated polymer photocatalysts has opened avenues for enhancing photocatalytic hydrogen production (PHP) activity through structural design. This study highlights the impact of the acceptor-to-donor feed ratio on PHP activity in copolymers, influencing their energy level structures. Five conjugated porous polymers (CPPs) were synthesized by adjusting the acceptor-to-donor molar ratio. Notably, at a 2:1 acceptor-to-donor ratio, the polymer demonstrated a high hydrogen evolution rate (HER) of 61.9 mmol g−1 h−1 under full arc irradiation without co-catalysts and an apparent quantum yield (AQY) of 7.77% at 475 nm. However, further increasing the proportion of the donor unit in the copolymers decreases their HER. Experiments and theoretical simulation characterized that the feed ratios effectively tune the polymer's molecular structure, hydrophilicity, band gap, and the generation and transport efficiency of photo-induced charge carriers, ultimately affecting the hydrogen production kinetics and efficiency. This research demonstrates that tuning the band structure and chemical compositions of CPPs through statistical copolymerization significantly impacts their PHP activity. [Display omitted] • Conjugated porous polymers (CPPs) with donor-acceptor type were prepared as photocatalysts. • PProDOT-didecyl was used as the donor unit to tune the energy levels of the CPPs. • BS-4 shows an impressive hydrogen evolution rate of 61.9 mmol g−1 h−1 under full arc free of co-catalyst. • The optimum donor-to-acceptor ratio is crucial for improved photocatalytic activity. [ABSTRACT FROM AUTHOR]

A novel synthesis strategy for hierarchical polypyrrole nanopillar/silver nanoparticle arrays is designed and its application as an antibacterial surface and nonenzymatic H2O2 sensor is explored. The hierarchical structure is fabricated using a microporous membrane‐templated method by multiple steps. Using a polypyrrole nanopillar array as the matrix, silver nanoparticles can be uniformly reduced and stably anchored onto the nanopillar array by a redox reaction in a AgNO3 solution. The morphology, structural characteristics, conductivity, and reaction mechanisms of the composites are studied in detail. The incorporation of Ag nanoparticles not only significantly enhanced the antibacterial activity of the surface, but also contributed to the excellent ability to detect H2O2. This work provides a versatile approach to achieve the controlled fabrication of hierarchical metal‐conducting polymer composite structures and demonstrates them as promising multifunctional interfaces with antibacterial and sensing activity. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Porous organic polymers (POPs) have attracted great attention in past decades. Although diverse functional POPs have been developed, multistimuli‐responsive POPs with excellent aggregate‐state luminescence together with good chiroptical properties have rarely been reported. Herein, two pairs of Salen‐type enantiomeric POPs with multistimuli‐responsive luminescence and chiral features were designed and synthesized by facile polycondensation reactions between polyfunctional aggregation‐induced emission luminogen (AIEgen)‐containing salicylaldehyde derivatives and chiral diamines. With Salen units in polymer backbones as tetradentate ligands, a series of POP‐metal complexes were further prepared. The obtained POPs and metal complexes show good porosity, high thermal stability, and obvious circular dichroism signals. Moreover, benefiting from the coexistence of AIEgen and Salen units in polymer structures, these POPs exhibit excellent luminescence performance in aggregate states and tunable fluorescence behaviors in response to external stimuli of Zn2+ ion, mechanical forces, organic solvent, and acids. Due to the dynamic feature of Schiff base C=N bonds, the present POPs can efficiently undergo hydrolysis reactions under strong acidic conditions to reproduce the AIEgen‐ containing monomers, and such an acid‐induced degradation process can be directly visualized and dynamically monitored via fluorescence variation. These properties collectively make the POPs candidate materials for applications in heterogeneous asymmetric catalysis, fluorescence sensing, biomedicine, etc. [ABSTRACT FROM AUTHOR]

Phase change materials with high energy storage density and stable phase change temperature are ideal choices for personal thermal therapy and heat management. However, leakage and poor flexibility have long been bottlenecks in their application. Excellent latent heat performance and flexibility are crucial, especially in the thermal management of flexible wearable devices. In this study, a simple strategy was adopted to prepare a flexible polyurethane-based phase change material using a prepolymer method with polyethylene glycol (PEG) as the phase change material. Attributed to the cross-linked network structure in the polymer, the prepared phase change material exhibits excellent thermal stability and shape stability without leakage. Additionally, it shows relatively high latent heat and good flexibility. Based on these significant comprehensive properties, a performance-improved thermal wrist wrap was designed to achieve thermal therapy and efficient human heat management. This work provides insights into the rational design of flexible and shape-stable high latent heat phase change materials, demonstrating tremendous potential applications in wearable thermal management. [ABSTRACT FROM AUTHOR]

In the last century, the issue of "water reserves" has become a remarkably strategic topic in modern science and technology. In this context, water resource treatment and management systems are being developed in both agricultural and urban area scenarios. This can be achieved using superabsorbent polymers (SAPs), highly cross-linked hydrogels with three-dimensional, hydrophilic polymer structures capable of absorbing, swelling and retaining huge amounts of aqueous solutions. SAPs are able to respond to several external stimuli, such as temperature, pH, electric field, and solution composition and concentration. They can be used in many areas, from sensor technology to drug delivery, agriculture, firefighting applications, food, and the biomedical industry. In addition, new categories of functional SAP-based materials, mainly superabsorbent polymer composites, can also encapsulate fertilizers to efficiently provide the controlled release of both water and active compounds. Moreover, SAPs have great potential in wastewater treatment for the removal of harmful elements. In this respect, in the following review, the most promising and recent advances in the use of SAPs and composite SAPs as tools for the sustainable management and remediation of water resource are reviewed and discussed by identifying opportunities and drawbacks and highlighting new challenges and aims to inspire the research community. [ABSTRACT FROM AUTHOR]

In this paper, a temperature sensor based on a polymer–silica heterogeneous integrated Mach–Zehnder interferometer (MZI) structure is proposed. The MZI structure consists of a polymer waveguide arm and a doped silica waveguide arm. Due to the opposite thermal optical coefficients of polymers and silica, the hybrid integrated MZI structure enhances the temperature sensing characteristics. The direct coupling method and side coupling method are introduced to reduce the coupling loss of the device. The simulation results show that the side coupling structure has lower coupling loss and greater manufacturing tolerance compared to the direct coupling structure. The side coupling loss for PMMA material-based devices, NOA material-based devices, and SU-8 material-based devices is 0.104 dB, 0.294 dB, and 0.618 dB, respectively. The sensitivity (S) values of the three hybrid devices are −6.85 nm/K, −6.48 nm/K, and −2.30 nm/K, which are an order of magnitude higher than those of an all-polymer waveguide temperature sensor. We calculated the temperature responsivity (RT) (FSR→∞) of the three devices as 13.16 × 10−5 K, 32.20 × 10−5 K, and 20.20 × 10−5 K, suggesting that high thermo-optic coefficient polymer materials and the hybrid integration method have a promising application in the field of on-chip temperature sensing. [ABSTRACT FROM AUTHOR]

Polymer networks remain an essential class of soft materials. Despite their use in everyday materials, connecting the molecular structure of the network to its macroscopic properties remains an active area of research. Much current research is enabled by advances in modern polymer chemistry providing an unprecedented level of control over macromolecular structure. At the same time, renewed interest in self‐healing, dynamic, and/or adaptable materials continues to drive substantial interest in polymer network design. As part of a special issue focused on research performed in the Polymer Science and Engineering Department at the University of Massachusetts, Amherst, this review highlights connections between macromolecular structure of networks and observed mechanical properties as investigated by the Tew research group. [ABSTRACT FROM AUTHOR]

A micromechanical model considering the spherulite structure of semi‐crystalline polymers was established in this study. The micro stress–strain histories were captured by combining the constitutive equations and multi‐axial fatigue criterion. The continuous damage theory was employed to describe the degradation of material properties during cycle loading. Based on the proposed model, the effects of microstructure features, such as grain anisotropy, defects, and crystallinity, on the fatigue performance was examined under multi‐axial loading condition. The local material degradation and damage accumulation were then focused on to understand the underlying fatigue mechanisms with various microstructures. Meanwhile, the crack initiation site was precisely predicted and discussed. This research provides theoretical support for understanding the failure mechanisms of spherulitic semi‐crystalline polymers, deepening the understanding of associated microstructural characteristics and strengthening the anti‐fatigue design of semi‐crystalline polymers. [ABSTRACT FROM AUTHOR]

Topochemical polymerization is a highly promising and effective method for constructing complex three-dimensional structures and functionalized polymers. Herein, we present for the first time a topochemical reaction of diacetylene within a meticulously designed covalent organic framework (ZNUC-1). Our experimental results revealed that ZNUC-1 underwent a 1,4-addition reaction under thermal induction, forming an ene–yne-conjugated structure. [ABSTRACT FROM AUTHOR]

We present machine‐learning interatomic potentials (MLIPs) for simulations of Si–C–O–H compounds. The MLIPs are constructed from moment tensor potentials (MTPs) and were trained to a library of configurations that included polysiloxane structures, hypothetical crystalline and amorphous SiCOH structures, and trajectories of Si–C–O–H systems obtained via ab initio molecular dynamic (aiMD) simulations at elevated temperatures. Passive, active, and hybrid learning strategies were implemented to develop the MLIPs. The MLIPs reproduce vibrational properties of polymers and SiCOH structures obtained from aiMD simulations, thus providing a tool to identify chemical units and distinct structural characteristics through their vibrational properties. Simulations of the polymer‐to‐ceramic transformation show the development of mixed tetrahedra in SiCO ceramics and align with experimental observations. Million‐atom simulations for several nanoseconds highlight the precipitation of graphitic nanosheets from a carbon‐rich SiCO precursor. Atomistic simulations with the MLIPs deliver details of chemical reaction mechanisms during the pyrolysis of polysiloxanes, including methane abstraction and Kumada‐like rearrangements that transform the siloxane backbone. While the MLIPs still leave room for systematic improvement, they deliver simulations with “density functional theory (DFT)‐like” quality at low and high temperatures. [ABSTRACT FROM AUTHOR]

Nanostructuration of dynamic helical polymers such as poly(phenylacetylene)s (PPAs) depends on the secondary structure adopted by the polymer and the functional group used to connect the chiral pendant to the PPA backbone. Thus, while PPAs with dynamic and flexible scaffolds (para‐ and meta‐substituted, ω1<165°) generate by nanoprecipitation low polydisperse nanospheres with controllable size at different acetone/water mixtures, those with a quasi‐static behavior and the presence of an extended, almost planar structure (ortho‐substituted, ω1>165°), aggregate into a mixture of spherical and oval nanostructures whose size is not controlled. Photostability studies show that poly(phenylacetylene) particles are more stable to light irradiation than when dissolved macromolecularly. Moreover, the photostability of the particle depends on the secondary structure of the PPA and its screw sense excess. This fact, in combination with the encapsulation ability of these polymer particles, allows the creation of light stimuli‐responsive nanocarriers, whose cargo can be delivered by light irradiation. [ABSTRACT FROM AUTHOR]

The present study elucidates the role of annealing with electric field on lamellar crystalline structure and molecular orientation of polymer chains in ferroelectric copolymer (P(VDF‐TrFE)) and ferroelectric terpolymer (P(VDF‐TrFE‐CFE)) spin‐coated thin films. The ferroelectric polymer thin films annealed under an electric field support the growth of nanostructure with an “edge‐on” lamellar crystalline structure having in‐plane molecular chain orientation. The poled P(VDF‐TrFE) thin films have higher remnant polarization (Pr) ≈6.2 µC cm−2 and saturation polarization (Ps) ≈8.2 µC cm−2 at an applied electric field of 250 MV/m compared to unpoled thin films having Pr ≈4.7 and Ps ≈6.2 µC cm−2. Also, poled P(VDF‐TrFE) thin films show lower coercive field (Ec) ≈94 MV/m compared to an unpoled thin film having Ec ≈105 MV/m. Similarly, poled PVDF‐TrFE‐CFE thin film shows better ferroelectric properties having Pr ≈0.4 and Ps ≈5.7 µC cm−2 at an applied electric field of 200 MV m−1 compared to unpoled thin films having Pr ≈0.4 and Ps ≈4.1 µC cm−2. The storage energy efficiency of unpoled and poled P(VDF‐TrFE‐CFE) thin films is measured to be ≈75% and 80%. Annealing of ferroelectric P(VDF‐TrFE) polymer thin films under an electric field demonstrates improved ferroelectric and electroactive properties. [ABSTRACT FROM AUTHOR]

The active hydroxy-terminated liquid polybutadiene rubber (HTPB) can be prepared into a macromolecular initiator under appropriate conditions. The polymers with specific functions are connected to both ends of HTPB by the method of block copolymerization modification to form block polymers with diverse structures and rich functions. In this paper, the recent research progress of HTPB block polymers in improving the performance of rocket propellants, stimulation-responsive polymers, stretchable semiconductor materials and amphiphilic polymers are reviewed. The future of HTPB block polymers is also prospected. [ABSTRACT FROM AUTHOR]

Polymers with well‐defined structures, synthesized through metal‐catalyzed processes, and having end groups exhibiting different polarity and reactivity than the backbone, are gaining considerable attention in both scientific and industrial communities. These polymers show potential applications as fundamental building blocks and additives in the creation of innovative functional materials. Investigations are directed toward identifying the most optimal and uncomplicated synthetic approach by employing a combination of living coordination polymerization mediated by rare‐earth metal complexes and C–H bond activation reaction by σ‐bond metathesis. This combination directly yields catalysts with diverse functional groups from a single precursor, enabling the production of terminal‐functionalized polymers without the need for sequential reactions, such as termination reactions. The utilization of this innovative methodology allows for precise control over end‐group functionalities, providing a versatile approach to tailor the properties and applications of the resulting polymers. This perspective discusses the principles, challenges, and potential advancements associated with this synthetic strategy, highlighting its significance in advancing the interface of metalorganic chemistry, polymer chemistry, and materials science. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: In recent years, there has been a shift towards using non‐fullerene electron acceptors in organic solar cells (OSCs) as a replacement for fullerene derivatives. This change requires polymer donors that possess compatible physical properties, such as absorption range, HOMO energy level, miscibility, and crystallinity. Moreover, the high cost and poor batch‐to‐batch reproducibility of polymer donors also hinder future large‐scale manufacturing. These emphasize the need to explore alternative types of polymer donors. The imide‐functionalized building units possess several key attributes that make their polymers highly promising for non‐fullerene OSCs. These attributes include ease of synthesis, strong electron‐withdrawing ability, rigid and co‐planar structure, and the ability to easily tune solubility through imide side chains. In this review, we summarized the synthetic routes of imide building units, and the structural evolution of imide‐functionalized polymer donors by focusing on the effects of polymer structure on their physical, optoelectronic, and photovoltaic properties. We hope that this mini‐review will serve as a catalyst for future research on imide‐functionalized polymers toward high‐performance, cost‐effective, and durable organic solar cells (OSCs). [ABSTRACT FROM AUTHOR]

Vibration-fatigue failure occurs when a structure is dynamically excited within its natural frequency range. Unlike metals, which have constant fatigue parameters, polymers can exhibit frequency-dependent fatigue parameters, significantly affecting the vibration resilience of 3D-printed polymer structures. This manuscript presents a study utilizing a novel vibration-fatigue testing methodology to characterize the frequency dependence of polymer material fatigue parameters under constant temperature conditions. In this investigation, 3D-printed PLA samples with frequency-tunable geometry were experimentally tested on an electro-dynamical shaker with a random vibration profile. Using the validated numerical models, the estimation of vibration-fatigue life was obtained and compared to the experimental results. Performing the numerical minimization of estimated and actual fatigue lives, the frequency-dependent fatigue parameters were assessed. In particular, the results indicate that the tested samples exhibit varying fatigue parameters within the loading frequency range of 250–750 Hz. Specifically, as the loading frequency increases, the fatigue exponent increases and fatigue strength decreases. These findings confirm the frequency dependence of fatigue parameters for 3D-printed polymer structures, underscoring the necessity of experimental characterization to reliably estimate the vibration-fatigue life of 3D-printed polymer structures. The utilization of the introduced approach therefore enhances the vibration resilience of the 3D-printed polymer mechanical component. [ABSTRACT FROM AUTHOR]

This study identifies the optimal combination of active and passive thermoplastic materials for producing multi-material programmable 3D structures. These structures can undergo shape changes with varying radii of curvature over time when exposed to hot water. The research focuses on examining the thermal, thermomechanical, and mechanical properties of active (PLA) and passive (PRO-PLA, ABS, and TPU) materials. It also includes the experimental determination of the radius of curvature of the programmed 3D structures. The pairing of active PLA with passive PRO-PLA was found to be the most effective for creating complex programmable 3D structures capable of two-sided transformation. This efficacy is attributed to the adequate apparent shear strength, significant differences in thermomechanical shrinkage between the two materials, identical printing parameters for both materials, and the lowest bending storage modulus of PRO-PLA among the passive materials within the activation temperature range. Multi-material 3D printing has also proven to be a suitable method for producing programmable 3D structures for practical applications such as phone stands, phone cases, door hangers, etc. It facilitates the programming of the active material and ensures the dimensional stability of the passive components of programmable 3D structures during thermal activation. [ABSTRACT FROM AUTHOR]

Polymer composite materials are increasingly used in civil aircraft structures. The failure mode and energy-absorption characteristics of polymer composite structures have garnered significant attention from academia and industry. For thin-walled polymer composite C-channels with layups of [0/90]3s, [45/-45]3s, and [45/90/-45/0]3, low-speed axial compression tests were performed to investigate the failure modes, failure mechanisms, and energy-absorbing characteristics. After parametric studies using [0] and [90] single-element models, stacked shell models of thin-walled composite C-channels were established using the Lavadèze single-layer damage constitutive model, Puck 2000, and Yamada Sun failure criteria. The results show that these thin-walled composite C-channels exhibit a stable progressive crushing process with a local buckling failure mode, encompassing local buckling, fiber break-age, matrix cracks, delamination, and corner cracking. The stacked shell model demonstrates reasonable agreement with the progressive crushing process of thin-walled composites, accurately capturing interlayer matrix failure and interface delamination cracking behavior. A comparison of the specific energy absorption (SEA) and mean crushing force (Fmean) between the simulation and test results yields a difference of less than 6%, indicating a strong correlation between the simulation results and the experimental energy-absorbing characteristics. It also shows that a deep understanding of the parameters is helpful for accurate numerical modeling. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: In recent years, there has been a shift towards using non‐fullerene electron acceptors in organic solar cells (OSCs) as a replacement for fullerene derivatives. This change requires polymer donors that possess compatible physical properties, such as absorption range, HOMO energy level, miscibility, and crystallinity. Moreover, the high cost and poor batch‐to‐batch reproducibility of polymer donors also hinder future large‐scale manufacturing. These emphasize the need to explore alternative types of polymer donors. The imide‐functionalized building units possess several key attributes that make their polymers highly promising for non‐fullerene OSCs. These attributes include ease of synthesis, strong electron‐withdrawing ability, rigid and co‐planar structure, and the ability to easily tune solubility through imide side chains. In this review, we summarized the synthetic routes of imide building units, and the structural evolution of imide‐functionalized polymer donors by focusing on the effects of polymer structure on their physical, optoelectronic, and photovoltaic properties. We hope that this mini‐review will serve as a catalyst for future research on imide‐functionalized polymers toward high‐performance, cost‐effective, and durable organic solar cells (OSCs). [ABSTRACT FROM AUTHOR]

Ultra‐high molecular weight polyethylene (UHMWPE) stands out as the preferred material across a wide spectrum of demanding applications, thanks to its remarkable mechanical, chemical and physical attributes. Nevertheless, processing UHMWPE can be an arduous and time‐consuming endeavor. Traditional melt‐processing techniques, commonly employed for polymers, prove impractical due to the exceedingly high viscosity of the melt that follows from the highly entangled macromolecular chains. Several methods are known to lower the entanglement density of UHMWPE, such as crystallization from a semidilute solution or direct polymerization, resulting in a less interconnected polymer structure. Unfortunately, even with low‐entangled UHMWPE, melt processing remains unviable because of the rapid re‐entanglement of polymer chains upon melting. However, these low‐entangled UHMWPE materials can still be effectively processed in the solid state, a technique employed in the production of high‐performance UHMWPE fibers and tapes, currently the only two feasible geometries. This research reports the development of a solid‐state extrusion method for nascent low‐entangled powder, centering on manipulating the surface energy of the interior wall materials within the extruder and die. Ordinary steel dies proved ineffective for solid‐state extrusion, as they generated excessive friction between the die and UHMWPE, resulting in a rapidly escalating extrusion pressure. However, utilizing dies constructed from temperature‐resistant polymers allowed for extrusion at a consistent pressure without the need for lubricating agents. We demonstrate the practicality of the developed solid‐state extrusion method by fabricating UHMWPE monofilaments and tubes, showcasing its potential in expanding the range of producible UHMWPE geometries. Additionally, a first evaluation of the influence of processing conditions and the entanglement density of the reactor powder used on extrudability, and the properties of the resulting components is presented. Highlights: A process for the solid‐state extrusion of UHMWPE is developed.UHMWPE processing with higher design flexibility than current industrial standards.UHMWPE processing with higher throughput than current industrial standards.Contrary to previous techniques no lubricating agent or co‐extrudate is used. [ABSTRACT FROM AUTHOR]

The molecular structure of the polymer PM6 is elaborately modified through random copolymerization by incorporating simple units of either difluoro‐substituted thiophene (2FT) or dicyano‐substituted thiophene (2CNT). The incorporation of the 2FT unit significantly enhanced the coplanarity of the random copolymers, leading to improved molecular crystallinity, whereas the introduction of the 2CNT unit featured the opposite effect. Thanks to the optimized morphology resembling a fiber‐like interpenetrating network structure, the organic solar cells based on PM6‐10%2FT:IT4F showed higher and more balanced charge mobilities, achieving a power conversion efficiency (PCE) of 12.65%, which is comparable to that of PM6‐based devices. For comparison, the 2CN‐series random copolymers‐based devices exhibited lower PCEs of ˂12%. Interestingly, a superior PCE close to 19.0% is achieved in PM6:L8‐BO:PM6‐20%2CN based ternary device due to the significant improvement in open‐circuit voltage. This work demonstrates that the crystallinity of donor polymers can be enhanced by introducing simple structural units to strengthen the coplanarity of the backbone, thereby achieving an optimized morphology that promotes favorable charge transport. [ABSTRACT FROM AUTHOR]

Biodegradable polymers such as polylactic‐co‐glycolic acids (PLGA) are used for various implantable devices such as tissue scaffolds, drug delivery devices, and biosensors in different forms. However, high‐resolution patterning of biodegradable polymers on implantable devices has not been explored much yet. While electrohydrodynamic printing (EHD) can achieve high‐resolution printing compared to other printing methods, EHD printing of PLGA solutions is rarely attempted due to unstable printing. Such printing instability originates from the volatile nature of PLGA inks, and it causes nozzle clogging or change of ink conditions during printing. Here, PLGA ink formulation and a voltage input profile are studied for stable and high‐resolution EHD printing. Addition of glycerol at an optimal ratio as well as the control of voltage pulse shape strongly influenced both the stability and resolution of EHD printing of PLGA patterns. With the optimized inks and voltage inputs, stable printing of PLGA micropatterns down to 5 µm is achieved on both conductive and insulating surfaces for controlled drug release. Furthermore, use of a ring type electrode allows for EHD printing of PLGA micropatterns on 3D surfaces of PLLA tubes and stent struts. [ABSTRACT FROM AUTHOR]

The performance of triboelectric polymers relies on their molecular structure. Therefore, investigating how to construct high‐performance molecular structures of triboelectric polymers becomes imperative, yet the relationship between microscopic structural parameters and triboelectric performance remains unclear. In this study, the relationship is studied between dihedral angles of adjacent conjugated planes and triboelectric performance. Various polyimide monomers are synthesized to manipulate the conjugated dihedral angles within the molecular chains. Introducing larger dihedral angles in polyimides (PIs) reduces the conjugation between molecular chains, suppressing the formation of charge transfer complexes (CTCs), and widening the energy gap between molecular orbitals. With the increase in dihedral angles, the output performance improved by 100%. The surface charge density of 335 µC·m−2 is achieved through the synergistic effect of the high charge retention capability of the PI film and the high triboelectric properties of the corona‐polarized fluorinated ethylene propylene (FEP). A large dihedral angle can form numerous deep traps and effectively prevent charge escaping while ensuring stable output. This study provides a feasible strategy for investigating the construction of high triboelectric performance molecular structures, enriching the understanding of how molecular structures influence the triboelectric properties of polymer materials and promote high‐performance fluorine‐free and environmentally friendly polymers. [ABSTRACT FROM AUTHOR]

We report the synthesis of a novel class of metal-complexing peptide-based polymers, which we name HyperMAPs (Hyper -loaded M et A l-complexed P olymers). The controlled solid-phase synthesis of HyperMAPs' scaffold peptide provides our polymer with a well-defined molecular structure that allows for an accurate on-design assembly of a wide variety of metals. The peptide-scaffold features a handle for direct conjugation to antibodies or any other biomolecules by means of a thiol-maleimide-click or aldehyde-oxime reaction, a fluorogenic moiety for biomolecule conjugation tracking, and a well-defined number of functional groups for direct incorporation of metal-chelator complexes. Since metal-chelator complexes are prepared in a separate reaction prior to incorporation to the peptide scaffold, polymers can be designed to contain specific ratios of metal isotopes, providing each polymer with a unique CyTOF spectral fingerprint. We demonstrate the complexing of 21 different metals using two different chelators and provide evidence of the application of HyperMAPs on a 13 parameter CyTOF panel and compare its performance to monoisotopic metal-conjugated antibodies. • Current metal chelating polymers for use in mass cytometry design limits amount of metals. • Complexing metals to chelators before attachment to a scaffold provides better quality control. • Our design enables 21 metals and demonstrates similar signal to current polymers. • Spectral deconvolution of multi-isotopic signal is shown, enabling combining isotopes per marker. [ABSTRACT FROM AUTHOR]

Given the environmental concerns surrounding fluoromaterials, the use of high‐cost perfluorinated sulfonic acids (PFSAs) in fuel cells and water electrolysis contradicts the pursuit of clean energy systems. Herein, we present a fluorine‐free dumbbell‐shaped block‐graft copolymer, derived from the cost‐effective triblock copolymer, poly(styrene‐b‐ethylene‐co‐butylene‐b‐styrene) (SEBS), for polymer electrolyte membranes (PEMs). This unique polymer shape led to the alignment of the hydrophobic‐hydrophilic domains along a preferred orientation, resulting in the construction of interconnected proton channels across the membrane. A bicontinuous network allowed efficient proton transport with reduced tortuosity, leading to an exceptional ionic conductivity (249 mS cm−1 at 80 °C and 90 % relative humidity (RH)), despite a low ion exchange capacity (IEC; 1.41). Furthermore, membrane electrode assembly (MEA) prepared with our membrane exhibited stable performance over a period of 150 h at 80 °C and 30 % RH. This study demonstrates a novel polymer structure design and highlights a promising outlook for hydrocarbon PEMs as alternatives to PFSAs. [ABSTRACT FROM AUTHOR]