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The phase behavior of binary blends of AB diblock copolymers of compositions f and 1 − f is examined using field-theoretic simulations. Highly asymmetric compositions (i.e., f ≈ 0) behave like homopolymer blends macrophase separating into coexisting A- and B-rich phases as the segregation is increased, whereas more symmetric diblocks (i.e., f ≈ 0.5) microphase separate into an ordered lamellar phase. In self-consistent field theory, these behaviors are separated by a Lifshitz critical point at f = 0.2113. However, its lower critical dimension is believed to be four, which implies that the Lifshitz point should be destroyed by fluctuations. Consistent with this, it is found to transform into a tricritical point. Furthermore, the highly swollen lamellar phase near the mean-field Lifshitz point disorders into a bicontinuous microemulsion (BμE), consisting of large interpenetrating A- and B-rich microdomains. BμE has been previously reported in ternary blends of AB diblock copolymer with its parent A- and B-type homopolymers, but in that system the homopolymers have a tendency to macrophase separate. Our alternative system for creating BμE is free of this macrophase separation. [ABSTRACT FROM AUTHOR]

We present a comprehensive study using dissipative particle dynamics simulations to investigate phase separation kinetics (PSK) in three-dimensional (3d) polymeric fluids under random photo-illumination. We consider two scenarios: polymer blends with active radicals at one end of each immiscible chain and block copolymer (BCP) melts with photosensitive bonds linking incompatible blocks. The phase separation (PS) is induced by temperature quench of the initial homogeneously mixed system. Simultaneously, the system experiences random photo-illumination, simulated by two concurrent random events: (a) the recombination of active radicals in polymer blends and (b) the breaking of photosensitive bonds in BCP chains. Variations in the bond-breaking probability, Pb, mimic the change in light intensity. The length scale follows power law growth, R(t) ∼ tϕ, where ϕ represents the growth exponent. Increasing Pb results in a gradual transition in growth kinetics from micro-PS to macro-PS, accompanied by corresponding transition probabilities for both systems. Micro-PSK dominates the evolution process at low Pb values. The scaling functions exhibit data overlap for most scaled distances, indicating the statistical self-similarity of evolving patterns. Our study enhances the understanding of PSK in polymeric fluids, revealing the impact of photosensitive bonds and active radicals. Furthermore, it suggests the potential for designing novel polymeric materials with desired properties. [ABSTRACT FROM AUTHOR]

Polymer blends are critical in many commercial products and industrial processes and their phase behavior is therefore of paramount importance. In most circumstances, such blends are formulated with samples of high dispersity, which have generally only been studied at the mean-field level. Here, we extend the renormalized one-loop theory of concentration fluctuations to account for blends of disperse polymers. Analyzing the short and long length-scale fluctuations in a consistent manner, various measures of polymer molecular weight and dispersity arise naturally in the free energy. Thermodynamic analysis in terms of moments of the molecular weight distribution(s) provides exact results for the inverse susceptibility and demonstrates that the theory is not formally renormalizable. However, physically motivated approximations allow for an "effective" renormalization, yielding (1) an effective interaction parameter, χe, which depends directly on the sample dispersities (i.e., Mw/Mn) and leaves the form of the mean-field spinodal unchanged, and (2) an apparent interaction parameter χa that depends on higher-order dispersity indices, for instance Mz/Mw, and characterizes the true limits of blend stability accounting for long-range off-critical fluctuations. We demonstrate the importance of dispersity on several example systems, including both "toy" models that may be realized in computer simulation and more realistic industrially relevant blends. We find that the effects of long-range fluctuations are particularly prominent in blends where the component dispersities are mismatched, especially when there is a small quantity of the high-dispersity species. This can be understood as a consequence of the shift in the critical concentration(s) from the monodisperse value(s). [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 charge transport in conducting polymer blends of poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonate) [PEDOT:PSS] and polyvinyl alcohol (PVA) at 75, 50, 25, and 12 vol. % of PEDOT:PSS is investigated in the temperature range of 300–4.2 K. The scaling fit to percolative transport [σ ∝ |f − fc|t] shows that fc is around 10% and t = 2. The temperature dependent conductivity varies from the critical regime of metal–insulator transition to variable range hopping, along with the alterations in the networks of PEDOT:PSS in PVA. The variation in the exponent (n) in electric field dependent conductivity is more significant as the volume fraction of PEDOT:PSS decreases. The value of n decreases as the thermal contribution to transport dominates, showing the competing roles of both field and temperature. [ABSTRACT FROM AUTHOR]

The subject of this research is a relatively detailed investigation of the rheological, morphological and electrical properties of nanocomposites based on polyolefin elastomer (POE), cyclic olefin copolymer (COC) and multi‐walled carbon nanotubes (MWCNTs). To formulate a mixture of two polymers (COC and POE), the melt mixing method was used and their morphology was studied by SEM technique and it was found that the morphology is of co‐continuous type. When the weight percentage ratio of COC was between 40 and 60, the desired morphology (co‐continuous) appeared. Interfacial tension calculations and TEM images proved that the nanotube particles were stabilized both within the phase of POE as well as at the interface of the two polymer phases. The rheological behavior was analyzed for composite samples containing 0–3 wt % MWCNT. The electrical and rheological percolation thresholds appeared at 1 and a 0.5 percent by weight of nanotube particles, respectively, which may be better to consider as related to the phenomenon of dual percolation. The highest conductivity was obtained for the nanocomposite containing 3% MWCNT. The results of mechanical tests also showed a strong upward trend of properties due to the addition of nanotube. Highlights: The effect of COC content on the morphology of POE/COC blend was investigated.The Morphology for the POE/COC blend at low COC content was droplet‐matrix type.MWCNT has a greater tendency to be in the POE phase than COC.Rheological behavior strongly depended on the amount of nanotube particles.The highest conductivity was obtained for the sample containing 3% MWCNT. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Previous studies have investigated complexation and coacervation of scallop Patinopecten yessoensis male gonad hydrolysates (SMGHs) and polysaccharides influenced by pH and blending ratio. It has been found that SMGHs/polysaccharide composite shows better gel properties under strongly acidic conditions. Thus, the complexation and coacervation of SMGHs and gellan gum (GG) were investigated via turbidimetric titration at different pH values (1–12) and biopolymer blending ratios (9.5:0.5–6:4).Both pHc and pHφ1 exhibited ratio‐independent behavior with constant values at approximately pH 5.8 and pH 3.8, respectively, dividing SMGHs/GG blends into three phases named mixed polymers, soluble complexes and insoluble coacervates, respectively. Overall, SMGHs and GG exhibited synergistic gelation under neutral and acidic conditions, with the initial storage modulus (G') increasing by approximately 42.5‐, 573.7‐ and 3421‐fold and 97.7‐, 550.3‐ and 0.5‐fold, respectively, at pH 7, 5 and 3, compared with SMGHs and GG. As pH decreased from 7 to 3, the initial G' and viscosity η values of SMGHs/GG gels increased by 20.1‐ and 2.3‐fold, respectively, exhibiting the greatest increase in gel strength. Moreover, the free water in the SMGHs/GG system significantly shifted toward lower relaxation times attributed to the immobilization of the outer hydration layers. SMGHs/GG gels in the insoluble phase exhibited denser networks and rougher surfaces, supporting the enhanced rheological properties and water retention capacity of the gel.This work provides a basic foundation for the development of pH‐driven SMGHs/GG gelation by examining complexation and coacervation processes. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In recent years, the hydrogen energy industry has been rapid growth. However, elastomeric sealing materials used in high-pressure hydrogen infrastructure still undergo significant performance degradation due to hydrogen-induced damage. This study focuses on blending thermoplastic polyurethane (TPU), ethylene propylene diene monomer grafted maleic anhydride (EPDM-g-MAH) and ethylene propylene diene monomer (EPDM) to enhance blends' performance and achieve complementarity. Adding EPDM-g-MAH as a compatibilizer improves interfacial compatibility in the blends, promoting a more uniform dispersion of EPDM as the dispersed phase within TPU. The hydrogen bonds between TPU and EPDM chains significantly reduce the free volume in the blends, thereby complicating and torturing the hydrogen diffusion paths within the blends. Results show that the hydrogen permeability of the blends (TPU/EPDM-g-MAH/EPDM ratio 90/2/10) is 1.294 × 10−9 mol·m/(m2·s·MPa), which is 37 % lower than TPU and 87 % lower than EPDM. The blends also exhibit excellent hydrogen barrier properties compared to reported typical rubber sealing materials. Furthermore, after exposure to high-pressure hydrogen, the sample (TPU/EPDM-g-MAH/EPDM ratio 90/2/10) shows minimal hydrogen-induced damage to its internal structure, with changes in mechanical properties (tensile strength, elongation at break, and hardness) remaining within 6 %. A novel approach to developing high-performance elastomeric sealing materials with excellent hydrogen barrier properties and resistance to hydrogen-induced damage is presented in this work. • Innovative approach for elastomer sealing materials in hydrogen infrastructure. • EPDM-g-MAH enhances interfacial compatibility, thereby improving blend uniformity. • TPU/EPDM blends containing EPDM-g-MAH exhibit enhanced hydrogen barrier properties. • Minimal hydrogen-induced damage was observed in TPU/EPDM-g-MAH/EPDM blends. [ABSTRACT FROM AUTHOR]

With exceptional photochromic and photoluminescent properties, spiropyrans have demonstrated significant potential for advanced information encryption and anti‐counterfeiting applications. However, its inherent water insolubility leads to incompatibility with aqueous polymers, and even more, its ease of leaching from the matrix hinders the formation of stable stimuli‐responsive platforms through direct blending with all polymers. Here, the fabrication of amphiphilic spiropyran‐octapeptide molecules is reported that can spontaneously self‐assemble into highly water‐dispersible supramolecular nanofibers in water. These assemblies exhibit universal polymer matrix compatibility while retaining the rapid photo‐responsiveness of spiropyrans. The formation of strong interactions between the supramolecular assembly and polymer chains ensures the long‐term stability of the resultant stimuli‐responsive materials in aqueous environments. These platforms fully preserve the base polymers’ processing properties, with silk fibroin as the matrix offering exceptional opportunities for constructing photo‐responsive platforms in various forms (e.g., films, gels, fibers, and coatings) with multiple functionalities using diverse solution processing techniques. Integrating distinct photochromic and photoluminescent responses within a single format without interference, combined with environmental stability and processing flexibility, enables the creation of dual‐mode, high‐security encryption devices for diverse application scenarios. The outlined strategy provides innovative concepts for developing high‐performance, versatile intelligent systems utilizing stimulus‐responsive molecules. [ABSTRACT FROM AUTHOR]

[Display omitted] Intelligent shape memory polymer can be potentially used in manufacturing implantable devices that enables a benign variation of implant dimensions with the external stimuli, thus effectively lowering insertion forces and evading associated risks. However, in surgical implantation, biomaterials-associated infection has imposed a huge burden to healthcare system that urgently requires an efficacious replacement of antibiotic usages. Preventing the initial attachment and harvesting a biocidal function upon native surfaces may be deemed as a preferable strategy to tackle the issues of bacterial infection. Herein, a functionalized polylactic acid (PLA) composite membrane assembled with graphene (GE, a widely used photothermal agent) was fabricated through a blending process and then polydimethylsiloxane utilized as binders to pack hydrophobic SiO 2 tightly onto polymer surface (denoted as PLA-GE/SiO 2). Such an active platform exhibited a moderate shape-memory performance upon near-infrared (NIR) light stimulation, which was feasible for programmed deformation and shape recovery. Particularly stirring was that PLA-GE/SiO 2 exerted a pronounced bacteria-killing effect under NIR illumination, 99.9 % of E. coli and 99.8 % of S. aureus were effectively eradicated in a lean period of 5 min. Furthermore, the obtained composite membrane manifested excellent antiadhesive properties, resulting in a bacteria-repelling efficacy of up to 99 % for both E. coli and S. aureus species. These findings demonstrated the potential value of PLA-GE/SiO 2 as a shape-restorable platform in "kill&repel" integration strategy, further expanding its applications for clinical anti-infective treatment. [ABSTRACT FROM AUTHOR]

Great challenges exist in producing reliable welding between metals and polymer composites. In this study, self‐riveting welding (SRW) is employed to obtain metal–polymer hybrid joints with high load‐bearing capability. In this investigation, it is shown that the SRW joints with a prefabricated hole of 5.8 mm in diameter are characterized by fewer void defects with sufficient polymer filling, a tightly bonded joint interface, and a relatively uniform stress distribution along the joint interface during the tensile test, leading to the high load‐bearing capability of the SRW joints. The maximum average tensile force is 1.5 kN. The fracture occurs across the polymer composite rather than along the joint interface. In the results, it is shown that SRW has the potential to be developed into a method for fabricating reliable hybrid joints for the aerospace and automotive industries. [ABSTRACT FROM AUTHOR]

This paper takes the catalytic cracking unit of a petrochemical industry as an example to explore the effects of blending hydrogenated tail oil on the distribution and quality of catalytic cracking products, and analyzes the reasons. The results showed that blending hydrogenated tail oil can significantly reduce the output of dry gas and oil slurry. Every increase of 1 ton of hydrogenated tail oil refining, the output of oil slurry decreases by 0.14 tons, dry gas decreases by 56 m³, and gasoline output increases by 0.26 tons. The blending of hydrogenated tail oil will reduce the aromatic hydrocarbon content in gasoline components, decrease the density of gasoline components, and lower the distillation temperature. As the blending amount of hydrogenated tail oil increases, the C3 content in the liquefied petroleum gas decreases and the C4 content increases . This is attributed to the fact that the blending of hydrogenated tail oil inhibits the deep reaction of catalytic cracking, reduces the generation of C3 and below components and deep cracking products such as slurry, and increases the yield of liquids above C4. As the blending amount of hydrogenated tail oil increases, C3 and C4 components become the boundary line for the impact of hydrogenated tail oil blending on the depth of catalytic cracking reaction. [ABSTRACT FROM AUTHOR]

Poly ether ether ketone (PEEK) is a premier engineering plastic, which has gained considerable attention in recent years. Our prior research investigated crystallization template techniques and pore formation mechanisms within the PEEK/poly (ether imide) system, paving the way for the development of hierarchically porous membranes (HPMs). Compared to single‐porous membranes, HPMs demonstrate enhanced flux and high mass transfer efficiency simultaneously, effectively mitigating the trade‐off effects. In this study, we focused on fabricating PEEK HPMs through precise manipulation of a polymer ternary blend system. The meticulous tuning enables intricate control of the hierarchical pore morphology of PEEK at two distinct scales. The finite element simulations not only underscored the crucial role of hierarchical pores in bolstering separation efficiency, but also exhibited strong concordance with the experimental findings. This study provides guidance for future optimization of HPMs with superior separation performance. [ABSTRACT FROM AUTHOR]

The environmental effects of airborne micro‐ and nano‐size plastic particles are poorly understood. Microscopy and chemical analyses of atmospherically deposited particles on snow surfaces at high elevation (2,865–3,690 m) in the Upper Colorado River basin (UCRB; Colorado Rocky Mountains) revealed the presence of black substances intimately associated with microplastic fibers, particles interpreted to have originated as tire matter. Identical and similar particles occur in shredded tires and road‐surface samples. The substance responsible for the black color of all tires is carbon black, a graphitic light‐absorbing tire additive produced by hydrocarbon combustion that homogeneously permeates the mixture of tire polymers and other additives. Such black tire matter may thus exert radiative effects closely similar to those of black carbon. The presence in snow of many organic compound types common to tires, measured by two‐dimensional gas chromatography, suggests that atmospherically deposited black road‐tire‐wear matter is among the light‐absorbing particulates that advance the onset and rate of snow melt in the UCRB. The mass of road‐tire‐wear particles shed from vehicles may be estimated by multiplying measured amounts of eroded tire‐per‐distance traveled by vehicular distances. Under a combination of measurements and assumptions about the amounts and radiative properties of atmospheric tire‐wear particles, the radiative effects of these particles might add about 10%–30% to those effects from black carbon, an estimate ripe for revision. On regional and global scales, the amounts and effects of emitted and deposited tire‐wear matter likely vary by factors of geographic source, transport pathway, and depositional setting. Plain Language Summary: A major source for airborne microplastic particles is road‐tire wear. Microscopy and chemical analyses of wind‐blown particles on dirty, high‐elevation (2,865–3,690 m) snow surfaces in the Colorado Rocky Mountains revealed the presence of black substances intimately mixed with microplastics, particles interpreted as tire matter. Identical and similar particles occur in shredded tires and in samples collected from road surfaces. The black substance responsible for the black color of all tire particles is carbon black that homogeneously permeates the mixture of tire polymers and other additives. The mass of particles produced by road‐tire wear may be estimated by multiplying measured amounts of eroded tire‐per‐distance traveled by vehicular travel distances. Under assumptions of amounts of tire‐wear matter emitted to the atmosphere, their presence as light‐absorbing particles likely contribute to melting of snow and ice as well as to warming the atmosphere. Key Points: Light absorbing particles, as blackened microplastic matter from road‐tire wear, occur in snow of the Colorado Rocky Mountains (2013–2021)The mass of road‐tire‐wear particles annually generated is estimated to be 6,550 kt, of which about 655–1,965 kt might become airborneThe results are relevant to radiation modeling of snow and ice surfaces as well as the atmosphere [ABSTRACT FROM AUTHOR]

The subject of the research conducted by differential scanning calorimetry (DSC) was hydrated mixtures of polyethylene glycol and gentamicin (GEN) in a 1:1 (w/w) ratio. In this way, a system with a particularly high ability to form hydrogen bonds was created. It was postulated that studying the effective activation energy (EA) of the thawing process of diverse hydrated polymer mixtures will indirectly allow for an attempt to assess the distribution of water molecules in the examined material in future studies. This article presents a detailed analysis of the impact of selected parameters on the calculation of EA using the Belichmaer and Duswalt methods. The research focused on assessing how the interpolation method affects the accuracy of results obtained from these techniques. The interpolation method was analyzed in terms of its ability to accurately replicate experimental data. By evaluating the impact of the number of points from the DSC curve used in linear interpolation, a standard deviation from the average value of EA was obtained, respectively: 2.4% for the Belichmaer method and 1.9% for the Duswalt method. The article also shows that by using both methods simultaneously, it is possible to detect the moment when additional endothermic and exothermic reaction activity becomes present in the reaction curve. This allowed for the avoidance of the depletion error. Computer modeling and simulations were used to compare the effectiveness of both techniques in various scenarios. The results showed that the choice of interpolation method and taking into account the depletion error significantly affect the accuracy of calculating EA. The computed activation energy via Duswalt method was EA = 363.32 kJ mol−1 with a standard deviation of 7.07 kJ mol−1 and using the Belichmaer method the EA was 364.81 kJ mol−1, with a standard deviation of 9.10 kJ mol−1. [ABSTRACT FROM AUTHOR]

Inorganic fillers like hexagonal boron nitride (h‐BN) have the potential to enhance the thermal conductivity of polymer mixtures. However, it has been restricted due to poor dispersion of particles in polymer matrices by melt mixing process. The addition of inorganic powders into sticky prepolymer is expected to alleviate the aggregation of powders. In this paper, h‐BN/polymethyl methacrylate (PMMA) composites were prepared by in situ polymerization of methyl methacrylate (MMA) with 5 and 20 μm of h‐BN particle as fillers respectively, for even distribution of fillers with in composites. The structures and properties of composites were characterized by FT‐IR, DSC, TGA, SEM, laser thermal conductivity meter and universal electronic tester. By SEM, it can be seen that a highly uniform dispersion of h‐BN in PMMA. When the mass fraction of h‐BN is 20 wt%, the thermal conductivity of the composites is increased by 107% for 5 μm h‐BN and 189% for 20 μm h‐BN, respectively. With the mass constituting of 5 wt% h‐BN, majority of mechanical characteristics of the composite, such as tensile strength, tensile modulus, along with impact strength, are enhanced, alongside a decrease in bending strength. This work would provide a filling strategy of h‐BN into the polymer matrices to achieve uniform dispersion, and enhance both the thermoconductivity and mechanical strength of thermoplastic composites. Highlights: A technique for creating h‐BN/PMMA composites using in suit redox polymerization.Ehancing the thermal conductivity of these composites is achievable through the even distribution of h‐BN flakes within the PMMA matrix.It provides a reference for the design of future h‐BN/PMMA composites with favorable the thermal conductivity which achieves a good balance between performance and cost. [ABSTRACT FROM AUTHOR]

While blending with flexible polymers has been a commonly employed strategy to enhance the toughness of polylactic acid (PLA), it's still a great challenge to avoid the sacrifice of tensile strength at the same time. In this work, we demonstrate a promising route to simultaneously improve the strength and toughness of PLA by compounding PLA with poly(ε‐caprolactone) (PCL) and PLA grafted multi‐walled carbon nanotubes core‐shell nanofiller (MWNT‐PCLPLA) via a two‐step ring‐opening polymerization and have analyzed the strengthening and toughening mechanism through molecular dynamics simulation. The double polymer layers of MWNT‐PCLPLA effectively improve the interfacial interaction between MWNTs and the matrix, in which the outer PLA layer has the same molecular structure with the matrix and facilitates stress transfer, while the flexible PCL layer can absorb energy through self‐deformation and induce local plastic deformation of the matrix. When the content of MWNTs was only 1 wt%, the strength and elongation at break of PLA/MWNT‐PCLPLA nanocomposites were increased by 47.92% and 690.11% compared to neat PLA. Furthermore, the toughness of nanocomposites reached 11.93 MJ/m3, which is about 16 times that of neat PLA. This novel core‐shell nanofiller with double polymer layers is expected to be further applied in other polymer systems. Highlights: A core‐shell nanofiller with double polymer layers was synthesized.Improved dispersion and interfacial compatibility of nanofillers in matrix.The crystallization ability of PLA was improved by functionalized MWNTs.Simultaneously improved strength and toughness of PLA/MWNT‐PCLPLA nanocomposite. [ABSTRACT FROM AUTHOR]

The dimerization of small molecule acceptors (SMAs) is a promising strategy for enhancing the long‐term stability and power conversion efficiency (PCE) of organic solar cells (OSCs). However, the reported DSMAs are primarily limited to end‐linked molecular configurations, highlighting the need for further exploration of various dimer architectures. Herein, the development of two distinct core‐linked dimerized SMAs (DYF‐V and DYF‐E) are reported with tailored linker structures (vinylene and ethynyl, respectively), achieving high‐performance OSCs (PCE = 18.53%). Interestingly, a subtle change in the linker structures results in markedly different molecular properties and photovoltaic performances of the dimer acceptors. DYF‐E with an ethynyl linker exhibits more twisted backbone conformation and mitigated aggregation property compared to DYF‐V, inducing desirable blend morphologies with a polymer donor including high crystallinity, face‐on oriented packing structures, and well‐intermixed domains. Thus, the DYF‐E‐based OSCs exhibit a high PCE (17.02%), which significantly outperforms the DYF‐V‐based OSCs (PCE = 9.98%). Furthermore, the ternary OSCs based on DYF‐E achieve a higher PCE of 18.53%. Thus, this study highlights the significance of selecting an appropriate linker in core‐linked dimerized SMAs for producing high‐performance OSCs. [ABSTRACT FROM AUTHOR]

Polymer dielectrics play an irreplaceable role in electrostatic capacitors in modern electrical systems, and have been intensively studied with their polarization and breakdown strength (Eb) optimized for high discharged energy density (Ud) at elevated temperatures. Small molecules have been explored as fillers, yet they deteriorate thermal stability of matrix which limits their optimal loading to ~1 wt%. Herein, we develop a polymer blend dielectric consisting of common polyimide and a bifunctional dipolar glass polymer which are synthesized from two small molecule components with wide band-gap and large dipole moment. The bifunctional dipolar glass with large molecular weight not only maintains thermal stability of polymer blends even at a high loading of 10 wt%, but also induces substantial enhancement in polarization and Eb than any of individual components does, achieving an ultrahigh Ud of 8.34 J cm−3 (150 °C) and 6.21 J cm−3 (200 °C) with a charge-discharge efficiency of 90%. The authors develop a polymer blend dielectric consisting of common polyimide and a bifunctional dipolar glass polymer which are synthesized through condensation polymerization of two small molecule components with wide band-gap and large dipole moment. [ABSTRACT FROM AUTHOR]

Self-consistent field (SCF) analysis is an indispensable tool for predicting the microphase separation structures of polymer alloys. However, the computation of the phase-separated structures in the equilibrium state is computationally intensive, leading to high costs. To address this challenge, we propose a novel deep learning approach that leverages a generative adversarial network (GAN), a powerful deep generative model, to accelerate SCF analysis. Specifically, we trained the GAN using comprehensive data obtained from SCF analysis, enabling us to generate various images of feasible structures that are similar to the SCF analysis results. Our results demonstrate that the latent variables in the GAN are linked to the physical parameters and features of the phase-separation structures. [ABSTRACT FROM AUTHOR]

Chitin and chitosan are versatile and valuable biomaterials, with chitosan being abundantly found in the exoskeletons of crustaceans, insects, arthropods, and mollusks. The chemical extraction of chitin involves a series of steps, including deproteinization, demineralization, and decolorization. Chitosan is often combined with various polymeric materials, and polymer blending can enhance the mechanical properties of the resulting bioproduct. In this study, composites of poly(lactic acid) (PLA) with chitosan (Ch) and cellulose acetate (CA) were successfully fabricated using extrusion and injection molding techniques. The chitosan content, ranging from 0 to 7.5 wt. %, was incorporated into the PLA matrix to assess the impact of filler content on the mechanical and morphological properties of the composites. The chitosan powder was first alkalized and then etherified to obtain modified chitosan, specifically o-carboxymethylated chitosan (O-CMCh). The addition of chitosan led to a reduction in tensile strength, flexural strength, modulus of elasticity, and impact strength. However, the hardness of the composite improved with the inclusion of chitosan. The mesoporous structure of chitosan was characterized using nitrogen adsorption and desorption measurements. Morphological analysis revealed that the composite containing 3.75 wt. % chitosan exhibited significantly less fracture surface compared to other composites. HIGHLIGHTS: Chitosan is obtained from chitin through deacetylation and chemical modification (O-CMCh) is achieved through alkalization followed by etherification. PLA/CMCh-CA composites fabricated through extrusion and injection molding. The tensile strength gradually decreased from 55.09 to 1.3 MPa. The Flexural strength drastically declined from 93.37 to 19.10 MPa. The impact strength decreased with addition of Ch whereas, hardness increased. [ABSTRACT FROM AUTHOR]

In this work, we detail an ultrafast pump-probe transient absorption (TA) spectrometer capable of probing the near-infrared (NIR) spectral region from 900 to 2350 nm simultaneously. Two key advances were required to overcome previous spectral window limitations, which typically result from constrained supercontinuum ranges (e.g., 1700 nm) and/or InGaAs detector line rates, especially those with >1700 nm range. First, we generated a broadband NIR supercontinuum using the 1980 nm idler beam of an optical parametric amplifier and implement a unique spectral filtering scheme to balance the detected spectrum. Second, we used a prism-based spectrometer system equipped with high speed InGaAs cameras having ∼2500 nm sensitivity cutoffs. To the best knowledge of the authors, such an extended probe range was previously inaccessible because the combination of two optical geometries either using different supercontinuum crystal materials for generating the NIR and shortwave infrared (SWIR) regions, or using differing pump wavelengths, were required. Finally, we demonstrate the performance and capabilities of the ultrabroadband TA spectroscopy system by presenting data showing ultrafast charge photogeneration in a polymer : fullerene blend thin-film and comparing the results to the literature with a complete agreement. [ABSTRACT FROM AUTHOR]

This paper presents the development of the blend polymer solid electrolyte films (BPSE) for potential applications in electrochemical devices. Two host polymers, polyvinyl alcohol (PVA) and polymethyl methacrylate (PMMA), along with the salt KI, are employed to create the solid polymer electrolytes (SPEs). The synthesis involves varying the weight percentage of salt within the SPEs to investigate its impact on the material properties. Conductivity measurements are conducted using AC impedance spectroscopy, unveiling the conductivity behavior of the BPSEs. Additionally, surface morphology is characterized using polarized optical microscopy (POM) at 10 pixel resolution, offering a detailed examination of the film's microstructure. This comprehensive study not only contributes to the understanding of the fundamental properties of BPSEs but also opens avenues for their utilization in various electrochemical applications. [ABSTRACT FROM AUTHOR]

Environment-friendly polymer blends of poly(lactic acid) (PLA) and itaconic acid (IA), poly(itaconic acid) (PIA), poly(itaconic acid)-co-poly(methyl itaconate) (Cop-IA), and net-poly(itaconic acid)-ν-triethylene glycol dimethacrylate (Net-IA) were performed via melt blending. The compositions studied were 0.1, 1, 3, and 10 wt% of the diverse chemical architectures. The research aims to study and understand the effect of IA and its different architectures on the mechanical, rheological, and thermal properties of PLA. The PLA/IA, PLA/PIA, PLA/Cop-IA, and PLA/Net-IA blends were characterized by dynamic mechanical thermal analysis, rotational rheometer (RR), thermogravimetric analysis, differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy. The complex viscosity, storage module, and loss module for the RR properties were observed in the following order: PLA/Cop-IA, PLA/Net-IA, and PLA/PIA > PLA > PLA/IA. Thermal stability improved with increasing concentrations of Cop-IA and Net-IA. In the same way, the mechanical properties were enhanced. In addition, the micrographs illustrated the formation of fibrillar structures for all blends. The crystallinity degree displayed higher values for the blends that contain Net-IA > Cop-IA than IA > PIA. Therefore, IA and its architectures can influence these studied properties, which have potential applications in disposable food packing. [ABSTRACT FROM AUTHOR]

A covalent adaptable network (CAN) of semicrystalline polyolefin blends with triple-shape memory effects was fabricated by the reactive melt blending of maleated polypropylene (mPP) and maleated polyolefin elastomer (mPOE) (50 wt/50 wt) in the presence of a small amount of a tetrafunctional thiol (PETMP) and 1,5,7-triazabicyclo [4,4,0]dec-5-ene (TBD). The polymer blend formed a chemically crosslinked network via the reaction between the thiol group of PETMP and maleic anhydride of both polymers in the blend, which was confirmed by FTIR, the variation of torque during the melt mixing process, a solubility test, and DMA. DSC analysis revealed that the crosslinked polyolefin blends show two distinct crystalline melting transitions corresponding to each component polymer. Improved tensile strength as well as elongation at break were observed in the crosslinked blend as compared to the simple blend, and the mechanical properties were maintained after repeated melt processing. These results suggest that thermoplastic polyolefin blends can be transformed into a high-performance and value-added material with good recyclability and reprocessability. [ABSTRACT FROM AUTHOR]

This study explores the impact of butadiene rubber (BR) crystallization on the low-temperature properties of butadiene/silicone (VMQ) rubber blends (BR/VMQ) designed for Martian applications. Two types of BR, semi-crystalline high-cis Buna CB24 and amorphous Buna CB550, were blended with VMQ, and their mechanical and thermal properties were evaluated. Kinetics of vulcanization, static mechanical properties, dynamical mechanical analysis, thermal shrinkage, and differential scanning calorimetry were utilized. The research demonstrates that the semi-crystalline BR improves mechanical properties but induces greater shrinkage at low temperatures. Conversely, using amorphous BR provided more consistent mechanical properties across the Martian temperature range and reduced material shrink by 6.71% for samples with carbon black, by 8.36% for samples with silica, and by 11.63% for unfilled samples. Future research will be required to evaluate the impact of volume change on the sealing properties of the BR/VMQ blends. [ABSTRACT FROM AUTHOR]

Actuator systems are among the most noteworthy aspects of the rapidly expanding field of smart and multifunctional materials, which is having a substantial impact on a number of application areas. Ionic liquids (ILs) are a particularly relevant option for the development of hybrid materials for actuator applications, because of their simple processing and tailored response. This review work focuses on ionic liquid‐based polymer blends for soft actuator applications. The main properties of IL for these applications are highlighted and the state of the art of actuator devices is presented by the type of polymer matrix. Finally, the main conclusions and future trends are presented, in order to properly tailor the characteristics and functional response of IL‐blends for actuator applications. [ABSTRACT FROM AUTHOR]

Electrode materials for application in lithium‐ion batteries are commonly probed by X‐ray diffraction (XRD) to investigate their crystalline structure. Grazing incidence wide‐angle X‐ray scattering (GIWAXS) is an extension to XRD since in‐plane structures are also accessible. Additionally, with grazing incidence small‐angle X‐ray scattering (GISAXS), morphological information on the nanoscale can be revealed. In this work, the nanostructure of battery electrodes, which consist of lithium iron phosphate (LiFePO4) as active material, carbon black (CB) as conducting agent, and the polymeric binders polyvinylidenefluoride (PVDF) and poly((trifluoromethane) sulfonimide lithium styrene) (PSTFSILi) is studied by performing GISAXS and GIWAXS. The chemical nature of the binder is tuned by blending PVDF and PSTFSILi. Specifically, a series of LiFePO4 electrodes with polymer blends of the common, non‐conducting PVDF and the single‐ion conducting PSTFSILi with different weight ratios as binders is investigated to understand the influence of the binder on the structure of the electrode in detail. Scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS) complement these studies to correlate the morphology and structure with the electrochemical behavior. It is found that LiFePO4 crystallites do not exhibit any preferred orientation with respect to the substrate, irrespective of the binder composition, but their size depends on the binder composition. [ABSTRACT FROM AUTHOR]

The main purpose of this study was to investigate the relationship between microstructure and mechanical performance of polylactic acid when mixed with styrene-ethylene butylene-styrene copolymer and also graphene nanoplatelets. For this purpose, a series of neat polymer blends were first prepared with varying mixing ratios through a one-step melt mixing technique. Subsequently, the effect of various loadings of graphene nanoplatelets on the best mixing ratio (optimal composition) of the binary blend was investigated. To understand the different performances of various nanocomposites, the correlation of mechanical, rheological, and microstructural properties was thoroughly investigated using X-ray diffraction, scanning electron microscopy, linear viscoelastic behavior, tensile testing, and impact strength analyses. Furthermore, the influence of the mixing sequence of nanocomposites preparation on the microstructure and mechanical performance of nanocomposites was studied. Results demonstrated that the incorporation of graphene nanoplatelets as well as mixing sequence has a substantial effect on the final properties of prepared nanocomposites which was deeply discussed. [ABSTRACT FROM AUTHOR]

Polybenzoxazines (PBz) are advanced thermosetting phenolic resins with many advantages, including producing nontoxic by-products, molecular design flexibility, minimum shrinkage, and low water absorption. Nevertheless, some issues might occur when synthesizing PBz, such as their brittleness, which necessitates the incorporation of some additives, such as adding another polymer or some nanocomposite material to enhance the performance of PBz. Polymer nanocomposites have emerged as multifaceted and advanced materials in recent years to overcome the disadvantages of PBz. The development of polymer nanocomposites has broadened the scope of possible uses for coatings and adhesives. Researchers constantly discover new methods for creating polymer nanocomposite coatings. The modification of fillers and the manufacturing processes used determine the properties of polymer nanocomposite coatings. Depending on various features and application types, polymer nanocomposite coatings can be classified into conductive, biocompatible, and intelligent nanocomposite coatings. Nanocomposite adhesives can be classified based on their specific performance features, such as structural, biomimetic, pressure-sensitive, and conductive. The use of newly produced polymer nanocomposites has become increasingly common in several areas of modern technology, including applications such as corrosion protection and accelerated regeneration of biological tissue. The use of polymer nanocomposites has resulted in a substantial revolution in coatings and adhesives. This review aims to shed light and provide information on using polybenzoxazine nanocomposites and their most recent coating implementation. [ABSTRACT FROM AUTHOR]

Scaffold‐based tissue engineering provides an efficient approach for repairing uterine tissue defects and restoring fertility. In the current study, a novel trilayer tissue engineering scaffold with high similarity to the uterine tissue in structure was designed and fabricated via 4D printing, electrospinning and 3D bioprinting for uterine regeneration. Highly stretchable poly(l‐lactide‐co‐trimethylene carbonate) (PLLA‐co‐TMC, "PTMC" in short)/thermoplastic polyurethane (TPU) polymer blend scaffolds were firstly made via 4D printing. To improve the biocompatibility, porous poly(lactic acid‐co‐glycolic acid) (PLGA)/gelatin methacryloyl (GelMA) fibers incorporated with polydopamine (PDA) particles were produced on PTMC/TPU scaffolds via electrospinning. Importantly, estradiol (E2) was encapsulated in PDA particles. The bilayer scaffolds thus produced could provide controlled and sustained release of E2. Subsequently, bone marrow derived mesenchymal stem cells (BMSCs) were mixed with gelatin methacryloyl (GelMA)‐based inks and the formulated bioinks were used to fabricate a cell‐laden hydrogel layer on the bilayer scaffolds via 3D bioprinting, forming ultimately biomimicking trilayer scaffolds for uterine tissue regeneration. The trilayer tissue engineering scaffolds thus formed exhibited a shape morphing ability by transforming from the planar shape to tubular structures when immersed in the culture medium at 37°C. The trilayer tissue engineering scaffolds under development would provide new insights for uterine tissue regeneration. [ABSTRACT FROM AUTHOR]

Ethylene‐octene copolymer (EOC, three EOCs with different octene content used in this study) and propene‐ethylene copolymer (EPC, three EPCs with different ethylene content used in this study) can have effects on the crystallization dynamics, crystal structure, and foaming properties of ethylene‐vinyl acetate copolymer (EVA). For unfoamed EVA/EOC and unfoamed EVA/EPC blends, both EVA/EOC and EVA/EPC blends show phase separation structure. The foam cells in EVA/EOC blends have better uniformity compared to those in EVA/EPC blends, which result from the better compatibility of EVA and EOC than EVA and EPC obtained from the morphology analysis. For the blends with different crystallization ability of EOC or EPC, the blends with lower crystallinity has more uniform cell distribution than blends with higher crystallinity, due to the crystallization zone cause heterogeneous crosslinking and foaming of the blend. Both EOC and EPC can impart higher elasticity to EVA foamed materials. EOC was found to be more suitable for blending with EVA for foamed materials, offering the potential to obtain EVA/EOC foamed materials with excellent performance. Highlights: Ethylene‐octene copolymer with higher octene content has better effect on foaming property of ethylene‐vinyl acetate copolymer than ethylene‐propylene copolymer.Ethylene‐propylene copolymer can decrease the foaming temperature of ethylene‐vinyl acetate copolymer.A mechanism of foaming for ethylene‐vinyl acetate copolymer/semi‐crystallized polymer blends is proposed.Achieved in‐depth understanding of structure–property relationship about ethylene‐vinyl Acetate copolymer/polyolefin elastomer foamed material. [ABSTRACT FROM AUTHOR]

Lithium-ion based Solid Polymer Electrolytes are synthesized by incorporating lithium perchlorate (LiClO4) salt with Iota-Carrageenan (IC) / Acacia Gum (AG) plasticized with ethylene glycol (EG) by solution casting method. The X-ray diffraction and Fourier transform infrared analysis are used to analyze the structural and molecular complexation. From the AC impedance analysis spectra, it is found that the incorporation of 15 wt% of LiClO4 salt into a blend polymer electrolyte (IAO15) shows the maximum ionic conductivity of 2.02 × 10−2 S/cm and minimum activation energy (0.022 eV). The conduction mechanism for IAO15 sample follows two models (CBH and QMT). The dielectric and modulus spectra confirm the non-Debye nature of the sample. From the Transference Number Measurement, it is observed that the conductivity is due to Li ions and IAO15 sample is chosen for the fabrication of a Symmetrical supercapacitor. At 3.6 Ag−1 current density, the power and energy densities are noted as 7452 Wkg−1 and 165.6 Whkg−1 respectively. [ABSTRACT FROM AUTHOR]

Blending polylactide (PLA) with poly(propylene carbonate) offers potential solution to mitigate the greenhouse effect due to PLA's lower carbon dioxide (CO2) emissions and its use of CO2 as a monomer in PPC synthesis. In this investigation, a series of PLA and PPC blends were prepared using the solvent casting method to address their respective weaknesses. The blends exhibited partial compatibility, as evidenced by a noticeable shift in the glass transition temperatures toward each other. Tensile testing revealed that the incorporation of PPC improved the elongation properties of PLA. The degradation characteristics of the blend films were evaluated based on changes in the monolayer's occupied area, the properties of the bulk film, and changes in surface morphology. Results indicated that PPC content accelerated hydrolytic degradation but slowed enzymatic degradation in the blends. Hydrolytic and enzymatic degradation significantly impacted the mechanical properties of PLA/PPC blends, prolonging the degradation process through chain scission. [ABSTRACT FROM AUTHOR]

This study investigates the optical, structural, and dielectric properties of NiO nanoparticles (NPs) incorporated into a poly(vinyl alcohol)/sodium alginate (PVA/SA) polymer blend. The x-ray diffraction (XRD) pattern confirmed the formation of face-centered cubic NiO NPs with a crystallite size of around 9.9 nm and lattice strain of 5.6 × 10−3, as determined by the Williamson–Hall method. High-resolution transmission electron microscopy (HRTEM) revealed spherical NiO NPs with sizes ranging from 5 nm to 12 nm. The embedding of NiO NPs into the matrix structure of PVA/SA was confirmed by peak shifting and new peaks from the XRD patterns, and the appearance of spherical nanoparticles with size ranging between 5 nm and 12 nm from HRTEM images. Significant shifting was observed in the Fourier transform infrared (FTIR) spectral bands, indicating strong interaction between the blend components and NiO. Optical studies showed that doping of PVA/SA with NiO NPs enhanced the material's absorption, with a consequent effect on the optical energy band gap, demonstrated by a red shift in the absorption edge with a decrease from 5.0 eV for pristine PVA/SA to 0.09 eV for the 8 wt.% NiO-doped film. In addition, dielectric studies showed an increase in conductivity with the addition of NiO NPs, suggesting their suitability for solid polymer electrolyte applications. [ABSTRACT FROM AUTHOR]

Disordered polymer chain entanglements within all‐polymer blends limit the formation of optimal donor–acceptor phase separation, and thus the performance of all‐polymer organic solar cells (all‐PSCs). Considering the challenge and importance of morphology regulation in all‐PSCs, a diluted layer‐by‐layer (N‐LBL) strategy is thereby adopted to fine‐tuning the properties of all‐polymer blends. When comparing the traditional PM6:PY‐IT based bulk‐heterojunction (BHJ) film and PM6/PY‐IT layer‐by‐layer (LBL) film, the N‐LBL film, which is prepared from diluted PM6 (with 3% PY‐IT) bottom layer and diluted PY‐IT (with 6% PM6) top layer, displayed a clearer bi‐continuous fibrillar network and a higher exciton generation process. Benefiting from these unique characters, the all‐PSC consisting the N‐LBL active layer exhibited a short‐circuit current density over 26 mA cm−2 and a power conversion efficiency (PCE) of 18.33%, which are both higher than those of BHJ (16.88%) and LBL (17.13%) devices. Moreover, the universality of the dilution strategy in other all‐polymer blends (PM6 and PY‐DT, PM6 and PY‐FT‐o) is also demonstrated with unanimously improved device performance. This work underscores the effectiveness of the diluted layer‐by‐layer method in tuning the morphologies and charge dynamics for high‐performance all‐PSCs. [ABSTRACT FROM AUTHOR]

The hydrogenolysis of polymers is emerging as a promising approach to deconstruct plastic waste into valuable chemicals. Yet, the complexity of plastic waste, including multilayer packaging, is a significant barrier to handling realistic waste streams. Herein, we reveal fundamental insights into a new chemical route for transforming a previously unaddressed fraction of plastic waste – poly(ethylene‐co‐vinyl alcohol) (EVOH) and related polymer blends – into alkane products. We report that Ru/ZrO2 is active for the concurrent hydrogenolysis, hydrogenation, and hydrodeoxygenation of EVOH and its thermal degradation products into alkanes (C1−C35) and water. Detailed reaction data, product analysis, and catalyst characterization reveal that the in‐situ thermal degradation of EVOH forms aromatic intermediates that are detrimental to catalytic activity. Increased hydrogen pressure promotes hydrogenation of these aromatics, preventing catalyst deactivation and improving alkane product yields. Calculated apparent rates of C−C scission reveal that the hydrogenolysis of EVOH is slower than low‐density polyethylene. We apply these findings to achieve hydrogenolysis of EVOH/polyethylene blends and elucidate the sensitivity of hydrogenolysis catalysts to such blends. Overall, we demonstrate progress towards efficient catalytic processes for the hydroconversion of waste multilayer film plastic packaging into valuable products. [ABSTRACT FROM AUTHOR]

Highlights Polymer nanocomposites boast complex microstructures with instant control of final performance, including mechanical strength, thermal stability, and crystallinity. Although tremendous studies have been devoted to understanding the structure–property relation of polymer nanocomposites, the effect of simultaneous nanomaterial contents on binary polymers remains unclear. Here, we report how the microstructure and rheological characteristics are subject to change upon adding a hybrid multi‐walled carbon nanotube (CNT) and graphene nanoplatelet (GNP). We choose a refined binary system based on polypropylene (PP) as a commodity polymer with proven long‐standing applications, alongside ethylene‐butylene copolymer (EBC) with a random ethylene and butylene monomers orientation for better impact strength acquisition. Rheology and microscopy imaging support an adequate dispersion of both materials across the PP/EBC blend, similar to when a single‐particle nanocomposite is examined. Beyond investigating the heterogeneous nucleation role of CNT and GNP, the crystallinity rate and the half‐time parameter for completing the ordered transformation are calculated using the Avrami equations. The thermal stability as well as the mechanical properties of all nanocomposites reveal improved resilience under heat and external stress, leading to a rising trend in decomposition temperature, tensile strength, and modulus. Synergistic effect of hybrid CNT and GNP on the thermal stability of PP/EBC. The impact of hybrid CNT and GNP on crystallization kinetics. Improvement of the mechanical performance with CNT/GNP loading. Role of PP‐g‐MA on the dispersion and distribution of CNT and GNP. [ABSTRACT FROM AUTHOR]

Achieving efficient and large‐area organic solar modules via non‐halogenated solution processing is vital for the commercialization yet challenging. The primary hurdle is the conservation of the ideal film‐formation kinetics and bulk‐heterojunction (BHJ) morphology of large‐area organic solar cells (OSCs). A cutting‐edge non‐fullerene acceptor (NFA), Y6, shows efficient power conversion efficiencies (PCEs) when processed with toxic halogenated solvents, but exhibits poor solubility in non‐halogenated solvents, resulting in suboptimal morphology. Therefore, in this study, the impact of modifying the inner and outer side‐chains of Y6 on OSC performance is investigated. The study reveals that blending a polymer donor, PM6, with one of the modified NFAs, namely N‐HD, achieved an impressive PCE of 18.3% on a small‐area OSC. This modified NFA displays improved solubility in o‐xylene at room temperature, which facilitated the formation of a favorable BHJ morphology. A large‐area (55 cm2) sub‐module delivered an impressive PCE of 12.2% based on N‐HD using o‐xylene under ambient conditions. These findings underscore the significant impact of the modified Y6 derivatives on structural arrangements and film processing over a large‐area module at room temperature. Consequently, these results are poised to deepen the comprehension of the scaling challenges encountered in OSCs and may contribute to their commercialization. [ABSTRACT FROM AUTHOR]

The selective conversion of polyethylene (PE), polypropylene (PP), and mixtures of these two polymers to form products with high volume demand is urgently needed because current methods suffer from low selectivity, produce large quantities of greenhouse gases, or rely on expensive, single-use catalysts. The isomerizing ethenolysis of unsaturated polyolefins could be an energetically and environmentally viable route to propylene and isobutylene; however, noble-metal homogeneous catalysts and an unsaturated polyolefin are currently required and the process has been limited to PE. We show that the simple combination of tungsten oxide on silica and sodium on gamma-alumina transforms PE, PP, or a mixture of the two, including postconsumer forms of these materials, to propylene or a mixture of propylene and isobutylene in greater than 90% yield at 320°C without the need for dehydrogenation of the starting polyolefins. [ABSTRACT FROM AUTHOR]

Polymer dielectrics have gained significant usage in electrical engineering due to their unique merits, such as good flexibility, easy processing, and low cost. However, it is a huge challenge that polymer dielectrics maintain high breakdown strength meanwhile high permittivity for enhanced energy density. Here, sandwiched polymer films are constructed for enhanced energy density. Increased permittivity has been achieved via blending BaTiO3@polyfluorosiloxane with a polymer as the top and bottom layer. Furthermore, the neat polymer as the middle layer is without critically sacrificing breakdown strength. The energy storage density increases from 7.8 J/cm3 of the neat polymer to 10.41 J/cm3 of the sandwich structure at 460 MV/m. This research offers a feasible route for fabricating capacitive films with enhanced energy density. [ABSTRACT FROM AUTHOR]

Current transdermal drug delivery technologies, like patches and ointments, effectively deliver low molecular weight drugs through the skin. However, delivering larger, hydrophilic drugs and macromolecules remains a challenge. In the present study, we developed novel transdermal nanoneedle patches containing levofloxacin-loaded modified chitosan nanoparticles. Chitosan was chemically modified with transcutol in three ratios (1/1, 1/2, 1/3, w/w), and the optimum ratio was used for nanoparticle fabrication via the ionic gelation method. The successful modification was confirmed using ATR-FTIR spectroscopy, while DLS results revealed that only the 1/3 ratio afforded suitably sized particles of 220 nm. After drug encapsulation, the particle size increased to 435 nm, and the final formulations were examined via XRD and an in vitro dissolution test, which suggested that the nanoparticles reach 60% release in a monophasic pattern at 380 h. We then prepared transdermal patches with pyramidal geometry nanoneedles using different poly(lactic acid)/poly(ethylene adipate) (PLA/PEAd) polymer blends of varying ratios, which were characterized in terms of morphology and mechanical compressive strength. The 90/10 blend exhibited the best mechanical properties and was selected for further testing. Ex vivo permeation studies proved that the nanoneedle patches containing drug-loaded nanoparticles achieved the highest levofloxacin permeation (88.1%). [ABSTRACT FROM AUTHOR]

Hydrogels as biomaterials possess appropriate physicochemical and mechanical properties that enable the formation of a three-dimensional, stable structure used in tissue engineering and 3D printing. The integrity of the hydrogel composition is due to the presence of covalent or noncovalent cross-linking bonds. Using various cross-linking methods and agents is crucial for adjusting the properties of the hydrogel to specific biomedical applications, e.g., for direct bioprinting. The research subject was mixtures of gel-forming polymers: sodium alginate and gelatin. The polymers were cross-linked ionically with the addition of CaCl2 solutions of various concentrations (10%, 5%, 2.5%, and 1%) and covalently using squaric acid (SQ) and dialdehyde starch (DAS). Initially, the polymer mixture's composition and the hydrogel cross-linking procedure were determined. The obtained materials were characterized by mechanical property tests, swelling degree, FTIR, SEM, thermal analysis, and biological research. It was found that the tensile strength of hydrogels cross-linked with 1% and 2.5% CaCl2 solutions was higher than after using a 10% solution (130 kPa and 80 kPa, respectively), and at the same time, the elongation at break increased (to 75%), and the stiffness decreased (Young Modulus is 169 kPa and 104 kPa, respectively). Moreover, lowering the concentration of the CaCl2 solution from 10% to 1% reduced the final material's toxicity. The hydrogels cross-linked with 1% CaCl2 showed lower degradation temperatures and higher weight losses than those cross-linked with 2.5% CaCl2 and therefore were less thermally stable. Additional cross-linking using SQ and DAS had only a minor effect on the strength of the hydrogels, but especially the use of 1% DAS increased the material's elasticity. All tested hydrogels possess a 3D porous structure, with pores of irregular shape and heterogenic size, and their swelling degree initially increased sharply to the value of approx. 1000% during the first 6 h, and finally, it stabilized at a level of 1200–1600% after 24 h. The viscosity of 6% gelatin and 2% alginate solutions with and without cross-linking agents was similar, and they were only slightly shear-thinning. It was concluded that a mixture containing 2% sodium alginate and 6% gelatin presented optimal properties after gel formation and lowering the concentration of the CaCl2 solution to 1% improved the hydrogel's biocompatibility and positively influenced the cross-linking efficiency. Moreover, chemical cross-linking by DAS or SQ additionally improved the final hydrogel's properties and the mixture's printability. In conclusion, among the tested systems, the cross-linking of 6% gelatin–2% alginate mixtures by 1% DAS addition and 1% CaCl2 solution is optimal for tissue engineering applications and potentially suitable for 3D printing. [ABSTRACT FROM AUTHOR]

Electrically conductive polymeric materials have recently garnered significant interest from researchers due to their potential applications in the biomedical field, including medical implants, tissue engineering, flexible electronic devices, and biosensors. Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is considered the most successful conducting polymer due to its higher electrical conductivity and chemical stability, but it suffers from limited solubility in common organic solvents, poor mechanical properties, and low biocompatibility. An area of tremendous interest is in combining PEDOT:PSS with another polymer to form a blend or composite material in order to access the beneficial properties of both materials. However, the hydrophilic nature of PEDOT:PSS makes it difficult to produce composites with non-polar polymers. In order to overcome these problems, we have specifically designed and synthesized two new sulfonated polyurethanes (PUS) with high sulfonic acid functionality. The two polyurethanes, one water-soluble (PUS1) and one water-insoluble (PUS2), were used to make blends with two commercially available PEDOT:PSS formulations (CleviosTM FET and PH1000). Solvent cast films on glass substrates were made from water-soluble PEDOT:PSS/PUS1 blends while free-standing films of PEDOT:PSS/PUS2 blends were fabricated by compression-moulding. Ethylene glycol was used as conductivity enhancer, which showed an increase in the conductivity by several orders of magnitude in most of the compositions investigated. The highest conductivity of 438 S cm−1 was achieved for the blend with 80 wt% of PEDOT:PSS (PH1000) in PUS1. [ABSTRACT FROM AUTHOR]

The widespread use of poly(lactic acid) (PLA) from packaging to engineering applications seems to follow the current global trend. The development of high-performance PLA-based blends has led to the commercial introduction of various PLA-based resins with excellent thermomechanical properties. The reason for this is the progress in the field of major PLA limitations such as low thermal resistance and poor impact strength. The main purpose of using biobased polymers in polymer blends is to increase the share of renewable raw materials in the final product rather than its possible biodegradation. However, in the case of engineering applications, the focus is on achieving the required properties rather than maximizing the percentage of biopolymer. The presented review article discusses the current strategies to optimize the balance of the key features such as stiffness, toughness, and heat resistance of PLA-based blends. Improving of these properties requires molecular structural changes, which together with morphology, crystallinity, and the influence of the processing conditions are the main subjects of this article. The latest research in this field clearly indicates the high potential of using PLA-based materials in highly demanding applications. In the case of impact strength modification, it is possible to obtain values close to 800 J/m, which is a value comparable to polycarbonate. Significant improvement can also be confirmed for thermal resistance results, where heat deflection temperatures for selected types of PLA blends can reach even 130 °C after modification. The modification strategies discussed in this article confirm that a properly conducted process of selecting the blend components and the conditions of the processing technique allows for revealing the potential of PLA as an engineering plastic. [ABSTRACT FROM AUTHOR]

The International Journal of Molecular Sciences has published a special issue titled "Rational Design and Synthesis of Bioactive Molecules." The issue covers various topics related to rational drug design and provides up-to-date information and recent advances in the field. The articles in the issue discuss the design and synthesis of bioactive molecules for different pharmacological systems and diseases, including cancer, viruses, immune response, and reactive oxygen radicals. The use of computational methods, such as molecular docking and molecular dynamics simulations, is highlighted as a valuable tool in drug development research. The issue also explores the design of new drug candidates with enhanced biological action, the antioxidant properties of flavonoids, the development of sustained-release drug delivery systems, the search for antiviral agents, the discovery of antibiotics with novel structures, and the biotransformation processes of 4'-hydroxychalcones. The special issue aims to provide valuable insights and inspire further research in the rational design of bioactive compounds. [Extracted from the article]

The synthesis of group IV metallocene precatalysts for the polymerization of propylene generally yields two different isomers: The racemic isomer that produces isotactic polypropylene (iPP) and the meso isomer that produces atactic polypropylene (aPP). Due to its poor physical properties, aPP has very limited applications. To avoid obtaining blends of both polymers and thus diminish the mechanical and thermal properties of iPP, the meso metallocene complexes need to be separated from the racemic ones tediously—rendering the metallocene‐based polymerization of propylene industrially far less attractive than the Ziegler/Natta process. To overcome this issue, we established an isomerization protocol to convert meso metallocene complexes into their racemic counterparts. This protocol increased the yield of iPP by 400 % while maintaining the polymer's excellent physical properties and was applicable to both hafnocene and zirconocene complexes, as well as different precatalyst activation methods. Through targeted variation of the ligand frameworks, methoxy groups at the indenyl moieties were found to be the structural motifs responsible for an isomerization to take place—this experimental evidence was confirmed by density functional theory calculations. Liquid injection field desorption ionization mass spectrometry, as well as 1H and 29Si nuclear magnetic resonance studies, allowed the proposal of an isomerization mechanism. [ABSTRACT FROM AUTHOR]

Compatibility between polymers with different glass transition temperatures controls the thermomechanical properties of blends. This work explores the segmental dynamics of poly(methyl acrylate) (PMA) chains when they are blended with polymers of different rigidities and miscibility. Inspired by the intriguing dynamic asymmetry of chains within the interfacial layer of nanoparticles, this study aims to understand dynamic heterogeneity in dynamically asymmetric blends of PMA/poly(methyl methacrylate) (PMMA), PMA/polystyrene (PS), and PMA/poly(ethylene oxide) (PEO) using the differential scanning calorimetry (DSC) and quasi‐elastic neutron scattering (QENS) measurements below and above the glass transition temperature of PMMA or PS. Results revealed that the segmental jump distance of PMA increased on blending due to volume enhancement. The reduced effective diffusivity of PMA in PMMA is attributed to PMMA's enhanced flexibility (lower characteristic ratio, C∞) and superior interaction (lower χ) when compared with the PS environment. The results demonstrate that the chain rigidity and miscibility affect the free volume, interchain cooperativity, and segmental dynamics in dynamically asymmetric blends. [ABSTRACT FROM AUTHOR]

The water absorption characteristics of thermoplastic starch (TPS) reveal its ability to interact with and absorb water, influencing its overall performance in various applications. The introduction of aloe vera (AV) gel into the TPS polymeric matrix film has proven beneficial in enhancing tensile strength but a notable deficiency is observed in lowering water absorption percentage. Therefore, this paper aims to reduce the water absorption of the TPS30AV polymer matrix film by utilizing polyethylene (PE) without reducing the tensile strength performance of the TPS30AV film. The TPS30AV film was produced using melt-blending and hot-press techniques. Six samples were presented consisting of a control film (TPS30AV) and TPS30AV film with different concentrations of PE resins (5%, 10%, 20%, 30%, and 40%). The film's performance was assessed by examining its mechanical properties, water absorption, and water solubility. The finding shows that TPS30AV with 40% PE has the highest improvement in water absorption percentage which reduces from 309.86% to 34.16% but a tremendous decrement in tensile strength performance. However, TPS30AV with 10% PE has the highest tensile strength, 9.65 MPa with a 20.99% improvement in water absorption reduction. The properties obtained for TPS30AV10PE were also good in Young's modulus and water solubility percentage. It shows that the film formulated is comparable with previous studies, and improvement has been achieved. As a conclusion, adding PE improved the polymeric structure of TPS30AV and can be used as a biodegradable food-packaging film. [ABSTRACT FROM AUTHOR]