Structure-property Relationships Research Articles

Morphology and Emulsification of Poly(N-2-(methacryloyloxy) ethyl pyrrolidone)-b-poly(benzyl methacrylate) Assemblies by Polymerization-Induced Self-Assembly.

In this work, a series of amphiphilic diblock copolymers poly(N-2-(methacryloyloxy) ethyl pyrrolidone)-b-poly(benzyl methacrylate) (PNMP m -b-PBzMA n ) were developed by the dispersion polymerization method in ethanol. The polymerization-induced self-assembly (PISA) behaviors were studied systematically, and a comprehensive structure-property relationship was also established. Two distinct PISA tendencies were observed, which was mainly depended on the polymerization degree m of PNMP segment. When m is small such as 39 and 55, morphological transitions from spherical to vesicle-like assemblies via wormlike ones upon increasing n commonly happen regardless of the solid content. Alternatively, spherical assemblies became the sole morphology for PNMP64-b-PBzMA n block copolymers because of the excellent solvophilicity of the PNMP64 segment. Attributing to the amphiphilicity of PNMP m -b-PBzMA n block copolymers, PNMP m -b-PBzMA n assemblies by PISA are a type of excellent Pickering emulsifiers. These assemblies prefer to stabilize O/W Pickering emulsions as confirmed by the confocal laser scanning microscopy method, and the effects of polymerization degree of PBzMA segment or morphologies of PNMP m -b-PBzMA n assemblies are finite.

Pharmacophore Identification and Structure-Activity Relationship Analysis of a Series of Substituted Azaindoles as Inhibitors of Trypanosoma brucei.

Human African trypanosomiasis is among the World Health Organization's designated neglected tropical diseases. Repurposing strategies are often employed in academic drug discovery programs due to financial limitations, and in this instance, we used human kinase inhibitor chemotypes to identify substituted 4-aminoazaindoles, exemplified by 1. Structure-activity and structure-property relationship analysis, informed by cheminformatics, identified 4s as a potent inhibitor of Trypanosoma brucei growth. While 4s appeared to be fast acting and cidal in the in vitro assays, it failed to cure a murine model of infection. Preliminary efforts to identify the potential mechanism of action of the series pointed to arginine kinase, though, as we demonstrate, this does not appear to be the sole target of our compounds. This comprehensive approach to drug discovery, encompassing cheminformatics, structure-potency and structure-property analysis, and pharmacophore identification, highlights our multipronged efforts to identify novel lead compounds for this deadly disease.

Data-driven integration of synthetic representative volume elements and machine learning for improved microstructure-property linkage and material performance in ceramics

Ceramic materials, characterized by their heat resistance, dielectric properties, and mechanical performance, are often compromised by brittleness due to microstructural inclusions. These inclusions, such as defects, secondary phases, and pores, are critically analyzed for their impact on material strength and fracture properties. In this study, the linkage between microstructure and properties in ceramic materials is explored through a methodological approach that combines experimental observations with physics-based and machine learning models. A data-driven approach has been employed, utilizing synthetic Representative Volume Elements (RVEs) derived from X-ray computed tomography scans of ceramics. The methodology involves an automated finite element (FE) simulation process for progressive failure analysis under uniaxial compression and tension. The analysis is conducted using statistical, data-driven, and machine learning techniques, including principal component analysis and k-means clustering, to assess the microstructural features' impact on material performance. The study focuses on the use of RVEs for accurately capturing essential microstructural characteristics and addresses the challenges in developing synthetic models and the limitations of simulation capabilities. The study's findings reveal that less uniform inclusion distribution and a higher standard deviation in inclusion size correlate to lower mechanical performance. By applying data-driven methods, this research contributes to the optimization of material performance and the establishment of structure-property relationships, with a particular emphasis on the influence of inclusions and defects on the mechanical behavior of ceramic materials.

3D MXene architectures for electromagnetic protection

Electromagnetic (EM) pollution is becoming increasingly severe due to the explosive growth of various communication devices. EM protection materials are the key to solving EM pollution. MXenes, by virtue of larger specific surface area, numerous surface functional groups and excellent conductivity, are attracting increasing attention and showing competitive performance in EM protection. By constructing 3D MXene architectures, not only can the EM protection performance be significantly improved, but it can also meet the development needs of lightweight, miniaturization, and portability in the future. In this review, we summarized the methods for preparing 3D MXene architectures applied in the field of EM protection. Then, we comprehensively elaborate on the structure-property relationships of 3D MXene architectures and their applications in microwave absorption (MA) and electromagnetic interference (EMI) shielding. Finally, we discuss the challenges and opportunities in the development of 3D MXene architectures for EM protection.

Strain phase equilibria and phase‐field method of ferroelectric polydomain: A case study of monoclinic KxNa1 − xNbO3 thin films

AbstractKnowledge of the thermodynamic equilibria and domain structures of ferroelectrics is critical to establishing their structure–property relationships that underpin their applications from piezoelectric devices to nonlinear optics. Here, we establish the strain condition for strain phase separation and polydomain formation and analytically predict the corresponding domain volume fractions and wall orientations of, relatively low symmetry and theoretically more challenging, monoclinic ferroelectric thin films by integrating thermodynamics of ferroelectrics, strain phase equilibria theory, microelasticity, and phase‐field method. Using monoclinic KxNa1 − xNbO3(0.5 < x < 1.0) thin films as a model system, we establish the polydomain strain–strain phase diagrams, from which we identify two types of monoclinic polydomain structures. The analytically predicted strain conditions of formation, domain volume fractions, and domain wall orientations for the two polydomain structures are consistent with phase‐field simulations and in good agreement with experimental results in the literature. The present study demonstrates a general, powerful analytical theoretical framework to predict the strain phase equilibria and domain wall orientations of polydomain structures applicable to both high‐ and low‐symmetry ferroelectrics and provide fundamental insights into the equilibrium domain structures of ferroelectric KxNa1 − xNbO3 thin films that are of technology relevance for lead‐free dielectric and piezoelectric applications.

Vaporisation Thermodynamics: Are Triazolium Ionic Liquids a Real Alternative to Popular Imidazolium-Based Ionic Liquids?

New experimental vapour pressures and vaporisation enthalpies of the ionic liquids [2,4-dimethyl-1,2,4-triazolium][NTf2], [2-methyl-4-ethyl-1,2,4-triazolium][NTf2], and [2-ethyl-4-methyl-1,2,4-triazolium][NTf2] were measured using the Langmuir method in combination with the quartz crystal microbalance. New experimental vapour pressures and vaporisation enthalpies of the molecular liquids 1H-1,2,4-triazole, 1-methyl-1,2,4-triazole, 1-ethyl-1,2,4-triazole, and 1H-1,2,3-triazole were measured using the transpiration method. Structure–property relationships between molecular and ionic liquids were studied. These results will facilitate chemical engineering calculations of processes involving ILs.

Statistical Evaluation of Cancer Drugs by QSPR Modeling

The prospect of discovering a cure for cancer has been present for the past two to three decades. Annually, this illness affects approximately 10 million individuals worldwide. Anticancer medications are pivotal in treating cancer and other malignant diseases. In this paper, the physical properties and chemical reactions associated with the anticancer medications of various topological indices (TIs) have been established. Additionally, we have discussed the degree-based TIs and their Quantitative Structure-Property Relationship (QSPR) analysis. In mathematical chemistry, molecular descriptors are essential, particularly for researchers investigating Quantitative Structure-Activity Relationship (QSAR) and QSPR models. The goal of the QSPR study is to establish a mathematical relationship between the properties under investigation (such as boiling point and flash point) and various descriptors related to the molecular structure of the drugs. Furthermore, we show the correlation with the physicochemical properties of anticancer medications.

Controlling Mechanical Properties of Medical-Grade Scaffolds through Electrospinning Parameter Selection.

Electrospinning (ES) is a versatile process mode for creating fibrous materials with various structures that have broad applications ranging from regenerative medicine to tissue engineering and surgical mesh implants. The recent commercialization of this technology for implant use has driven the use of resorbable electrospun products. Resorbable electrospun meshes offer great promise as temporary implants that can utilize the layer upon layer method of additive manufacturing to incorporate porosity as a function of process parameters into a scaffold structure. The interconnected porosity and feature size known to ES have previously been observed to hold great potential for simulating the natural cellular environment of soft tissue. This microstructure, proper degradation kinetics, and mechanical properties combine to provide the design basis for artificial tissue structures that could aid in not only wound healing but also true tissue engineering and regenerative medicine. While current advancement in the field is understood to be limited by material properties, the importance of optimizing mechanical properties with currently available materials should not be overlooked. This work investigated the process parameter effects and interactions that control the structure-property relationship for a range of medical-grade aliphatic polyester materials with a range of intrinsic properties. An ε-caprolactone homopolymer (PCL), l-lactide homopolymer (PLLA), and Lactoflex, a copolymer with intermediate properties relative to the homopolymers, were characterized before, during, and after the additive manufacturing process. The interacting effects of process parameters, distance to collector, and dispensing rate were shown to produce variable-density, nonwoven scaffold structures. The resorbable mesh scaffolds of PLLA, PCL, and Lactoflex demonstrated a broad range of mechanical properties (approximately 1-10 MPa ultimate tensile strength and 5-390 MPa tensile modulus). Postprocessing of scaffolds demonstrated removal of solvents and preservation of micrometer-sized features. Resorbable polymers and electrospinning can produce scaffold materials with excellent features and offer tremendous potential in the field of implantable resorbable devices.

Factor Analysis-Based Selection of Xanthoceras Sorbifolia Bunge Oil as a Promising Bio-Based Lubricant

Abstract With increasing environmental awareness, the demand for bio-based lubricants is escalating, positioning vegetable oils as viable alternatives to traditional industrial lubricants. This study is based on the previously established quantitative structure-property relationship - multiple linear regression (QSPR-MLR) model. Then, it employs comprehensive factor scores to assess and rank the anti-wear properties and oxidation stability of 53 vegetable oils with diverse fatty acid compositions. Xanthoceras sorbifolia Bunge oil (XSBO), derived from woody oil plants renowned for their economic and environmental benefits, emerges as a standout candidate following exclusion of previously reported lubricant types. Comparative evaluations via four-ball friction tests and pressurized differential scanning calorimeter (PDSC) analyses reveal XSBO's antioxidant properties are slightly inferior to mineral oils, poly-a-olefins, and synthetic esters. However, XSBO exhibits superior tribological properties and viscosity characteristics. Supported by computational modeling and laboratory validation, XSBO demonstrates significant promise as a bio-based lubricant, advocating its potential as an ideal replacement for conventional base oils.

Structure-property relationship between different molecular precursors and the final properties of carbon dots: Preparation, characterization and applications as sensors for metal ions

Carbon dots (CDs) have attracted significant attention in recent years due to their interesting properties, such as photoluminescence, biocompatibility, excellent water dispersibility, as well as their potential applications in different fields. Despite these features, the complexity of their photoluminescent properties remains a subject of ongoing research and still presents unresolved questions. In this work, we investigated the preparation of various CDs from different low molecular mass starting materials containing carbon, nitrogen and/or sulfur, using hydrothermal carbonization as the preparation method. The CDs were characterized using various techniques, including TEM, FTIR, photoluminescence, UV–Vis, Raman and XPS. A detailed analysis of the initial reactions between the precursors was conducted, and our main results suggest that the optical properties of the CDs are related to fluorophores formed during the initial Michael condensation reactions between the precursors. This process produces molecular fluorescence, which plays a pivotal role in the photoluminescence properties of the nanoparticles. In addition, two of the obtained CDs were used as selective and sensitive probes for metal ions, achieving a detection limit of 0.58 μM and 0.55 μM. Finally, the findings described here can guide future works in fine-tuning the design of CDs with desired properties and different potential applications.

Structure-property relations in rheology of cellulose nanofibrils-based hydrogels

Hydrogels prepared from self-assembled cellulose nanofibrils (CNFs) are widely used in biomedicine, electronics and environmental technology. Their ability to serve as inks for extrusion-based 3D printing is conventionally evaluated by means of rheological tests. A model is developed that describes the response of CNF gels in small- and large-amplitude oscillatory tests in a unified manner. The model involves a reasonably small number of material parameters, ensures good agreement between results of simulation and observations in oscillatory tests and correctly predicts the stress–strain Lissajous curves, experimental data in hysteresis loop tests, and measurements of the steady-state viscosity. The model is applied to analyze how composition and preparation conditions for CNF gels affect transition from shear thinning to weak strain overshoot in large-amplitude shear oscillatory tests. Based on the model, simple relations are derived for the fractal dimension of CNF clusters and the storage modulus of gels prepared in aqueous solutions of multivalent salts. The validity of these equations is confirmed by comparison of their predictions with observations in independent tests.

Novel singlet fission chromophores: Boron/nitrogen para-substituted acenes

Singlet fission (SF) process has attracted growing attention because of its potential capability to overcome the Shockley−Queisser limit on solar cells. So the raising of new molecule with SF character is crucial for its widespread application. In this work, the structure-property relationships of series of boron and nitrogen para-substituted (para-BN-BN and para-BN-NB) anthracene (A-n and A′-n), tetracene (T-n and T′-n), pentacene (P-n and P′-n) and hexacene (H-n and H′-n) are studied to propose novel strategy of designing SF molecule. Among these structures, the number (n) of central rings between para-(BN)2-substituted six-membered rings can efficiently adjust the area of aromaticity, the diradical characters, which provide the low-lying T1-state energy and further favoring the availability of efficient SF molecules. We hope present work can provide novel design strategies toward the discovery of bright SF chromophores for the application to efficient organic solar cells.

Modular design of Diels-Alder reversible networks for the facile production of highly tunable materials

Covalent adaptable networks (CANs) have attracted significant attention due to their potential to form crosslinked, yet reprocessable networks. Their ability to rearrange upon exposure to specific stimuli, in combination with properties such as self-healing can advance the development of novel materials, including for additive manufacturing. Thorough understanding of structure-property relations and processing potential will aid future application-driven research in network design as well as material selection. Therefore, a multitude of CANs were synthesized herein, by crosslinking epoxide-based oligomers via the furan-maleimide Diels-Alder reaction, to evaluate small systematic variations of (co)monomer composition, crosslinker length/flexibility and crosslinking density as vectors of tuning the CANs' thermomechanical properties. Networks with glass transition temperatures (Tg) spanning from <−40 °C up to >20 °C and Young's Moduli spanning from 0.2 MPa to >500 MPa were readily attainable. Crosslinker length/flexibility had a profound impact on the tensile properties, while changes in backbone composition provided insight into the impact of secondary interactions versus rigid moieties on mechanical performance. Self-healing at ambient conditions was demonstrated for elastomeric networks, with healing efficiency being enhanced when using longer crosslinkers. Finally, a cell viability and metabolic activity assay provided a preliminary in vitro demonstration of the biocompatibility of these materials.

Superlubricity in solid lubricated sliding and rolling contacts

Superlubricity, or near zero friction is a highly desired lubrication state for a wide range of practical applications. Although such application scenarios often involve complex contact geometries, solid lubricant technologies, including previous efforts on achieving superlubricity, are almost entirely in linear sliding test conditions. This report demonstrates an experimental pathway to yield superlubricity in rolling-sliding contact conditions using solid-lubricant materials. Ti3C2X based solid lubricant was tested under complex sliding-rolling conditions at engineering-significant contact pressures. The material's compression and inter-layer shearing result in material reconstruction to pose superlubricity. High-resolution transmission electron microscopy analysis, complemented by multi-scan Raman spectroscopy showed the formation of a robust amorphous tribolayer. This demonstration is expected to not only advance the applied aspects in the development of oil-free solid lubricants but also push the boundaries of fundamental understanding of materials’ structure-property relations across physical states.

Constructing a temperature transferable coarse-grained model of cis-1,4-polyisoprene with the structural and thermodynamic consistency aided by machine learning

Polyisoprene (PI) is a widely used polymer and constructing a systematic coarse-grained (CG) PI model with the structural and thermodynamic consistency with the underlying atomic model over a wide range of thermodynamic conditions is very important for the predictive capability of CG model on overall properties of PI polymer materials and the establishment of their structure-property relationship. However, as the number of tunable CG potential parameters and target properties grows, traditional parameter tuning methods become impractical. In this work, we present a novel approach for determining the optimal CGPI non-bonded potential parameters by employing Particle Swarm Optimization as the calibrator with machine learning-based models trained using molecular dynamics data. The resulting CG model is further augmented with temperature factors through a multistate parameterization approach. This enhancement ensures the model's temperature transferability of structure and thermodynamics in a wide temperature of 150K∼750K.

Face-degree-based topological descriptors of germanium phosphide

In graph theory, topological indices are numerical metrics that give information about a graph’s structural traits. The face index is one such topological index that describes planar networks. Since the discovery of graphene, the genealogy of two-dimensional 2D crystals has expanded and currently contains a large variety that has all logical electrical properties required for nano electronics. Nanotechnology benefits from the use of materials that resemble Dirac, such as silicon, graphite, semiconductors, and germanene, as well as TMDC (phosporene), a transition metal dichalcogenide. In contrast with standard topological descriptors, which are numerical values utilised to characterise molecular structures, the face index presents a potentially more comprehensive method for obtaining structural details. In investigations involving quantitative structure-property relationships (QSPR), this may result in more precise predictions. We calculated the recently created face index of Germanium Phosphide (GeP) and its many shapes, including triangle, rhombus, hourglass, and concentric circles.

Preparation and properties of biomimetic bone repair hydrogel with sandwich structure.

One of the critical factors that determines the biological properties of scaffolds is their structure. Due to the mechanical and structural discrepancies between the target bone and implants, the poor internal architecture design and difficulty in degradation of conventional bone implants may cause several adverse outcomes. To date, many scaffolds, such as 3-D printed sandwich structures, have been successfully developed for the repair of bone defects; however, the steps of these methods are complex and costly. Hydrogels have emerged as a unique scaffold material for repairing bone defects because of their good biocompatibility and excellent physicochemical properties. However, studies exploring bioinspired hydrogel scaffolds with hierarchical structures are scarce. More efforts are needed to incorporate bioinspired structures into hydrogel scaffolds to achieve optimal osteogenic properties. In this study, we developed a low-cost and easily available hydrogel matrix that mimicked the natural structure of the bone's porous sandwich to promote new bone growth and tissue integration. A comprehensive evaluation was conducted on the microstructure, swelling rate, and mechanical properties of this hydrogel. Furthermore, a 3D finite element analysis was employed to model the structure-property relationship. The results indicate that the sandwich-structured hydrogel is a promising scaffold material for bone injury repair, exhibiting enhanced compressive stress, elastic modulus, energy storage modulus, and superior force transmission.

α-Amylase inhibition and antioxidative activities of Marasmius tax sp extract: A combined in vitro and in silico exploration

Marasmius tax sp, belonging to the Marasmiaceae family, is a mushroom species that demands extensive study of its medicinal values with scientific evidence. Mycochemical profiling of methanolic extract of Marasmius sp was performed with Gas Chromatogram-Mass Spectroscopy (GC-MS) and presence of eighteen organic compounds were confirmed. The extract demonstrated promising results in terms of its ability to inhibit α-amylase and scavenge DPPH free radicals, indicating its potential as an antidiabetic and antioxidant. The anti-diabetic property of the mycochemicals was further explored by employing inverse molecular docking analysis for the identified mycochemicals against 18-diabetes associate targets. The inverse docking analysis showed four mycosterol compounds with a strong binding affinity against all the targets, while all 18 compounds displayed considerable binding scores (-6.0 to −10.0 kcal/mol) against three crucial targets responsible for the mode of antidiabetic effect, suggesting the extract to have a multi-target, multi-drug effect in treating diabetes. All the identified mycochemicals were evaluated for their drug-likeness, pharmacokinetics, adverse side effects, and bioactivity. Out of the 18 molecules, 17 were found to be bioactive, with 5 of them showing no predicted adverse effects. Further, the structure-property relationship of the mycosterols have been explored using Density Functional Theory (DFT) based calculations. Frontier molecular orbitals, electrostatic potential surfaces and global descriptor analysis were carried out to understand the stability and chemical reactivity of the selective mycochemcials.

Novel suppressor for damascene copper electrodeposition: Thioether-modified polyether with enhanced adsorption through an adjustable synthesis strategy

The void-free deposition of small-sized and high-aspect ratio interconnect structures requires stronger suppressors than conventional polyethers. In this work, thioether was introduced into polyether to develop novel suppressors with improved adsorption on electrode. The structure of thioether-modified polyether can be easily tailored by choosing proper polyether and thiol compound, thus providing a simple way to regulate electrochemical properties of the suppressor. The electrochemical and copper filling performance related to the molecular structure of novel suppressors were systematically investigated. Thioether-modified polyether, which retains the strong polarizability of typical suppressor and exhibits high resistance to accelerator desorption, can significantly suppress copper deposition on feature sidewalls. This enabled defect-free filling of narrower features at a concentration much lower than the typical usage concentration of suppressor. The modified polyethers with ethylene-propylene-ethylene (EPE) oxide triblock ether chains exhibited higher polarization strength and concentration dependence, facilitating the higher deposition current at the bottom during filling. The length and block ratio of ether chain further influenced the anti-desorption ability of the modified polyether, thereby impacting their suppression on sidewalls, which is crucial in filling process. The convenient structural adjustments for thioether-modified polyether, combined with the derived structure-property relationship, contribute to the development of new suppressors with strong adsorption performance.

Effect of interlayer scan rotation on structure-property relationship of directed energy deposited CoCrNi medium entropy alloy

Laser-based Additive Manufacturing (AM) is sought to be a prevalent technique to synthesize medium to high entropy alloys. However, the anisotropy, temperature distribution, and residual stresses in Laser-based AM are some of the major problems that need to be addressed. The effect of interlayer scan rotation on microstructure, texture evolution, and tensile properties of laser-based directed energy deposited CoCrNi are investigated in this study. The electron backscatter diffraction studies revealed the strong 〈001〉 cubic crystallographic texture along the build direction (YZ-plane) without scan rotation. However, there is no preferred grain orientation observed with interlayer scan rotations. The 〈111〉 fiber texture and 〈111〉〈101〉 fiber texture, respectively, are obtained with 67° and 90° scan rotation strategies. The randomized grain orientation due to fiber texture formation enhanced strength significantly with little improvement in ductility. In addition, the substructure refinement is also observed after incorporating scan rotation. Moreover, the present work suggests that nearly isotropic strength and elongation are obtained with 67° rotations.