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[Display omitted] Gradually enhancing afterglow under ambient conditions is generated by embedding a typical class of organic luminogens with ingeniousness lying in their architectures into melamine-formaldehyde polymer. Due to effective intramolecular motion resistance, the resulting material exhibits one of the most excellent polymer-based organic afterglow with a phosphorescence quantum yield (Φphos.) up to 38.31% and a lifetime (τphos.) up to 2.73 s. • Gradually enhancing afterglow under ambient conditions is generated. • Effective intramolecular motion resistance is achieved by host–guest doping. • The material exhibits one of the most fabulous polymer-based organic afterglow. • Locking intramolecular conformation contributes to suppressing nonradiative decay. Tackling the challenge of developing ultralong organic phosphorescence (UOP) materials with a high phosphorescence quantum yield (Φ phos.) and an ultralong phosphorescence lifetime (τ phos.) under ambient conditions is urgently needed. Herein, typical organic luminogens with simple chemical structures, namely, triphenylamine (TPA), 9-phenylcarbazole (PCz), and indolo[3,2,1- jk ]carbazole (ICz), are doped into a melamine–formaldehyde (MF) polymer matrix with a compact three-dimensional covalent network to prepare UOP materials, respectively. Both experiments and theoretical calculations suggest that restricting intramolecular motions to suppress the nonradiative decay of triplet excitons plays a critical role in achieving ultralong room-temperature phosphorescence from organic molecules in polymer matrices. The luminophore ICz with a planar and rigid chemical structure, constructed by locking the molecular conformation of TPA via carbon–carbon single bonds, exhibits a bright organic afterglow with a Φ phos. up to 38.31 % and a τ phos. up to 2.73 s in the MF polymer under ambient conditions, representing one of the most excellent polymer-based organic afterglow materials in comprehensive UOP performance. The gradual enhancement in UOP of the resulting luminescent materials has led to their successful use in multi-level anti-counterfeiting. This work provides an effective strategy for developing organic afterglow materials with both high Φ phos. and τ phos. values. [ABSTRACT FROM AUTHOR]

A solid-state optical limiting filter was fabricated by noncovalently functionalizing a graphene-based nanocomposite with a polymer. Graphene oxide was reduced by varying reducing agent concentration and functionalized with metal oxide nanoparticles to enhance electronic transitions and third-order nonlinear optical characteristics. The nanocomposite was dispersed over the PMMA polymer framework, and thin films with μm-scale thickness were fabricated using the dip coating method. XRD analysis confirmed the wurtzite crystal structure of ZnO nanoparticles and the amorphous nature of PMMA. The carbon structural integrity was analyzed using Raman spectra. Linear optical studies revealed a redshift in the π-π* transition peak in rGO, suggesting enhanced conjugation. Third-order nonlinear refraction and absorption properties were assessed using the Z-scan technique, revealing a switching behavior in nonlinear absorption at different input intensities. An increase in the relative concentration of sp2 domains enhanced the nonlinear absorption. Optical limiting potential, determined using open aperture Z-scan data, yielded a threshold value of 0.066 GW/cm2. This study aims to develop a solid-state optical filter with a high laser damage threshold by adjusting the reduction rate, tuning defect levels, and analyzing its effect on the optical limiting potential. [Display omitted] • Thin film fabrication of noncovalently functionalized rGO/ZnO/PMMA and analysis of its third-order nonlinear optical properties. • The detailed defect analysis was performed using Raman spectra. • The impact of defect density on the nonlinear optical characteristics of the thin film was studied. • Defect-controlled optical limiting filters with high laser damage thresholds were developed. • The intensity-dependent switching in nonlinear absorption behavior was studied using the Z-scan technique. [ABSTRACT FROM AUTHOR]

Electromagnetic interference has surged due to the widespread use of electronic communication technologies in integrated electrical systems. Traditionally, inflexible electromagnetic shielding materials have numerous drawbacks, such as being very brittle, uncomfortable to wear, and inappropriate for use in flexible applications. This review explores the advances in flexible (particularly stretchable and compressible) electromagnetic functional materials-based elastomers and a selection of the remarkable supporting deformable polymer matrixes. Additionally, it provides a comprehensive overview of the appropriate delicate structure and the associated manufacturing progress. Furthermore, it comprehensively outlines inventive uses of flexible shields in the fields of energy, sensing, mechanics, and communication, which extend far beyond electromagnetic protection, as well as their present state of development and prospects. Among them, we provide the first well-rounded overview of reconfigurable shielding devices and propose reconfigurability factors (r) and sensitivity (S) to quantify reconfigurable performance as well. This study diverges from prior studies that mostly concentrated on fulfilling conventional specifications (e.g., thin, lightweight, broad, and strong), and may be characterized as the future age of intelligent, adaptable, integrated shields. [ABSTRACT FROM AUTHOR]

Additive manufacturing is evolving in the direction of carbon fiber 3D printing, a technology that combines the versatility of three-dimensional printing with the exceptional properties of carbon fiber. This work aims to provide a brief review of the main methodologies used in carbon fiber 3D printing, focusing particularly on the two most widespread types: continuous fiber printing and short fiber printing. In the context of continuous fiber printing, the process of embedding a continuous carbon fiber into a polymer matrix will be examined, resulting in the achievement of high-performance lightweight structural components. On the other hand, short fiber printing involves the use of short carbon fibers mixed in turn with polymeric materials, with the advantage of having greater ease of processing and obtaining highly performing components with large-scale economic investments that are lower in cost than additive manufacturing using continuous fiber printing. Furthermore, this work will conduct an evaluation of the mechanical properties of products printed using both technologies, focusing on key aspects, such as strength, stiffness, weight, and resistance to mechanical stress. The specific advantages and challenges associated with each printing technique will also be analyzed.

Background: This article describes a method for non-contact local hyperthermal heating of patient's tissue using inductive electromagnetic radiation. Aim: The aim of the study was a theoretical and experimental assessment of the thermal and electromagnetic parameters of the proposed method based on heating of intraoperatively administered, personal, tissue-replacing applicator using induction magnetic field. Methods: Theoretical estimates of the thermal and electromagnetic parameters of this method were performed based on heat conduction equations. An experimental study of the process was carried out using originally designed laboratory inverter and confirmed theoretical calculations. Results: The performed assessments and calculations confirmed the possibility of creating clinically effective hyperthermia in the removed tumor bed by the method of local non-contact intraoperative hyperthermia. Conclusion: The proposed method can be used both independently and in combination with chemo and radiotherapy, thus reducing the risk of recurrence for locally advanced forms of malignant tumors of the oropharyngeal region after surgical treatment.

The electrical properties of polymer nanocomposites based on dielectric polymer matrices of different types and electrically conductive polymer fillers – polyortotoluidine, polyorthoanisidine and polyaniline have been studied. It is shown that the concentration dependence of the specific conductivity on the content of fillers has a percolation character with a low “percolation threshold”, which depends on the nature of the polymer matrix and polyaminoarene and is 1.7-10.0 vol.%. The calculated critical parameters of electroconductivity are characteristic of the formation of an infinite 3-dimensional cluster of conductivity and indicate a significant influence of the nature of the components and morphology of the material on the charge transfer processes in such systems.

Increasing global environmental problems and awareness towards the utilization of eco-friendly resources enhanced the progress of research towards the development of next-generation biodegradable and environmentally friendly material. The development of natural-based composite material has led to various advantages such as a reduction in greenhouse gases and carbon footprints. In spite of the various advantages obtained from green materials, there are also a few disadvantages, such as poor interfacial compatibility between the polymer matrix and natural reinforcements and the high hydrophilicity of composites due to the reinforcement of hydrophilic natural fibers. This review focuses on various moisture-absorbing and sound-absorbing natural fiber polymer composites along with the synopsis of preparation methods of natural fiber polymer composites. It was stated in various studies that natural fibers are durable with a long life but their moisture absorption behavior depends on various factors. Such natural fibers possess different moisture absorption behavior rates and different moisture absorption behavior. The conversion of hydrophilic fibers into hydrophobic is deemed very important in improving the mechanical, thermal, and physical properties of the natural-fiber-reinforced polymer composites. One more physical property that requires the involvement of natural fibers in place of synthetic fibers is the sound absorption behavior. Various researchers have made experiments using natural-fiber-reinforced polymer composites as sound-absorbing materials. It was found from various studies that composites with higher thickness, porosity, and density behaved as better sound-absorbing materials. [ABSTRACT FROM AUTHOR]

Carbonaceous material, especially carbon nanotubes (CNTs), have incredible properties, such as high thermal and mechanical stabilities, good catalytic and adsorption capabilities. In recent years, hybrid nanocomposites have attained considerable attention, due to the combination of unique organic and inorganic elements in a single material. Hence, these nanocomposites have been employed for various applications, such as drug delivery, sensors, corrosion protection materials, flame retardant additives, and pollutant adsorbent. These nanocomposites can be fabricated through various approaches that include powder metallurgy, solution processing, reaction processing, melt processing, electrochemical, and many more. This present review mainly summarizes the various techniques for the fabrication, separation, and purification of CNTs and their nanocomposites, especially CNTs-based polymer and CNTs-based metals/metal oxides nanocomposites. Besides, effects of CNTs embedded with polymers (such as polypyrrole, poly-aniline, and poly-thiophene, etc.) and metals/metal oxides (such as manganese oxide (MnO2), copper (Cu), gold (Au), platinum (Pt), etc.) and how they can be employed toward innovative devices with fascinating properties for a broad range of applications are thoroughly discussed. Further, , industrial applications of CNTs-based polymer/ metal/metal oxides nanocomposites have been reviewed and discussed. [ABSTRACT FROM AUTHOR]

A self-contained, covert, medicated adhesive patch known as a transdermal patch offers a practical mode of delivery for a range of skin and body problems. Multiple drug administration has several disadvantages including inconvenient administration, the risk of overdose, lack of patient compliance, and drug plasma level fluctuations. Transdermal medication delivery has emerged as a creative means of achieving systemic drug absorption at a predefined rate over an extended period. Its primary benefits are reduced dose frequency, avoiding first-pass metabolism by entering directly into the systemic circulation, suitability for elderly patients who cannot take pharmaceuticals orally, and ability to be self-administered with fewer adverse effects. This review covers general aspects like drug absorption pathways through the skin, the kinetics of drug absorption, different factors affecting the transdermal permeability, various types of transdermal patches, their components, and evaluation parameters. Additionally, some marketed transdermal patches and therapeutic applications of transdermal drug delivery systems have been discussed. Moreover, the article includes various generations of advancements in the transdermal drug delivery system and its future aspect. [ABSTRACT FROM AUTHOR]

Herein, a simple and effective approach has been proposed to enhance the interfacial strength between multiwall carbon nanotubes (MWCNTs) and polymer matrix for improving the dispersion of MWCNTs. In more detail, a soluble polyaniline derivate containing polar group (POMA) was selectively incorporated into the binary blend of poly(amide‐imide) (PAI) and MWCNTs. The surface energy and atomic force microscope measurements suggested that POMA was located at the interface of PAI and MWCNTs. Fourier transform infrared measurement indicated that POMA simultaneously interacted with MWCNTs and PAI by hydrogen bonding and π–π interaction, providing stronger interfacial strength between conductive filler and polymer matrix. As a result, the dispersion of MWCNTs and the surface roughness of PAI composites were obviously improved, which is helpful for charge and load transfer in the PAI/MWCNTs/POMA ternary films. As a result, the conductivity increased by 250% from 13 S m−1 for PAI/MWCNTs binary composites to 48 S m−1 for PAI/MWCNTs/POMA ternary composites, and the tensile strength increased from 52 MPa for PAI/MWCNTs binary composites to 66 MPa for PAI/MWCNTs/POMA ternary composites. These findings imply that polar aromatic polymers with suitable surface energy will be a desirable compatibilizer for optimizing the dispersion of carbon nanotubes in the polymer matrix. [ABSTRACT FROM AUTHOR]

This review focuses on the optimization of the optical performance of polymer/dye blends in which dyes are physically dispersed in polymer matrices. The optimization of the optical performance of polymer/dye blends is discussed in terms of: (i) the preparation procedure of polymer/dye blends (melt processing is considered particularly effective for producing polymer/dye blends with optimal dye distribution); (ii) mechanical and thermal solicitations after polymer/dye blend preparation; (iii) the polymer matrix, whose affinity for the dye and crystallinity affects the optical performance the polymer/dye blend; and (iv) the dye, whose chemical structure and concentration are significant determinants of the optical properties of polymer/dye blends. [ABSTRACT FROM AUTHOR]

Several high‐performance reinforcements may be used in epoxy‐based composites. These commonly undergo chemical and/or physical treatments to enhance their interfacial interactions with polymer matrices. One recent technology comprises the use of ionic liquids (IL) as compatibilizers. This strategy may result in the development of composite materials with greater performance or multifunctional characteristics. Herein, an overview in the area of IL‐modified reinforcements and their effect on epoxy‐based composites is presented. The PRISMA protocol was followed for the review, and the focus of these studies was on the modification of carbon nanotubes, followed by graphene/graphite nanoplatelets and bio‐fillers. The most used IL were those based on imidazolium cation, especially 1‐butyl‐3‐methylimidazolium chloride. In most cases, when IL are used, the reinforcement displays stronger interactions with the epoxy matrix, depending the treatment route employed. Improved interfacial interactions are cited as the main reason for the improvement in the composite mechanical and thermal performances. It was also found that strategies for using low IL content, or routes that enable recovery of the salts after fiber/particle treatment, are still required, as well as the study of the influence of different amounts/types of IL on the structure of fillers and their relationships with the composite properties. [ABSTRACT FROM AUTHOR]

Recently, hydrogels based on natural water-soluble polysaccharides have attracted more and more attention due to their favorable characteristics. The high water-holding capacity, lack of toxicity, and biodegradability of such hydrogels make it possible to develop new materials on their basis for biotechnological, biomedical, pharmacological, and medical purposes. Sodium alginate is a non-toxic natural polysaccharide found in marine algae. It is capable of forming solid gels under the action of polyvalent cations that cross-link polysaccharide chains. Alginate-based products are popular in many industries, including food processing, pharmaceutical, and biomedical applications. Cellulose is the most abundant, renewable, and natural polymer on Earth, and it is used for various industrial and biomedical applications. Carboxymethyl cellulose (CMC) is useful in pharmaceutical, food, and non-food industries such as tablets, ice cream, drinks, toothpaste, and detergents. In this review, various methods for the preparation of the compositions based on sodium alginate and CMC using different crosslinking agents have been collected for the first time. Additionally, the drug release profile from such polymer matrixes was analyzed. [ABSTRACT FROM AUTHOR]

Fiber reinforced polymer composites (FRPCs) are considered as core structure in Multi layered armour systems (MAS) to take advantage of maximum energy absorption, mobility and cost criteria design. In this article, based on the problem defining attribute’s optimal material selection in FRPCs determined by Multiple criteria decisions making (MCDM) approach for considered alternative materials from polymer resin, synthetic and natural fiber. Attribute’s weightage and alternatives priority rank were determined through Fussy-Analytical hierarchy process (F-AHP) and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method. Obtained rank was compared with Preference selection index (PSI) an another MCDM method, for better computational conformity. Selected materials from MCDM approach, simulated for energy absorption ability and damage after impact were studied by considering Cowper-Symonds constitutive materials model using 3D macro shell analysis. Various impact velocities were considered from 3 to 50 m/s for rigid steel impactor directed towards the deformable plate. Parameter like Residual kinetic energy, Residual velocity, Energy absorption ratio after impact were studied numerically. Simulation results in terms of specific energy absorption were compared with the rank obtained in MCDM approach. Among the polymers considered epoxy, polyurethane and polyester found better choice. In fibers hemp and basalt found better materials choice for heterogenous FRPCs design in ballistic armour. [ABSTRACT FROM AUTHOR]

House fly Musca domestica L. is a pest of humans, poultry, and livestock across the world. Dependence on chemical insecticides to contain the flies provided varying results and their continued use has led to development of insecticide resistance. Bioactive compounds in plants are an alternative source to manage M. domestica. Lemon grass, Cymbopogon citratus Stapf essential oil caused fumigant toxicity to eggs (LC50 1.299 mg/dm³) and adults (16.56 mg/ dm³). The C. citratus EO caused larval repellence. Polyvinylpyrrolidone when used as polymer matrix to load C. citratus at 1:1, 1:2, and 1:3 caused toxicity to flies for a longer period as compared to use of EO alone. The EO loaded in polymer matrix had a slower dissipation, EO+ PVP polymer mixed at 1:3 retained over 80% of EO after 72 hr when exposed to 60oC. EO, whilst EO alone without a dispenser dissipated in 3 hr. The biological effect of C. citratus EO on M. domestica can be enhanced for a longer period if loaded into a polymer matrix and this would be an effective strategy to manage M. domestica. [ABSTRACT FROM AUTHOR]

In recent years, technological innovation have emerged to standardize pathology laboratory processes and reduce the handling of diagnostic samples. Among them is an automatic tissue embedding system that eliminates the need for manual activity in tissue paraffin embedding, thereby improving sample preservation. Unfortunately, this system cannot be used for cytological specimens due to the lack of an effective holder to support the procedure steps. In this study, we evaluated the performance of a commercial polymer matrix to enable and standardize the automatic paraffin embedding of cytological material from different organs and sources. Cytological samples from 40 patients were collected on the matrices and submitted for fully automatic workflow preparation, from formalin fixation until paraffin block, using the Sakura embedding system. Our results demonstrated the feasibility of the automated procedure, from loading cytological sample onto the matrix to obtaining the paraffin cellblock, thereby avoiding manual manipulation of cellular material. All samples resulted adequately processed and paraffin-embedded showing satisfactory tissue permeation by processing reagents, optimal preservation of cytoplasmic and nuclear details, and good quality of staining results on paraffin sections. Automated embedding of cytological samples eliminates the risk of lost specimens, reduces laboratory burden, standardizes procedures, increases diagnostic yield, and ultimately improves patients' management., (© 2024 Wiley Periodicals LLC.)

A simple approach to the multiscale analysis of a plain weave reinforced composite made of basalt fabrics bonded to a high performance epoxy resin L285 Havel is presented. This requires a thorough experimental program to be performed at the level of individual constituents as well as formulation of an efficient and reliable computational scheme. The rate-dependent behavior of the polymer matrix is examined first providing sufficient data needed in the calibration step of the generalized Leonov model, which in turn is adopted in numerical simulations. Missing elastic properties of basalt fibers are derived next using nanoindentation. A series of numerical tests is carried out at the level of yarns to promote the ability of a suitably modified Mori–Tanaka micromechanical model to accurately describe the nonlinear viscoelastic response of unidirectional fibrous composites. The efficiency of the Mori–Tanaka method is then exploited in the formulation of a coupled two scale computational scheme, while at the level of textile ply the finite element computational homogenization is assumed, the two-point averaging format of the Mori–Tanaka method is applied at the level of yarn to serve as a stress updater in place of another finite element model representing the yarn microstructure as typical of FE 2 based multiscale approach. Several numerical simulations are presented to support the proposed modeling methodology. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman spectroscopy (SERS) is regarded as a versatile tool for studying the composition and structure of matter. This work has studied the preparation of a SERS substrate based on a self-assembling plasmonic nanoparticle film (SPF) in a polymer matrix. Several synthesis parameters for the SPF are investigated, including the size of the particles making up the film and the concentration and type of the self-assembling agent. The result of testing systems with different characteristics is discussed using a model substance (pseudoisocyanin iodide). These models can be useful in the study of biology and chemistry. Research results contain the optimal parameters for SPF synthesis, maximizing the SERS signal. The optimal procedure for SPF assembly is determined and used for the synthesis of composite SPFs within different polymer matrices. SPF in a polymer matrix is necessary for the routine use of the SERS substrate for various types of analytes, including solid samples or those sensitive to contamination. Polystyrene, polyvinyl alcohol (PVA), and polyethylene are investigated to obtain a polymer matrix for SPF, and various methods of incorporating SPF into a polymer matrix are being explored. It is found that films with the best signal enhancement and reproducibility were obtained in polystyrene. The minimum detectable concentration for the SERS substrate obtained is equal to 10−10 M. We prepared a SERS substrate with an analytical enhancement factor of 2.7 × 104, allowing an increase in the detection sensitivity of analyte solutions of five orders of magnitude. [ABSTRACT FROM AUTHOR]

In this paper, we present an extensive experimental study on the dynamic mechanical properties of composites with polymer matrices, as well as a quantification of the parameters that influence these properties. Polymer-composite matrices make it possible to form any reinforcement arrangement of fibres, particles, and layers, which makes it possible to form composite materials with certain dominant mechanical properties according to the internal arrangement for the application. In this study, we focused on the dynamic properties (i.e., damping parameters, such as the loss factor (tan d), logarithmic decrement (λ), storage modulus (E′), and loss modulus (E″)) of composites with polymer matrices, including parameters such as the fibre material, fabric weaving, fibre orientation, temperature, frequency, particle size, volume of short fibres, and epoxy resin type. If other articles focus on one type of composite and 1–2 parameters, then the benefit of this article lies in our analysis of 8 mentioned parameters in the experimental analysis of 27 different types of composites with polymer matrices. The tested fibre materials were glass, aramid, and carbon; the tested woven fabrics were twill, plain, unidirectional, and satin; the temperature range was from −50 to +230 °C; the frequency was 1 Hz and 10 Hz; the particle size was 0.1–16 mm; the volume percentages of the short fibres were 3, 6, and 12 vol.% of the hybrid polymer composites and the type of polymer matrix. We used the free-damped-vibration method with vibration dynamic signal analysis and the forced-damped vibration of dynamic mechanical thermal analysis for testing. We ranked the parameters that influence the dynamic vibration properties according to the effects. Among sets of results provided in the paper, considering the storage modulus, loss modulus, and loss factor, the best results of the fibre composites were for aramid-fibre-reinforced polymers, regardless of the weave type, with an advantage for unidirectional fabric. The best results of the particle composites were for those with fine filler sizes that incorporated the short fibres. [ABSTRACT FROM AUTHOR]

Due to the structural features and manage ability of the intramolecular structure, branched polymer systems are interesting objects of basic research. Recently, it has been proved that polymers with a dextran core and grafted polyacrylamide chains dextran-polyacrylamide (D-PAA) are effective in photodynamic chemotherapy, which gives confidence in the prospect of drug-nanosystem. This study focuses on the further study of impact hybrid nanocomposites based on branched copolymers of dextran-polyacrylamide in anionic D-g-PAA(PE) form with included gold nanoparticles (AuNP) on reproductive function under conditions of experimental chronic kidney disease (EChKD), on which there no records in academic literature so far. Experiments have been conducted on Albino white laboratory mice (weighing 25–30 g). D-g-PAA(PE) was used as a polymer matrix for in situ synthesis of gold nanoparticles (AuNPs). D-g-PAA consists of dextran core and five grafted PAA chains. Polymer/AuNPs systems contain of AuNPs 2–11 nm in size and have a spherical shape. The treatment of substances was carried out in the following way: D-g-PAA(PE) (10.00 mg/kg), D-g-PAA(PE)/AuNPs (9.78 mg/kg) was introduced intravenously once a day, five times. The model of EChKD was reproduced by immunizing animals with kidney homogenate, four times intraperitoneally according to the scheme of the experiment. Our data suggest that treatment with such nanosystems of gold (gold nanoparticles in the polymer matrix D-g-PAA(PE)) are not critically dangerous for therapeutic use, even on initial stage of chronic kidney disease, when kidney damage is already there, accompanied by impaired filtration and manifested by proteinuria. [ABSTRACT FROM AUTHOR]

Polypropylene and polylactide-based composite fibers have been produced by a melt technology. Long vapor-grown carbon fibers (CNFs) have been used as electrical conductivity fillers. It is clearly shown by experimental methods that the CNFs are evenly distributed in the polymer matrix, orienting themselves along the direction of fiber extrusion and retaining their initial dimensions. It is shown that for composites fibers based on crystallizing (polypropylene) and amorphous (polylactide acid) polymer matrix, the dependence of electrical resistance on the filler concentration is percolation character and can be described as a double Boltzmann function. Four sections are identified on the dependences of the electrical resistance on the filler concentration for composite fibers, and the reasons for this character of this dependence on the formation of electrically conductive circuits are analyzed. Investigated in this work are the PP-based and PLA-based composites filled with carbon nanofibers that can be used as antistatic, shielding materials, or as sensors. [ABSTRACT FROM AUTHOR]

Growing environmental concerns have made more people aware of waste utilization and management. Agro-waste is becoming to be one of the main contributors to the environmental issue. From a circular economy perspective, the agro-waste, such as natural fibers (NFs) as well as natural particulates (NPs) found in various parts of the crop, can be utilized for the development of new materials. In particular, the main problem of utilizing these wastes for blending into the polymer matrix is their hydrophilicity. which results in "low mechanical properties of the" composite. To enable the NFs and NPs to be adhered to the matrix, they have to be treated, whether chemically or physically. Treatments that focus on increasing the hydrophobicity can result in significant enhancement in the adhesion of the NF and NP with the matrix. the focus of the current work is primarily on the modulation of the mechanical properties of the polymer-based composite material arising from treatment to the surfaces of the NF and NP. This review covers the physical properties of several important NFs and NPs, the different types of chemical treatments available; the processing of the NF and NP reinforced thermoplastic composites, and the mechanical properties of the composite materials. [ABSTRACT FROM AUTHOR]

The conceptual directions of creating functional composites based on polymer matrices for metal–polymer systems are considered. An algorithm has been developed to develop a methodology for the implementation of the nanostate phenomenon in materials science and technology of composites and metal–polymer systems. The methodological principles of the implementation of the nanostate phenomenon in materials science and the technology of functional materials based on polymer matrices for metal–polymer systems with high performance characteristics are proposed. [ABSTRACT FROM AUTHOR]

Purpose: Evaluating the potential of gross Linum usitatissimum L. seed mucilage to be used as a drug release retardant. In order to do so, seeds were subjected to a simple and scalable extractive process comprising few stages, without alcohol-based precipitation. Matrix tablets based on hydrophilic polymers are one of the simplest forms of developing modified release systems. Methods: Flaxseeds were added to distilled water at a flaxseed:water ratio of 1:13; the suspension was continuously stirred at room temperature, for 24 h. Flaxseeds were sieved and the gross linseed mucilage was freeze-dried. Subsequently, the sample was analyzed through Fourier transform infrared spectroscopy (IV-TF) at wavelength ranging from 650 to 4000 cm−1. Results: Infrared (IR) spectroscopy analysis has suggested the presence of flaxseed mucilage polymers in the extracted product. Tablets presenting mucilage or HPMC (hydroxypropyl methylcellulose) and tablets without polymer were prepared based on the wet granulation technique. Matrix tablets presenting mucilage or HPMC have shown similar dissolution profiles, as well as similar potential in drug release control. Conclusion: The product extracted from flaxseed under simple conditions, even without undergoing purification process, can have high technological value in the pharmaceutical industry because it has excellent potential to be used as excipient for matrix tablet manufacturing. [ABSTRACT FROM AUTHOR]

Targeted synthesis of C/composite Ni-based material was carried out by the method of matrix isolation. The composite was formed with regard to the features of the reaction of catalytic decomposition of methane. The morphology and physicochemical properties of these materials have been characterized using a number of methods: elemental analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, temperature programmed reduction (TPR-H2), specific surface areas (SSA), thermogravimetric analysis, and differential scanning calorimetry (TGA/DSC). It was shown by FTIR spectroscopy that nickel ions are immobilized on the polymer molecule of polyvinyl alcohol, and during heat treatment, polycondensation sites are formed on the surface of the polymer molecule. By the method of Raman spectroscopy, it was shown that already at a temperature of 250 °C, a developed conjugation system with sp2-hybridized carbon atoms begins to form. The SSA method shows that the formation of the composite material resulted in a matrix with a developed specific surface area of 20 to 214 m2/g. The XRD method shows that nanoparticles are essentially characterized by Ni, NiO reflexes. The composite material was established by microscopy methods to be a layered structure with uniformly distributed nickel-containing particles 5–10 nm in size. The XPS method determined that metallic nickel was present on the surface of the material. A high specific activity was found in the process of catalytic decomposition of methane—from 0.9 to 1.4 gH2/gcat/h, XCH4, from 33 to 45% at a reaction temperature of 750 °C without the stage of catalyst preliminary activation. During the reaction, the formation of multi-walled carbon nanotubes occurs.

A combined experimental and numerical buckling analysis is performed for Carbon nanotube-reinforced composite (CNTRC) laminates under uniaxial in-plane compressive load. A finite element simulation program is developed in MATLAB environment and the recorded buckling responses are verified with the experimental results. Closely aligned numerical and experimental results exhibits that inclusion of 0.3% CNT increases buckling strengths of CNTRC composite laminates, regardless of their geometrical parameters. Clamped edge laminates exhibit higher buckling mode shapes, influenced by aspect ratio and edge restraint. Microscopic analysis of CNTRC's fractured surface under compression shows enhanced buckling strength attributed to CNTs’ bridging and pullout effects in the matrix, suppressing crack initiation and propagation. Field Emission Scanning Electronic Microscope (FESEM) is utilized for this investigation. [ABSTRACT FROM AUTHOR]

[Display omitted] • P4VPMe polymer matrix modulated the electron transfer. • Different aggregate state of porphyrins within P4VPMe polymer matrix influenced electron transfer process. • Enhanced understanding of electron transfer pathways. • Provided implications for artificial photosystems. Drawing inspiration from highly efficient natural photosynthetic systems, we developed an artificial photoinduced electron transfer (PET) system within a poly(N -methyl-4-vinylpyridinium) (P4VPMe) polymer matrix. This system features 5,10,15,20-tetrakis-(4-sulfonatophenyl) porphyrin (TPPS) and its zinc complex (ZnTPPS) as electron donors and methylviologen (MV2+) as the electron acceptor. In the presence of an excess of P4VPMe, ZnTPPS exists as individual molecules rather than self-aggregating, favoring PET. Under these conditions, P4VPMe inhibits the formation of ground-state charge-transfer complex between ZnTPPS and MV2+. This shifts the main PET process from singlet to triplet states. ZnTPPS in an excess of P4VPMe demonstrates over a tenfold increase in catalytic activity for the photoinduced oxidation of MV2+ compared to ZnTPPS alone. [ABSTRACT FROM AUTHOR]

Oral drug administration, especially when composed of mucoadhesive delivery systems, has been a research trend due to increased residence time and contact with the mucosa, potentially increasing drug bioavailability and stability. In this context, this study aimed to develop self-assembly mucoadhesive beads composed of blends of κ-carrageenan and sericin (κ-Car/Ser) loaded with the anti-inflammatory drug indomethacin (IND). We investigated the swelling, adhesion behaviour, and mechanical/physical properties of the beads, assessing their effects on cell viability, safety and permeation characteristics in both 2D and triple-culture model. The swelling ratio of the beads indicated pH-responsiveness, with maximum water absorption at pH 6.8, and strong mucoadhesion, increasing primarily with higher polymer concentrations. The beads exhibited thermal stability and no chemical interaction with IND, showing improved mechanical properties. Furthermore, the beads remained stable during accelerated and long-term storage studies. The beads were found to be biocompatible, and IND encapsulation improved cell viability (>70 % in both models, 79 % in VN) and modified IND permeation through the models (6.3 % for F5 formulation (κ-Car 0.90 % w / v | Ser 1.2 % w/v| IND 3.0 g); 10.9 % for free IND, p < 0.05). Accordingly, κ-Car/Ser/IND beads were demonstrated to be a promising IND drug carrier to improve oral administration while mitigating the side effects of non-steroidal anti-inflammatories. [Display omitted] • The k-Car/Ser/IND beads interact strongly with porcine mucosal mucin in the in vitro assay. • The k-Car/Ser/IND beads demonstrate stability under both accelerated and long-term conditions. • The natural polymer matrix is biocompatible (>90 %) and thermally stable. • IND in the k-Car/Ser blend increased cell viability and altered IND permeation. [ABSTRACT FROM AUTHOR]

Additive manufacturing of composite materials is progressing in the world of 3D printing technologies; composite materials allow the combination of the physical and mechanical properties of two or more constituents to create a new material that meets the required properties of several applications. In this research, the impact of adding Kevlar® reinforcement rings on the tensile and flexural properties of the Onyx™ (nylon with carbon fibers) matrix was analyzed. Parameters such as infill type, infill density and fiber volume percentage were controlled to determine the mechanical response in tensile and flexural tests of the additive manufactured composites. The tested composites showed an increment of four times the tensile modulus and 1.4 times the flexural modulus of pure Onyx™ matrix when compared with that of the Onyx™–Kevlar®. The experimental measurements demonstrated that Kevlar® reinforcement rings can increase the tensile and flexural modulus of Onyx™–Kevlar® composites using low fiber volume percentages (lower than 19% in both samples) and 50% of rectangular infill density. However, the appearance of some defects, such as delamination, was observed and should be further analyzed to obtain products that are errorless and can be reliable for real functions as in automotive or aeronautical industries.

Binary and ternary composites (CM) based on M-type hexaferrite (HF), polymer matrix (PVDF) and carbon nanomaterials (quasi-one-dimensional carbon nanotubes—CNT and quasi-two-dimensional carbon nanoflakes—CNF) were prepared and investigated for establishing the impact of the different nanosized carbon on magnetic and electrodynamic properties. The ratio between HF and PVDF in HF + PVDF composite was fixed (85 wt% HF and 15 wt% PVDF). The concentration of CNT and CNF in CM was fixed (5 wt% from total HF + PVDF weight). The phase composition and microstructural features were investigated using XRD and SEM, respectively. It was observed that CM contains single-phase HF, γ- and β-PVDF and carbon nanomaterials. Thus, we produced composites that consist of mixed different phases (organic insulator matrix—PDVF; functional magnetic fillers—HF and highly electroconductive additives—CNT/CNF) in the required ratio. VSM data demonstrate that the main contribution in main magnetic characteristics belongs to magnetic fillers (HF). The principal difference in magnetic and electrodynamic properties was shown for CNT- and CNF-based composites. That confirms that the shape of nanosized carbon nanomaterials impact on physical properties of the ternary composited-based magnetic fillers in polymer dielectric matrix. [ABSTRACT FROM AUTHOR]

The structure of wind turbine blades (WTBs) is characterized by complex geometry and materials that must resist various loading over a long period. Because of the components' exposure to highly aggressive environmental conditions, the blade material suffers cracks, delamination, or even ruptures. The prediction of the damage effects on the mechanical behavior of WTBs, using finite element analysis, is very useful for design optimization, manufacturing processes, and for monitoring the health integrity of WTBs. This paper focuses on the sensitivity analysis of the effects of the delamination degree of fiberglass-reinforced polymer composites in the structure of wind turbine blades. Using finite element analysis, the composite was modeled as a laminated structure with five plies (0/45/90/45/0) and investigated regarding the stress states around the damaged areas. Thus, the normal and shear stresses corresponding to each element of delaminated areas were extracted from each ply of the composites. It was observed that the maximum values of normal and shear stresses occurred in relation to the orientation of the composite layer. Tensile stresses were developed along the WTB with maximum values in the upper and lower plies (Ply 1 and Ply 5), while the maximum tensile stresses were reached in the perpendicular direction (on the thickness of the composite), in the median area of the thickness, compared to the outer layers where compression stresses were obtained. Taking into account the delamination cases, there was a sinuous-type fluctuation of the shear stress distribution in relation to the thickness of the composite and the orientation of the layer. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) was synthesized using the modified Hummer method. TiO2 nanoparticles, rGO/TiO2, and rGO/TiO2/polymer composites were synthesized using the sol–gel technique. Characterization of the prepared composites was carried out by using TGA, SEM–EDS, XRD, and FTIR. It was determined by SEM analysis that each composite showed a homogeneous distribution. The presence of carbon and oxygen for GO and rGO, the presence of titanium and oxygen for TiO2 particles, and the presence of carbon, titanium, and oxygen for rGO/TiO2 and rGO/TiO2/polymer composites have been proven by EDS analysis. The peaks of each composite have been demonstrated by XRD analysis where they show similar results with the materials that formed the composite. The presence of chemical bonds of Ti–O–Ti, C–O, C–OH, and Ti–O–C was proven with the FTIR results. According to TGA analysis, the initial weight loss occurred up to 100 °C due to the water molecules in the structure of rGO. Rapid weight loss occurred at the decomposition temperature of 480 °C. Above 530 °C, weight loss does not occur at temperatures, and rGO shows stability at 763 °C. From 763 to 900 °C, 95.65% of the rGO is completely decomposed. TiO2 nanoparticles showed weight loss at 80–115 °C. rGO/TiO2 composite showed weight loss at 110 °C and below, at 160–300 °C, and at 650 °C in total in three stages. rGO/TiO2/PVA composite showed weight loss at 40–110 °C, at 250–400 °C, and at 600 °C in total in three stages. rGO/TiO2/PEG composite showed weight loss at 28–196 °C, at 250–350 °C, and at 300 °C in total in three stages. TGA analysis results determined that TiO2 showed 0.43%, rGO/TiO2 14.21%, rGO/TiO2/PVA 71.06% and rGO/TiO2/PEG composite 90.56% weight loss. Acid Black I dye and E.coli bacteria were used to determine the photocatalytic and antibacterial activities of the composites, respectively. The rGO/TiO2/PEG composite showed the best result with 78.85% dye decomposition. And also the rGO/TiO2/PVA composite showed the best result with 78.6% bacteria removal compared to other synthesized composites. Hardness measurements showed that the rGO/TiO2 structure has the best hardness value with 74.34 HV due to the covalent carbon bonds in the rGO structure. [ABSTRACT FROM AUTHOR]

The effect of the content of finely dispersed aluminum and a compatibilizer on the peel resistance of an aluminum foil from the surface of a composite based on low density polyethylene and high density polyethylene is considered. To enhance the compatibility between a filler and polymer matrix, a compatibilizer is used in the form of graft copolymers of polyethylene of various grades with methacrylic acid and maleic anhydride. Copper and aluminum foils are used as a substrate. It is shown that the introduction of a compatibilizer into the composition of the aluminum-filled composites enhances their peel resistance. It has been found that when an aluminum-filled compatibilizer is directly used as an adhesive, the peel resistance of copper and the aluminum foils is considerably increased. Graft copolymers of polyethylene with maleic anhydride exhibit the highest peel resistance. The results of the study of the effect of the pressing temperature on the type of adhesive failure are presented. It is shown that an increase in the pressing temperature results in a mixed type of adhesive failure. It has been experimentally proven that, in percentage terms, the cohesive failure is predominant in composites with graft copolymers used as a polymer matrix. It has been established that a 100% cohesive failure is observed in foil-clad composites pressed at a temperature of 190°C in which a graft copolymer of polyethylene with methacrylic acid or maleic anhydride is used as an adhesive. [ABSTRACT FROM AUTHOR]

The paper is dedicated to the development of effective composite coatings with the use of carbon fillers of different morphology, their research, and application in the broadband frequency range. Electromagnetic loss studies were performed according to international standards ASTM D4935, IEEE-STD-299, and the US Department of Defence standard MIL-STD 461F. The impact of hybrid carbon nanomaterial "graphene/nanotubes" on the electrophysical properties of the composite material has been analyzed. As a result, the research laboratory technologies of production of composite coating on water and non-water (alcohol) basis are developed based on the carbon fillers of various morphology and also magnetite. The shielding properties of most of the created composites are estimated in the frequency range from 50 MHz to 30 GHz. The state enterprise “All-Ukrainian center for standardization, metrology, certification, and consumers’ rights protection” (here and after “Ukrmetrteststandart”) conducted comparative tests of the developed coating (in the form of paint) with a protective coating # 842 MG Chemicals (Burlington, Ontario, Canada) based on silver microparticles. Developed water-based composites can be used for interior decoration, in the formation of electromagnetic screens, thin gradient coatings to protect people from electromagnetic radiation in the microwave range.

Wood-residues and plastic wastes are environmental pollutants. The success of engineered Wood–Plastic Composites (WPCs) as structural materials depends on their properties. The physico-mechanical properties of WPCs from Triplochiton scleroxylon sawdust and post-consumer polyethylene water sachet were assessed. The components (Composite A = 10:90% wood–plastic, B = 25:75% and C = 50:50% by weight) were extruded and moulded into standard dimensions for physical (i.e. water absorption and hardness) and mechanical (i.e. tensile and impact strength) tests. Composite A absorbed the least water (0.02 ± 0.01%) and recorded the greatest hardness (51.40 ± 0.01 N mm−2) compared with Composite C (0.08 ± 0.01% and 40.30 ± 0.04 N mm−2 respectively). Tensile strength ranged from 30.64 ± 0.12 N mm−2 (Composite C) to 34.78 ± 0.09 N mm−2 (Composite B), and the impact from 0.50 ± 0.01 J (Composite C) to 0.90 ± 0.01 J (Composite A). The engineering and utilisation of wood-residue and plastic waste into composites would ease timber over-exploitation and minimise environmental pollution threats, contribute to ease timber over-exploitation and minimise environmental pollution threats. [ABSTRACT FROM AUTHOR]

Conductive polymers represent a promising alternative to semiconducting oxide electrodes typically used in dye‐sensitized cathodes as they more easily allow a tuning of the physicochemical properties. This can then also be very beneficial for using them in light‐driven catalysis. In this computational study, we address the coupling of Ru‐based photosensitizers to a polymer matrix by combining two different first‐principles electronic structure approaches. We use a periodic density functional theory code to properly account for the delocalized nature of the electronic states in the polymer. These ground state investigations are complemented by time‐dependent density functional theory simulations to assess the Franck‐Condon photophysics of the present photoactive hybrid material based on a molecular model system. Our results are consistent with recent experimental observations and allow to elucidate the light‐driven redox chemical processes – eventually leading to charge separation – in the present functional hybrid systems with potential application as photocathode materials. [ABSTRACT FROM AUTHOR]

Aircraft undergoes various low-velocity impacts such as bird strike, runway debris, foreign tools drop, etc. on its structure. Kevlar is widely used in several components and structure of the aircraft as Kevlar is an organic fiber from an aromatic polyamide family. Carbon fiber has advantages like high stiffness and properties like that of kevlar. The present study focuses on the analysis of low-velocity impact properties of kevlar 149-carbon fiber reinforced polymer matrix composite material. In this analysis, kevlar 149-carbon fiber, pure kevlar 149 by 10 layers of laminate and pure carbon fiber by 10 layers of laminate are impacted by ball material with a mass of 8g at velocity of 9m/s. The ball impact on the laminate is simulated using LS-DYNA. The max. principal stress, absorbed energy, velocity and displacement of K149C, CK149, KK149CC, CCKK149, KK149 and CC are obtained and compared with all the six composite laminates. The composite laminate, K149C, proves to be the best laminate for aircrafts as it possesses a higher max. principal stress and lower displacement. [ABSTRACT FROM AUTHOR]

Polymer-metal nanocomposite thin films are versatile materials that exploit the mutualistic impact of the unique attributes of the polymer and metal nanoparticle components, enabling applications in various areas including photonics, sensing and catalysis. Sputtering followed by thermal annealing can produce metal or semiconductor nanoparticle thin films on suitable substrates. We present an optimized protocol for the fabrication of polymer-metal nanocomposite thin films, involving spin-coating of the polymer (poly(vinyl alcohol), polyaniline) film and the sputter-anneal process to form metal (silver) nanoparticles in the polymer matrix. Silver nanoparticle films and the polymer-silver nanocomposite films fabricated are characterized using UV-visible spectroscopy, electron microscopy and X-ray photoelectron spectroscopy. The polymer thin film influences significantly, the size and distribution of the nanoparticles formed within. Poly(vinyl alcohol) film is found to enable the formation of a uniform distribution of relatively small silver nanoparticles, with the annealing carried out at lower temperatures than that commonly used in the sputter-anneal procedure. Significantly, mild oxidation of the bare silver nanoparticles that occur during the annealing process is inhibited by the polymer environment. The nanocomposite formation is shown to bestow stability on the nanoparticles, against aggregation under external stimuli like the electron beam, and temporal changes under ambient atmosphere. Synopsis: Ag-polymer nanocomposite thin films are fabricated by the sputter-anneal process and the specific utility of the polymer matrix in the formation of uniform distribution and stabilization of the small nanoparticles demonstrated. [ABSTRACT FROM AUTHOR]

Currently, research on materials containing magnetic magnetic particles give opportunity to the prepare and study of composites with interesting magnetic features. One possibility for producing such materials is the use of fillers with magnetic properties. The final properties of such composites depend mainly on characteristic polymer matrix. However, the addition of magnetic materials arose use of new technologies. Such builders include the magnetic ferrites. Metal hexaferrites represent well researched group of magnetic materials (Mallick, 1993). Their high values of magnetocrystalline anisotropy and saturation magnetization enable widespread application of these materials as permanent magnets. Low price and excellent chemical stability with suitable magnetic characteristics classified ferrites to one of the most important magnetic materials (Rigbi, 1988). The experimental material used was a composite formed by combining a polymer matrix (linear polyethylene HDPE), and the hard-magnetic strontium ferrite labeled FD 160S as a filler. Composites with different filler contents were prepared from the starting materials. The dependence of viscosity on the content of ferrite filler was determined by rheological measurements. [ABSTRACT FROM AUTHOR]