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The primary goal of the research is to develop a resilient material for electromagnetic interference (EMI) shielding. This study investigates the mechanical, dielectric, and electromagnetic interference (EMI) shielding properties of a composite material reinforced with biocarbon extracted from abaca bract and pineapple fiber in a rigid vinyl ester matrix. The biocarbon is obtained through a pyrolysis process, ensuring its origin from sustainable sources. The fabrication process involves employing the hand layup method, adhering to ASTM standards for comprehensive characterization. Among the fabricated composites, VB3, featuring 2 vol% of biocarbon and 40 vol% of pineapple mat fiber, stands out for exhibiting superior mechanical properties. It achieves a tensile strength of 143 MPa, flexural strength of 184 MPa, compression strength of 161 MPa, and impact energy of 4.31 J. Conversely, VB4, with a higher volume of biocarbon, experiences a slight reduction in mechanical properties attributed to biocarbon agglomeration, while showcasing an enhanced Shore-D hardness of 82. Silane treatment of both pineapple fiber and biocarbon contributes to improved adhesion in the matrix. In terms of electromagnetic interference (EMI) shielding, VB4 surpasses others, delivering maximum shielding effectiveness with total shielding values of 11.18 dB, 30.53 dB, 54.16 dB, and 65.51 dB for frequency bands at 8 GHz, 12 GHz, 16 GHz, and 20 GHz. Similarly, in dielectric properties, VB4 outperforms other designations with a dielectric constant of 9.8, 7.4, 5.8, 4.5, and dielectric loss values of 0.15, 0.31, 0.42, and 0.5 for the respective frequency bands. Moreover, increased biocarbon content further enhances the hydrophobic behavior of the matrix in VB4, achieving a water contact angle of 97°.These findings highlight the multifunctional capabilities of VB4, demonstrating not only superior mechanical strength and EMI shielding but also enhanced dielectric properties and hydrophobic nature. The comprehensive approach to incorporating biocarbon and pineapple fiber, coupled with silane treatment, contributes to the overall performance and versatility of the composite material. [ABSTRACT FROM AUTHOR]

Silicone rubber is a good candidate as a carrier of small molecules in such applications as drug, fragrance and semiochemical delivery. When one matrix is loaded, the molecular interactions between the molecules and the matrix may affect their release rates. For this reason, it is important to investigate the effects of molecular interactions on release to better develop delivery systems with desirable release rates. In this study, the mass transfer and diffusion coefficients of three model molecules (i.e., octanol, octyl acetate, and octyl butyrate) were determined by monitoring their release from silicone rubber sheets loaded using headspace gas chromatography–mass spectrometry. Differential scanning calorimetry was used to characterize the plasticizing effects and Fourier transform infrared spectroscopy was used to characterize the molecular interactions. It was found that the release of octanol conformed to the Fickian diffusion pattern at 1 wt% initial concentration but deviated as the concentration increased due to hydrogen bonding between octanol and the silanol group of the silica filler. When two small molecules were released simultaneously, the effects of one molecule on the diffusion coefficient of the other differed, a result explained by the competing effects of plasticizing and hydrogen bonding. [ABSTRACT FROM AUTHOR]

Characterized by rapid maturation, short growth cycles, and high strength and toughness, bamboo can be compounded with polymers to produce bamboofiber reinforced polymeric composites (BFRPCs). These composites exhibit corrosion resistance comparable to traditional materials such as glass fiber and carbon fiber composites. Additionally, they possess features like low density, high strength, degradability, and environmental friendliness, with low production costs and strong industrial applicability. This paper reviews the accomplishments in BFRPCs and provides an overview of the production processes for BFRPCs. Furthermore, it summarizes the research status of mechanical properties, moisture absorption characteristics, interface performance, and flame retardancy of these composites. The current issues with BFRPCs were analyzed. Finally, the paper explores future research directions and potential applications of BFRPCs. Highlights: The performance studies on BFRPCs are comprehensively presented.Composite processing of BFPRCs is reviewed.Pros and cons of various types of BFRPCs are analyzed.Overview of the applications of BFRPCs in various domains is presented.Future trends and challenges of BFRPCs are introduced. [ABSTRACT FROM AUTHOR]

Light weight polymer composites have been researched for a long time as potential replacements for metallic materials in every field of engineering. Material scientists are focused on using natural materials as constituents of polymer composite to make it bio-degradable, non-toxic, and safer for the environment. But an obstacle in place for this is the low mechanical properties of the bio-composites. Mechanical properties depend on reinforcement, which can be enhanced to a certain extent using different fiber architectures while introducing into the polymer matrix to develop the composite material. In this study, the various fiber reinforcement architectures are present and their influence on different properties has been discussed. In addition, the evolution in the fiber architecture used in polymer composite have also been discussed. The various difficulties faced have been discussed with possible methods to overcome them. [ABSTRACT FROM AUTHOR]

The following review focuses on the manufacturing and parameterizing of ocular drug delivery systems (DDS) using polymeric materials to create soft contact lenses. It discusses the types of drugs embedded into contact lenses, the various polymeric materials used in their production, methods for assessing the mechanical properties of polymers, and techniques for studying drug release kinetics. The article also explores strategies for investigating the stability of active substances released from contact lenses. It specifically emphasizes the production of soft contact lenses modified with Cyclosporine A (CyA) for the topical treatment of specific ocular conditions. The review pays attention to methods for monitoring the stability of Cyclosporine A within the discussed DDS, as well as investigating the influence of polymer matrix type on the stability and release of CyA. [ABSTRACT FROM AUTHOR]

Modifying the polymer matrix by nanoparticles can be a promising approach to improve the performance of fiber-reinforced polymer (FRP) composites. Organic solvents are usually used for dispersing graphene oxide (GO) well in the polymer matrix. In this study, a green, facile, and efficient approach was developed to prepare epoxy/GO nanocomposites. In situ polymerization is used for synthesizing nanocomposites, eliminating the need for organic solvents and surfactants. By loading just 0.6 wt% of GO into the epoxy resin, Young's modulus, tensile strength, and toughness improved by 38%, 46%, and 143%, respectively. Fractography analysis indicates smooth fracture surfaces of pure resin that changed to highly toughened fracture surfaces in this nanocomposite. Plastic deformation, crack pinning, and deflection contributed to improving the toughness of the nanocomposites. FTIR investigations show that amide bonding was created by the reaction of the carboxylic acid groups in GO with some amine groups in the curing agent during the dispersion processes. [ABSTRACT FROM AUTHOR]

The dramatic changes the world and the expectations of potential users have pushed researchers working in flexible foam pressure sensor (FFPS) fabrication to develop more affordable and high-performance materials. Among various materials, polymer foamed-based nanocomposites are a preferred choice due to their excellent mechanical properties, good chemical properties, and easy control. Moreover, the use of nanofillers such as carbon nanotubes (CNTs), carbon black (CB), and graphene in the polymer matrix has greatly improved the properties of the sensors. Therefore, this review focuses on the recent advances in FFPS by using different types of nanofillers in shape and structure. Accordingly, developments in the fabrication of FFPS, including dip coating, spray coating, sputtering, and in situ polymerization are also discussed. Special attention has been paid to identifying the underlying mechanism to maximize pressure sensing and improve the performance of FFPS. Suggestions for future developments in the area of sensing devices applied in health monitoring are also presented. [ABSTRACT FROM AUTHOR]

Solid-state electrolytes (SSEs) are regarded as crucial materials, thus determining the comprehensive properties of solid-state lithium batteries (SSLBs). However, the existing issues of ion transport and interface limit their further development and application. As the inorganic solid-state electrolytes (ISEs) and polymer solid-state electrolytes (PSEs) both present obvious advantages and defects, the strategy of preparing composite solid-state electrolytes (CSEs) by incorporating inorganic components in polymer matrix is considered an effective way to overcome the above-mentioned problems. Nanowires with high aspect ratios are widely used in CSEs. Moreover, nanowires can not only effectively enhance the mechanical properties and ion transport efficiency of SSEs, but also boost the contact between electrolyte and electrode interface, thereby improving the cycle stability and safety of SSLBs. This review systematically categorized nanowires according to their morphology, function, and Li+ conductivity, and discussed their structural properties and synthesis strategies in detail. Moreover, application examples and mechanisms of nanowires in different polymer matrices are also introduced. In the summary and prospect section, we anticipate the existing challenges and future objectives of nanowires in the future research of CSEs.

ABSTRACTPiezoelectric sensors for underwater sonar require high hydrostatic piezoelectric properties (dh, gh and HFOM), and research is being conducted on various types of piezoelectric composites to improve them. In this study, research was conducted to improve the hydrostatic piezoelectric properties of 1–3 type piezoelectric composites using PZT piezoelectric ceramics and polymers. First, the appropriate material and volume fraction of the piezoelectric ceramic were selected through numerical analysis, and then experimental specimens were produced by applying various porosity of the polymer matrix. As a result of the experiment, it was confirmed that dh increased by 75% as the porosity of the polymer matrix increased. This phenomenon was analyzed to be caused by a change in elastic modulus. In addition, gh and HFOM also increased by 70% and 210% as the porosity of the polymer matrix increased. These results experimentally demonstrated that controlling the porosity of the polymer matrix is useful for improving the hydrostatic piezoelectric properties of type 1–3 piezoelectric composites.

Desulfurization as a pre-treatment technique, of the transportation fuel is peremptory both for upgrading fuel quality for commercial exploitation and reducing the outflow of poisonous sulfur compounds for environmental remediation. This article encompasses the applications of mixed matrix membranes (MMMs) for the desulfurization of transportation fuels. This composite membrane system synergizes viable processability of the polymers and enhanced selectivity of different incorporated fillers. Hence it offers increased thermal stability, mechanical strength, excellent separation, and purification performance over traditional polymeric and inorganic membranes. These composite materials are widely studied for their potential applications in sensing, catalysis, water purification, gas separation, and adsorption. Herein, different types of MMMs with respect to fillers, chemical compositions and fabrication methods are focused and then systematically compiled and discussed the recent trend for the desulfurization of transportation fuels with profound scientific rationale. Finally, future prospects and room for further advancements in the wider spectrum of MMMs are discussed for better applications and adoptability in the processing of fuel oils. This review will assist the researchers working on the large-scale processing of transportation fuels with a single-point source of knowledge and will save ample amount of time as well as contribute into key future research directions. [ABSTRACT FROM AUTHOR]

Piezoelectric sensors for underwater sonar require high hydrostatic piezoelectric properties (dh, gh and HFOM), and research is being conducted on various types of piezoelectric composites to improve them. In this study, research was conducted to improve the hydrostatic piezoelectric properties of 1–3 type piezoelectric composites using PZT piezoelectric ceramics and polymers. First, the appropriate material and volume fraction of the piezoelectric ceramic were selected through numerical analysis, and then experimental specimens were produced by applying various porosity of the polymer matrix. As a result of the experiment, it was confirmed that dh increased by 75% as the porosity of the polymer matrix increased. This phenomenon was analyzed to be caused by a change in elastic modulus. In addition, gh and HFOM also increased by 70% and 210% as the porosity of the polymer matrix increased. These results experimentally demonstrated that controlling the porosity of the polymer matrix is useful for improving the hydrostatic piezoelectric properties of type 1–3 piezoelectric composites. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate polymer composites based on andesite of different dispersion as a filler with different types of polymer matrix for further development of production technology. Varying the types and concentration of mineral fillers of different genesis, including volcanic rocks, is one of the ways to modify polymer composite materials. The choice of filler type is an important factor influencing the structure formation and properties of the resulting composite. At the same time, varying the particle size distribution of the filler and its quantitative ratio with the matrix makes it possible to adjust the performance properties of the resulting composite materials within a wide range. In addition, the surface properties of the filler particles and the chemical nature of the polymer matrix are of great importance. The possibility of expanding the range and increasing the operational reliability of composite materials when using new types of natural raw materials determine the relevance of this research. To achieve this goal, a set of modern methods of physical and chemical analysis and standardised testing of materials was used in the study. The object of the study was composite materials using andesite screenings as a fractionated filler and copolymers as a matrix. Changes in the physical and mechanical properties of the composites were determined by varying the content (55-85 wt.%) and granulometry of the filler and the type of polymeric binder. According to the test results, it is possible to adjust the parameters of the properties of polymer composites, while the range of their changes is as follows: water absorption 2.2-14.9 %, density 1.24-1.96 g/cm3, abrasion 0.005-0.1 g/cm2, elastic modulus 41-83 Pa/mm2, which indicates the prospects of manufacturing and practical use of the obtained wear-resistant composites in construction. [ABSTRACT FROM AUTHOR]

The present review is devoted to the search for the possible methods to synthesize siloxane molecular brushes (MBs). Wide diversity of chemical nature and architectures offered by MBs become possible due to the development of state-of-the-art synthetic methods. The review provided a detailed analysis of the possible synthetic approaches to MBs, their advantages and drawbacks. The possible applications of MBs are also discussed. The facts that siloxane MBs can demonstrate unique properties, can be of interest for practical applications, and the suggested synthetic approaches have prospects for further development were underlined. [ABSTRACT FROM AUTHOR]

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Polymer‐based organic room‐temperature phosphorescent (RTP) materials have recently attracted significant attention. In most of the previous works, 'chemical approaches' were applied to improve the performance of RTP materials, such as designing certain phosphors or selecting specific polymeric matrixes. However, enhancing triplet emission through facile 'physical approaches' is rarely reported. In this study, enhanced RTP emissions of phosphor‐doped polymers are reported by thermal annealing. By doping a difluoroboron β‐diketonate derivative into poly(diacetone acrylamide) (PDAAM), green RTP emissions can be obtained. After thermal annealing at 125 °C for 5 min, the afterglow duration of RTP increases from 2.6 to 5.3 s and also the brightness of RTP emission exhibits a threefold increase. Such post‐treatment is applicable for various polymeric matrixes. The mechanism underlying thermal‐annealing enhanced RTP is investigated. Moreover, it demonstrates that controlled RTP by thermal annealing can be used in information encryption and anti‐counterfeiting. This work provides new insight into the development of organic RTP materials with tunable emissions. [ABSTRACT FROM AUTHOR]

The residual polarization of antiferroelectric ceramics is very small, yet they possess high energy storage density and efficiency. Incorporating antiferroelectric ceramic particles into a polymer matrix is beneficial for improving the energy storage performance of composites. However, excessive amounts of ceramic particles can lead to aggregation within the polymer, resulting in defects and a significant reduction in composite film performance. In this study, the antiferroelectric AgNbO3 is selected as the filler and modified with silane coupling agent KH550. poly(vinylidene fluoride) (PVDF) and polymethyl methacrylate (PMMA) are blended as the matrix, and the energy storage performance of the composite is improved by adjusting the additional amount of PVDF. The structure, dielectric properties, and energy storage properties of the composites are systematically studied. The results show that hydrogen bonds are formed between PVDF and PMMA, and PVDF and PMMA are tightly bonded under the action of hydrogen bonds. The compatibility of PVDF with PMMA is optimal when the mass fraction of PVDF is 30 wt%. Moreover, with the synergistic effect of the antiferroelectric filler AgNbO3, the breakdown strength of AgNbO3/PVDF/PMMA composites reaches 430 kV mm−1, and the energy storage density reaches 14.35 J cm−3. [ABSTRACT FROM AUTHOR]

In this work, the adhesion behavior of chemically treated banana and coir Colombian fibers embedded in polylactic acid (PLA) and unsaturated polyester resin (UPR) matrices was investigated. Both types of fibers were treated with a 5 wt.% sodium hydroxide solution for one hour. The properties of treated and untreated fibers were determined by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and tensile tests. To evaluate the adhesion behavior of the fibers in PLA and UPR matrices, pull-out tests were performed, and the percentage of broken fibers was determined. The results showed that alkaline treatment improved the fibers' physicochemical, mechanical, and thermal properties. In addition, the alkaline treatment was able to improve the adhesion behavior of coir and banana fibers to PLA and UPR matrices. The banana fibers showed a percentage of broken fibers of 100%, while the coir fibers showed a slight increase in IFSS value. This behavior is attributed to the improvement in surface roughness due to the removal of non-cellulosic composites and impurities. [ABSTRACT FROM AUTHOR]

It is known that ceramic–polymer composite materials can be used to manufacture spherical bodies in the category of balls. Since balls are frequently subjected to compression loads, the paper presents some research results on the compression behavior of balls made of ceramic composite materials with a polymer matrix. The mathematical model of the pressure variation inside the balls highlights the existence of maximum values in the areas of contact with other parts. Experimental research was carried out on balls with a diameter of 20 mm, manufactured by 3D printing from four ceramic–polymer composite materials with a polymer matrix: pottery clay, terracotta, concrete, and granite. The same ceramic–polymer composite material was used, but different dyes were added to it. A gravimetric analysis revealed similar behavior of the four materials upon controlled heating. Through the mathematical processing of the experimental results obtained by compression tests, empirical mathematical models of the power-type function type were determined. These models highlight the influence exerted by different factors on the force at which the initiation of cracks in the ball materials occurs. The decisive influence of the infill factor on the size of the force at which the cracking of the balls begins was found. [ABSTRACT FROM AUTHOR]

The effect of calcium carbonate nanoparticles (CaCO3) on the mechanical and thermal properties of various polymers was investigated in this review. The results were compared to scholarly research published between 2002-2022. Different polymers were evaluated, including Polypropylene (PP), High-density polyethylene (HDPE), Polyvinyl chloride (PVC), Low-density polyethylene (LDPE), Polyethylene (PE), and natural rubber (NR). Through this work, the effect of CaCO3 nanoparticles that act as fillers in polymeric materials has been reviewed. It can be concluded that mechanical and thermal properties can be decreased, increased, or unchanged by increasing and decreasing the fillers to obtain optimal results. It is reasonable to conclude that most papers with nano-CaCO3 showed improvements in appreciable mechanical and thermal properties. In general, the term "surface modification of inorganic fillers" refers to the coating of the fillers with organic materials, which can be done by physical and chemical interactions between the modifiers and the fillers. The reviewed articles revealed that modification of CaCO3 nanoparticles with surface pre-treatment fillers caused enhancement of the mechanical properties of the polymeric matrix twice and prevented the agglomeration of particles in the matrix. Various mixing methods have been used, the most significant being a twin screw extruder, mechanical stirrer, and two-roll mill.

In this paper, the relaxation isomerization properties of a spiropyran-doped poly(methyl methacrylate) (PMMA) UV light-responsive dynamic material are presented. The polar liquid (acetonitrile) and solid (PMMA matrix) medium may contain two merocyanine isoforms of the selected spiropyran. A complex equilibrium of the colored and colorless spiropyran isoforms resulted in specific transformations of the absorption spectra during the relaxation process. Bands at 522 nm and 580 nm characterized the absorption of the fabricated dynamic material in the ground (non-activated) state in the visible range. The presence of colored and colorless isoforms of spiropyran incorporated into the PMMA matrix using Raman spectroscopy was revealed. The photosensitive polymer samples were irradiated with a UV LED (365 nm and 390 nm) under various temperatures (0–30 °C). Spectral changes within the relaxation process demonstrated their complex dynamics. Surprisingly, the photodegradation of the dynamic material was estimated at about 25% (using 390 nm) and 7% (using 365 nm) after eight photoswitch cycles for one isoform, and no fatigue after an additional one (using 390 nm) was discovered. The presented light-responsive material is of interest for UV sensors and new hybrid material design. [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. [ABSTRACT FROM AUTHOR]

As a key material for capacitors, high-performance polymer dielectric films still exhibit the problem of low energy storage density, which cannot meet the requirements of high-power and high-temperature conditions. Here, a sandwich-structured composite film with inner layer doped TiO2-BCB (titanium dioxide – benzocyclobutene) and outer layer doped BN-BCB (boron nitride – benzocyclobutene) nanoparticles was prepared, which exhibits reduced dielectric loss, leakage current and enhanced dielectric constant (ε) and breakdown strength (Eb). Diels-Alder reaction and radical polymerization reactions are utilized to form the entire cross-linked sandwich structure. Moreover, the thermal-induced crosslinked structure replaces the traditional multilayer structure established by Van der Waals forces, thus improving the dielectric and mechanical qualities of the film. Specifically, the sandwich structure composites achieved a large discharge energy density (4.0 J/cm3) and high charge-discharge efficiency (84%) at 150 °C and 450 MV/m, and the dielectric dissipation factor is less than 0.005. These results demonstrated that designing a cross-linked network in multilayer nanocomposite structure is a feasible method to improve the high-temperature energy storage performance of these films. [ABSTRACT FROM AUTHOR]

This comprehensive review explores the multifaceted world of natural fiber applications within the domain of composite materials. Natural fibers are meticulously examined in detail, considering their diverse origins, which encompass plant-derived fibers (cellulose-based), animal-derived fibers (protein-based), and even mineral-derived variations. This review conducts a profound analysis, not only scrutinizing their chemical compositions, intricate structures, and inherent physical properties but also highlighting their wide-ranging applications across various industries. The investigation extends to composites utilizing mineral or polymer matrices, delving into their synergistic interplay and the resulting material properties. Furthermore, this review does not limit itself to the intrinsic attributes of natural fibers but ventures into the realm of innovative enhancements. The exploration encompasses the augmentation of composites through the integration of natural fibers, including the incorporation of nano-fillers, offering a compelling avenue for further research and technological development. In conclusion, this review synthesizes a comprehensive understanding of the pivotal role of natural fibers in the realm of composite materials. It brings together insights from their diverse origins, intrinsic properties, and practical applications across sectors. As the final curtain is drawn, the discourse transcends the present to outline the trajectories of future work in the dynamic arena of natural fiber composites, shedding light on emerging trends that promise to shape the course of scientific and industrial advancements. [ABSTRACT FROM AUTHOR]

End of life tires (ELTs) are a pressing environmental concern due to their non-biodegradable nature and potential release of toxic chemicals, as confirmed by human health exposure studies. The expanding transport sector, driven by the automotive industry, has led to inadequate attention to safe tire disposal. This review extracted papers using keywords such as "waste tire rubber," "waste tire pollution," and "waste tire applications" from 2012 to 2023. Recycling publications have surged by 80% in the past decade, with China and the USA leading the research. Pyrolysis and devulcanization methods have emerged as key circular economy (CE) advancements, producing fuel and reusable rubber. Globally, 1.5 billion waste tires accumulate yearly, projected to increase by 70% in the next 30 years if unaddressed. Around 26 million tonnes of used tires are generated annually worldwide, while civil engineering and backfilling use 17 million tonnes of recycled rubber particles. These tires are complex polymer composites, primarily composed of natural and synthetic rubber. The amorphous nature of rubber results in a 50% loss of mechanical properties when exposed to chemicals and microbes, shortening its lifespan. This paper explores the applicability of waste tire rubber and polymer fabrication to offer eco-friendly and cost-effective solutions for proper disposal, mitigating environmental accumulation. [ABSTRACT FROM AUTHOR]

The hybridization of SiC filler and synthetic fiber in a polymer matrix composite has great potential to improve radiation shielding, strength, hardness, and thermal stability. In this work, SiC particle-filled Kevlar/Jute/Epoxy hybrid composite was fabricated using the hand-lay-up technique for the first instant. The effect of SiC filler was investigated in five different laminates (JKKJ-5%, JKKJ-10%, JKKJ-15%, JKKJ-20%, and JKKJ-25%) with varying SiC weight %. Properties like tensile, flexural, impact strength, thermal conductivity, and thermal resistance were analysed. Finally, the fractured specimen was analysed using scanning electron micrographs. The tensile, flexural, and impact strength was maximum for JKKJ-10%, JKKJ-5%, and JKKJ-25% specimens, respectively. Increased SiC filler reduced the thermal conductivity and improved the thermal resistance to 20 filler wt %. The SEM fracture morphology revealed that fiber pull-out, fiber failure, micro voids due to air entrapment, entrapped bubbles, and out-off-plane shear failure were the majorly observed failure mechanism. Considering all the fabricated Kevlar/Jute/SiC/Epoxy laminates, the JKKJ-10% specimen showed the best average mechanical and thermal properties. [ABSTRACT FROM AUTHOR]

Rapid advancements in the field of 3D printing in the last several decades have made it possible to produce complex and unique parts with remarkable precision and accuracy. Investigating the use of 3D printing to create various high-performance materials is a relatively new field that is expanding exponentially worldwide. Automobile, biomedical, construction, aerospace, electronics, and metal and alloy industries are among the most prolific users of 3D printing technology. Modern 3D printing technologies, such as polymer matrices that use fiber-reinforced composites (FRCs) to enhance the mechanical qualities of printed components greatly, have been useful to several industries. High stiffness and tensile strength lightweight components are developed from these materials. Fiber-reinforced composites have a wide range of applications, such as military vehicles, fighter aircraft, underwater structures, shelters, and warfare equipment. Fabricating FRCs using fused deposition modeling (FDM) is also advantageous over other 3D printing methods due to its low cost and ease of operation. The impact of different continuous fiber and matrix polymer selections on FRC performance is covered in this review paper. We will also evaluate the important parameters influencing FRC characteristics and review the most recent equipment and methods for fabricating FRCs. Furthermore, the challenges associated with 3D printing fiber-reinforced composites are covered. The constraints of present technology have also been used to identify future research areas.

In recent years, there has been a notable surge in research focusing on the use of natural fiber-reinforced polymer composites (NFRPCs) in the automobile industry. These materials offer several advantages over their synthetic counterparts, including lightweight properties, renewability, cost-effectiveness, and environmental friendliness. This increasing research interest in NFRPCs within the automotive sector is primarily aimed at overcoming the challenges that have thus far limited their industrial applications when compared to conventional synthetic composites. This paper provides a comprehensive overview of the potential applications and sustainability of lignocellulosic-based NFRPCs in the automobile industry. It examines the current state of knowledge, identifies research needs and existing limitations, and provides insights into future perspectives. This review shows that, while lignocellulosic fibers hold great promise as sustainable, high-performance, and cost-effective alternatives to traditional reinforcing fibers, continuous research is needed to further address issues such as fiber-matrix compatibility, processing techniques, long-term durability concerns, and general property improvement. These advancements are essential to meet the increasing performance demand for eco-friendly, renewable, and energy-efficient materials in automotive design.

Carbon-based nanoparticles (CBNs) are regarded as promising nanofillers in nanocomposites to produce high-performance fiber-reinforced polymers (FRPs). To date, no systematic investigations have been carried out on the structural variations of nanofillers and their influences on dispersion characteristics, which give nanocomposites their mechanical and durability properties. Moreover, environmentally unfriendly organic solvents are used to exfoliate and disperse CBNs in a polymer matrix. This study developed a green, easy approach to preparing epoxy/CBN nanocomposites. We demonstrated graphene oxide’s (GO) effective dispersion capacity, creating good interface interaction that dramatically influenced properties at loadings as low as 0.4 wt%. The tensile strength and toughness of the epoxy increased by about 49%; and 160%, respectively. Incorporating 0.4 wt% of multi-wall carbon nanotubes (MWCNTs), graphene nanoplates (GNPs), or GO into the epoxy increased the modulus storage by around 17%, 25%, and 31%, respectively. Fractography analysis of fracture surfaces indicated the primary reinforcing mechanisms (crack deflection and penning) as well as the secondary mechanism (bridging effect) enhancing the mechanical characteristics of nanocomposites. Incorporating GNPs, GO, or MWCNTs into the epoxy decreased the water absorption at saturation by about 26%, 22%, and 16%, respectively.

Modifying the polymer matrix by nanoparticles can be a promising approach to improve the performance of fiber-reinforced polymer (FRP) composites. Organic solvents are usually used for dispersing graphene oxide (GO) well in the polymer matrix. In this study, a green, facile, and efficient approach was developed to prepare epoxy/GO nanocomposites. In situ polymerization is used for synthesizing nanocomposites, eliminating the need for organic solvents and surfactants. By loading just 0.6 wt% of GO into the epoxy resin, Young’s modulus, tensile strength, and toughness improved by 38%, 46%, and 143%, respectively. Fractography analysis indicates smooth fracture surfaces of pure resin that changed to highly toughened fracture surfaces in this nanocomposite. Plastic deformation, crack pinning, and deflection contributed to improving the toughness of the nanocomposites. FTIR investigations show that amide bonding was created by the reaction of the carboxylic acid groups in GO with some amine groups in the curing agent during the dispersion processes.

The following review focuses on the manufacturing and parameterizing of ocular drug delivery systems (DDS) using polymeric materials to create soft contact lenses. It discusses the types of drugs embedded into contact lenses, the various polymeric materials used in their production, methods for assessing the mechanical properties of polymers, and techniques for studying drug release kinetics. The article also explores strategies for investigating the stability of active substances released from contact lenses. It specifically emphasizes the production of soft contact lenses modified with Cyclosporine A (CyA) for the topical treatment of specific ocular conditions. The review pays attention to methods for monitoring the stability of Cyclosporine A within the discussed DDS, as well as investigating the influence of polymer matrix type on the stability and release of CyA.

The food industry produces an exorbitant amount of solid waste of petrochemical origin as a result of the increase in the development of new products. Natural polymers are an alternative to this theme; however, their development with adequate properties is a challenge. The union of different polymers in the synthesis of packaging is usually carried out to improve these properties. The combination of agar-agar and chitosan biopolymers show particular advantages through hydrogen bonds and electrostatic attraction between oppositely charged groups, presenting a promising source of studies for the synthesis of green packaging. When combined with natural extracts with active properties, these polymers allow an increase in the microbiological stability of foods associated with lower chemical preservative content and greater environmental sustainability.

This paper considers a method for determining the type of electrical conductivity of a previously developed composite transparent conductive coating based on oriented platinum networks embedded in the polymer matrix. Many researchers have recently been grappling with finding electrically conductive transparent coatings for smart devices with touch screens, particularly an alternative to the massively used indium tin oxide (ITO) having some disadvantages, the most serious of which is the lack of coating flexibility. The latter can be overcome by using various metal-polymer composites with high transparency in the optical range and low surface resistance. However, one should be aware that the type of conductivity depends on both the polymer matrix and the metal framework of a composite. This defines its electrical properties. Therefore, it is important to correctly identify and measure the electrical conductivity. The developed method is based on studying the temperature dependence of the surface resistance in the material.

The usual replication method for preparing open-pore metal foams using NaCl as a template cannot be successfully applied to the fabrication of foams using either water-based ceramic slurries in which NaCl can be dissolved during processing, or liquid polymers that wet NaCl and leave no interconnecting windows between pores. In this work, we propose to modify the replication process by including a second template, paraffin, which is deposited over the NaCl and serves a dual purpose: (i) it acts as a barrier to dissolution of the NaCl with the matrix precursor, and (ii) it creates size-controllable binding collars between the particles that ensure the formation of interconnecting windows in the foam. The usefulness of the process described here is illustrated by the fabrication of two types of materials: low porosity epoxy and cement matrix foams and Guefoams. As proof of concept, epoxy-based Guefoams were developed for the removal of Escherichia coli in water using iodine-impregnated activated carbon particles as the guest phase. The results indicate that the Guefoams outperform conventional bactericidal particle beds in several aspects, including their ease of handling and their tunable fluid-dynamic properties that enable high bacteria annihilation efficiency.

Dielectric spectroscopy (frequency range f = 100...107 Hz and temperatures T = 293...403 K (accuracy 0.5 K), measuring voltage applied to the sample was 1.0 V) was used to study composite materials based on perfluorosulfonic membranes with inclusions of rare-earth elements, in particular, europium (III) and terbium (III) chlorides. The dispersion of the permittivity and the presence of maxima, corresponding to losses, were revealed, which indicates that relaxation processes of various natures were present. The membrane layers under investigation are characterized by relaxation parameters that correspond to a symmetrical distribution of relaxers over relaxation times. The spectrum of relaxers changed when terbium and europium metal impurities were introduced into the polymer matrix. The investigation of these polymer systems demonstrated a power-law dependence of the specific conductivity on frequency. A decrease in the exponent with increasing temperature indicates the existence of a traditional hopping mechanism for charge transfer. The observed changes in the dielectric permittivity and specific conductivity are due to a change in the nature of polarization processes because of the strong interaction of metal (terbium and europium) ions with the polymer matrix of Nafion. [ABSTRACT FROM AUTHOR]

Poly (vinyl acetate) (PVAC) based on Algerian clay maghnite was synthesized by an emulsion polymerization process in the present study. The prepared nanocomposites were analyzed by means of FTIR, UV‐visible, XRD, AFM, SEM, TGA and optical microscopy. The results obtained showed a semi‐crystalline structure of the composite system revealed by the XRD scheme. The addition of maghnite to the fillers up to 5 wt % has been shown to reduce the optical band gap energy, while the refractive index is greatly increased. The presence of maghnite in PVAC leads to an increase in surface roughness as measured by AFM analysis. The thermal stability of PVAC was significantly improved by the presence of maghnite in the polymer matrix. The mechanical test results indicate that the tensile strength of the polymer composites was improved by the increase in the concentration of clay platelets. The electrical property data show that as the frequency increases, the dielectric constant decreases and the electrical conductivity increases. The loading content of composites also influences their electrical and mechanical properties. This widens the range of applications for these materials in flexible electronics and in conductive coatings. [ABSTRACT FROM AUTHOR]

The effect of the concentration of technical carbon on the peel resistance of nanocomposites based on low-density polyethylene, high-density polyethylene, polypropylene, a compatibilizer, and polyolefins filled with 5.0 wt % aluminum and copper is considered. High density polyethylene modified with maleic anhydride and propylene are used as a compatibilizer. The concentration of technical carbon is varied in the limits of 0–40 wt %. It has been established that polyolefin nanocomposites with 5–15 wt % technical carbon exhibit relatively high peel resistance. The main factors affecting the formation of an adhesion contact have been found. [ABSTRACT FROM AUTHOR]

This research paper presents the results of an investigation into the formulation of silver conductive ink for use in inkjet printing. The aim of the study is to develop an environmentally friendly and cost-effective ink using a simple and scalable method. To achieve this, silver nanoparticles (AgNPs) were synthesized through a co-reduction approach using starch and temperature, and their physical and chemical properties were examined. The silver conductive ink was prepared with different amounts of AgNPs, using a sodium alginate/ Polyethylene glycol (Na-alginate/PEG) suspension matrix. In order to ensure the suitability of ink for the inkjet printing technique, the viscosity measurement was performed. According to the results, three formulations were produced and printed on Polyurethane-coated polyester (PU-coated PET) by a syringe disposition system. The electrical measurements showed that the minimum sheet resistance of printed patterns prepared with 3%wt of AgNPs was 0.008 Ω/cm and 0.205 Ω/cm with 20wt% and 40wt% of Na-alginate, respectively. These values are sufficient to power an LED connected to the printed coated fabric. Furthermore, the electrical properties of the printed patterns remained acceptable for electronic applications even after mechanical stress up to 20%. This research has the potential to pave the way for several future applications of printed electronic textiles where environmentally friendly, low-cost, and higher electrical performance inks are required. [ABSTRACT FROM AUTHOR]

Linear low-density polyethylene (LLDPE) is a commodity material that has been increasingly used in various open environments owing to its versatile properties. The mechanical and thermal degradation and processability properties can be enhanced by blending with other polymers or using different types of fillers to adjust such properties to fit the required applications. The objective of this work is to investigate the polymer–polymer interface and compare it with the polymer–additive (microparticles) interface in terms of structural changes and the impact on the polymer environmental properties. The novelty of this work is how to control the adhesion at the interface to enhance selected properties of the polymer without compromising other properties. LLDPE dried resins were compounded with UV additive and different wt% content of LDPE resin separately in a twin-screw extruder at 180–200°C and 150 rpm rotating speed with a die head to produce 1 mm thickness sheets. Then the prepared specimens were cooled to ambient temperature for testing. The nuclear magnetic resonance results showed that LLDPE with microparticles has good phase adhesion compared to the blended samples with LDPE. Moreover, thermal gravimetric analysis showed that the blends decompose in two steps at high LDPE content. The morphological images revealed cavities in the microstructure of low weight percent blends inductive of the relatively weak interaction between the components. The present study conclusively demonstrates that the polymer matrix is more stable with microparticle fillers (UV stabilizer) additive than with LDPE, which impacts the environment durability for outdoor application.

Marine fouling is a widespread problem in the maritime industry, causing significant damage to equipment and vessels. Polybenzoxazine (PBz) is a resin that is both remarkable and captivating, and it has a wide range of sophisticated uses. Due to their distinctive characteristics, benzoxazines have sparked the interest of scholars globally. However, most benzoxazine resin production and processing depend on petroleum resources, particularly those based on bisphenol A. This study aimed to create new benzoxazine monomers using bio-based raw materials, primarily motivated by the environmental ramifications. The main goal of this study is to synthesize a benzoxazine molecule, specifically (2E,6E)-2,6-bis(3-(2-hydroxyethyl)-3,4-dihydro-2H-benzo[e][1,3]oxazin-6-yl)methylene) cyclohexane-1-one, abbreviated as (CHPE), by employing an arylidene base. Later, the chemical was used as a modifier for the cellulose acetate (CA) matrix to create film samples. The primary objective is to evaluate the effectiveness of these film samples in preventing fouling. The CHPE molecule was produced using a bis(arylidene) cyclohexanone diol and analyzed using Fourier transform infrared (FTIR) and Nuclear magnetic resonance (NMR) spectroscopic techniques, respectively. The films were fabricated by blending various weight proportions. The composition of the (CHPE-CA) films was determined by FTIR analysis, while their morphology was examined using scanning electron microscopy (SEM). The thermal stability of the films was studied using Thermal Gravimetric Analysis (TGA). This study investigated the antifouling properties of polymer sheet compositions containing varying amounts of CA at two different processing temperatures, 180 °C and 200 °C and without curing. The results demonstrated the potential of incorporating CA into the polymer matrix to enhance antifouling performance. Among the polymer compositions tested, the 20% CA composition exhibited the highest percentage reduction in fouling at both processing temperatures, suggesting that a small amount of CA can contribute to effective antifouling properties.

This work investigates the impact of several polymer matrix types, which are utilised as a capping layer around gold particles, on the optical properties. Nanocomposite materials consisting of gold and polymers such as polyethylene oxide, polyvinyl alcohol, and polyvinyl pyrrolidone were produced by a chemical reduction process. Tri sodium citrate was employed as the reducing agent. using the drop casting approach, nanocomposites based on gold were successfully put as a film on glass substrates.. An investigation was conducted to determine the influence of the polymer matrix type on the optical properties, including surface plasmon resonance, direct band gap, and indirect band gap. Furthermore, the absorption spectra of the materials that were synthesised demonstrated that the selection of the polymer that was utilised during the preparation process has a considerable impact on the location of the plasmonic absorption peak as well as the magnitude of the energy gap. Within the range of 1.9 to 2.3 electron volts (eV), the band gaps were found to be present.

Nanocomposites materials of silver (Ag) with polyethene oxide, venal polyalcohol and polyvinyl pyrrolidone were synthesized by chemical reduction method using trisodium citrate (TSC) as a reduction agent. Silver based nanocomposites deposited as a film by dropcasting technique on (2x2 cm2) glass substrates. The effect of polymer matrix type on the optical properties (surface plasmon resonance, transmission and direct and indirect bandgap) were investigated. It was observed from the absorption spectra of the various synthesized materials that the type of polymer used in the preparation process significantly influences the location of the plasmonic absorption peak and the amount of the energy gap.