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Highlights Glass fiber reinforced plastics (GFRPs) is a key material for the outer protecting layer of ships as well as for energy storage tanks. Its ballistic and blast resistance is closely related to the inclusion structure of its glass fiber and polyester matrix, however, the related detailed studies have not been reported. In this paper, ballistic shooting tests and finite element simulations are both employed to investigate the ballistic limit velocities (V50) of GFRPs and reveal the effects of glass fiber layers and the polyester matrix thickness on the V50. The results show that the V50 of GFRPs is essentially linearly related to the thickness of the target plate for a given number of glass fiber layers. An increase in the number of glass fiber layers enhances the overall V50 value of GFRPs, but the linear relationship with the thickness remains unchanged. The target plate with more layers of glass fiber interacts with the projectile for a longer time, resulting in the debonding of the fiber and the resin matrix. The resin around the crater loses its support and then produces irregular cracks. Based on energy conservation, a theoretical model for predicting the V50 of GFRPs with considering the effects of glass fiber and polyester matrix is proposed. After comparing the results of theoretical calculations with experimental and simulation data, the relationship equations between the key parameters (ballistic strength) in the model and the number of fiber layers and target plate thickness are finally given. These findings can provide support for the design of ballistic GFRPs. Ballistic velocity limit (V50) of glass fiber reinforced plastics (GFRPs) obtained by experiment and finite element simulation Tuning the V50 of GFRPs by designing the number of glass fiber and polyester thickness. Proposed a theoretical model for predicting the V50 of GFRPs. [ABSTRACT FROM AUTHOR]

Allyl ether naphthol resin (ANPF) was synthesized by introducing 1,5‐dihydroxynaphthalene and 2,7‐dihydroxynaphthalene into phenolic resin and was copolymerized with 4,4′‐bismaleimidodiphenylmethane resin (BDM) to obtain allyl ether naphthol‐modified bismaleimide resins (15‐ANPF‐BDM and 27‐ANPF‐BDM). The resulting thermal stability and glass transition temperature (Tg) were explored by thermogravimetric and dynamic mechanical analyses. The char yield of 15‐ANPF‐BDM at a temperature of 800°C was 46.0%. Additionally, the Tg of 15‐ANPF‐BDM was measured as 311°C, which is an increase of 44°C compared to that of c. The mechanical properties of the ANPF‐BDM/quartz fiber (Qf) composites were also investigated. The results reveal that ANPF‐BDM/Qf composites exhibit similar mechanical strength to APF‐BDM/Qf composites at room temperature. In addition, the mechanical properties of the ANPF‐BDM/ Qf composites demonstrated significant improvement in mechanical properties retained significantly improved at 200°C, with a 68% flexural strength retention and a 96% interlaminar shear retention of 15‐ANPF‐BDM/Qf composites. Thus, ANPF‐BDM/Qf composites exhibit outstanding mechanical properties at 200°C. [ABSTRACT FROM AUTHOR]

Diglycidyl ether of bisphenol A (DGEBA), a key intermediate for epoxy resins, provides strong adhesion, processability and the resulting thermoset boasts high cross linking density. However, the inherent brittleness and susceptibility to cracking restrict its advanced applications. To overcome these drawbacks, CO2 fixed cyclic carbonate from castor oil (CCO) was synthesized from epoxidised castor oil (ECO) and used in varying quantities as a toughening agent for amine cured DGEBA. Different amines have been utilized to cure the epoxy and to study the structure–property relationship by fixing the amount of CCO. The inclusion of 10% CCO resulted in improvement in the tensile strength, storage modulus, flexural modulus, and impact strength of the epoxy‐urethane hybrid. Moreover, the epoxy‐urethane networks had reduced cross linking density imparted by the fatty acid units of CCO and the presence of unreacted carbonate groups facilitated molecular movement, thereby contributing to energy dissipation during the deformation process. Further incorporation of the CCO lowers the mechanical properties of the hybrids due to a reduction in cross linking density. Trimethylolpropane tris[poly(propyleneglycol)amine terminated] ether cured system exhibited the highest thermal stability compared to hexamethylene diamine, isophorone diamine, and 4,7,10‐trioxa‐1,13 tridecanediamine. The Tg decreased as the CCO content increased, while the water contact angle increased. [ABSTRACT FROM AUTHOR]

Highlights Glass fiber reinforced polymer (GFRP) composites can be subjected to different environmental conditions such as temperature, humidity, ultraviolet radiation, hydrothermal cycle, acidic and alkaline solution in environments where they operate. These environmental conditions cause different damage mechanisms in composites such as pore formation, micro‐cracks, delamination, fiber breakage, fiber/matrix interface separation, plasticization, swelling and surface color change. In this study, wear properties of hybrid glass fiber reinforced polymer composites exposed to various environmental conditions for constant load (60 N), speed (500 rpm) and 2 h were examined comprehensively, depending on material content and environmental conditions. In this experimental study, the service conditions in glass fiber reinforced composites were simulated using different artificial aging environments such as acidic environment, hydrothermal cycle and UV radiation. In addition to the material content, it appears that the environmental conditions to which composites are exposed has a significant effect on friction coefficient. Considering environmental conditions, it is seen that the acid environment and hydrothermal cycle have reduced wear resistance of GFRP composites, while UV radiation improved wear resistance of the composites. In C2 sample, the wear rates under different conditions are 1.87 × 10−14 m3/Nm in non‐treated sample, 6.05 × 10−14 m3/Nm in acid environment, 4.79 × 10−14 m3/Nm in hydrothermal cycle and 0.59 × 10−14 m3/Nm in UV radiation. Friction coefficient of glass fiber reinforced polyester (GFRP) is higher under aged condition compared to non‐treated. Glass fibers used in correct proportions can reduce friction coefficient in GFRP. GFRP exposed to environmental conditions has an important effect on wear. Acid environment and hydrothermal cycle has reduced wear resistance of GFRP. UV radiation improved wear resistance of GFRP composite. [ABSTRACT FROM AUTHOR]

Uniform, stable, one-step dyeing of textile fabrics made from a mixture of natural and synthetic fibers using traditional methods remains problematic to this day. As an alternative to traditional methods, a one-step method for dyeing mixed cotton and polyester fabrics with a new natural dye—a complex of collagen and C r 3 + and C u 2 + ions—was proposed for the first time. Dyeing of pre-prepared cotton, polyester, and cotton–polyester fabrics is carried out by dipping in an aqueous dye solution, squeezing, drying, and heat setting. The influence of the mass ratio of dye components, fixation temperature, and pH of the solution on the degree of dye fixation was determined. A degree of sorption of dyes (14–25%) from the solution onto the surface of fabrics was established, which after heat fixation decreases slightly (1–3%). During washing processes, the copper complex is almost completely washed out from polyester and blended fabrics and remains in small quantities (2.4–3.8%) on the surface of cotton fabrics. After water washing, the degree of fixation of the collagen–chrome complex in fabrics is as follows: in cotton—8–10%, in polyester—10–12%, and in cotton–polyester—8–9%. The color coordinates of cotton and cotton–polyester fabrics hardly change before and after washing, but for polyester fabric, the changes are significant. The mechanism of interaction of the complex dye with the fibers was studied using the Fourier transform infrared method, and the morphology and distribution of the dye on the surface of the samples using the SEM-EDS method. The dye binds to cellulose through ionic and coordination bonds, and to polyester through joint melting. Therefore, unlike pure polyester fabric, cotton and cotton–polyester fabrics demonstrated high color fastness to washing and light fastness. The use of production waste, the exclusion of synthetic dyes and harmful chemicals, and single-stage dyeing of the material reduce the environmental burden. [ABSTRACT FROM AUTHOR]

A series of aryl-diazinyl-cyanoacetamide (2a–l) were prepared by coupling the appropriate diazotized arylamines with dioxoisoindoline cyanaoacetamide (1). Also, the cyclization of azo derivatives (2f, 2h, and 2j) with chloroacetonitrile to yield the pyrazole derivatives (5f, 5h, and 5j) was studied. Moreover, compound 2d reacts with malononitrile to afford compound (6e). In a similar manner compound, 2d reacts with hydroxylamine to afford the sole product tetrazine derivative 8d. All the newly synthesized compounds were fully characterized by both analytical and spectral analyses. The geometries of the azo and hydrazo tautomeric forms were optimized at the B3LYP/6-311G level of theory. The dyeing performance of the synthesized dyes on polyester fibers has been assessed. Most of the dyes showed a good affinity to polyester fibers. No details regarding the synthesis and dyeing performance of such dyes are reported before in the literature. [ABSTRACT FROM AUTHOR]

Concerns are constantly growing about our dependance on plastics derived from fossil feedstock, leading to the development of bio-based alternatives. The bio-based polyester poly(ethylene furanoate) (PEF) has attracted increasing attention from the scientific community due to its potential to replace mass-produced poly(ethylene terephtalate) (PET), mainly used in the packaging, film and fibre sectors. PEF can be 100% bio-based since both its monomers can be produced from biological resources, and exhibits superior properties compared to PET, such as its mechanical and gas barrier properties. As PEF gets closer to being produced at a large scale and entering the plastic market, its end-of-life management should be carefully studied in order to mitigate its environmental footprint. This review focusses on the state-of-the art of the main scenarios related to polymers waste, including mechanical and chemical recycling, composting and incineration. [ABSTRACT FROM AUTHOR]

It is a vital route to develop new fiber products with various physical‐mechanical properties by which their aggregation structure can be changed via controlling the spinning process parameters. In this study, five groups fiber samples had been obtained by changing the spinneret drawing ratio, two stages drawing ratio and two stages heat‐setting rate. The aggregation structure of the poly(ethylene terephthalate) (PET) industrial fibers from different spinning process was analyzed by combination use of thermal analysis, two‐dimensional wide‐angle X‐ray diffraction (WAXD), small‐angle X‐ray scattering (SAXS), and Infrared Spectroscopy (IR) measurements. It was found that, increasing the spinneret drawing ratio and two stages drawing ratio promoted the orientation and crystallinity within a certain range. For the subsequent two stages heat‐setting process, the disorientation of the amorphous chain is simulated by reducing the relaxation rate and heat setting temperature. Finally, a concise three‐dimensional structure model was established to explain the relationship between aggregation structure and property. These results have important reference for the structure and property analysis of polyester industrial fiber. [ABSTRACT FROM AUTHOR]

To study the effect of the finishing process on the mechanical properties of polybutylene terephthalate/polyethylene terephthalate (PBT/PET) bicomponent polyester fiber, PBT/PET yarns were subjected to heat-moisture and dry-heat treatment at different temperatures and times. The tensile properties, elastic recovery, stress relaxation, and creep properties of the yarn were tested. The crystalline structure of PBT/PET fiber before and after heat treatment was studied by X-ray diffraction (XRD) to explain the change in yarn mechanical properties. The mechanical model of PBT/PET yarn was established, and the change in mechanical properties was investigated theoretically. The results show that the strength of PBT/PET yarn decreases by 10.77%, and the elongation increase by 34.81% after dry-hear treatment at 160°C for 25 min. The mechanical properties of the yarn are affected by the temperature and time of heat treatment. XRD analysis shows that the crystallinity of PBT/PET yarn decreases with the increase of heat treatment temperature and time, which may be the reason for the change in mechanical properties of PBT/PET yarn. In addition, the established model can fairly well explain the viscoelasticity of PBT/PET yarn. [ABSTRACT FROM AUTHOR]

Large amounts of plastic waste are daily generated, becoming a global issue that needs to be addressed. Thus, new recycling alternatives have been explored, such as the depolymerization of poly(ethylene terephthalate) waste (wPET). These reactions can lead to the formation of oligomers and monomers, which can then be employed in new synthetic processes. The aim of this work is to use the products of the chemical recycling of wPET on the synthesis of hydrogels and evaluate the capacity of these materials to adsorb dyes aiming a wastewater treatment. The depolymerizations were done through glycerolysis reactions catalyzed by zinc (II) acetate under microwave radiation. Afterwards, the obtained oil was crosslinked with citric acid (CA) under tin (II) chloride catalysis to obtain the hydrogels. The water uptake capacity of the hydrogels ranged from 310% to 1442%, depending on the CA content. When placed in an indigo carmine solution, the hydrogels showed high adsorption capacity, removing up to 97% of the dye. The kinetic study revealed a physicochemical mechanism for the removal process, corroborated by Temkin isotherms. These results indicate that the chemical recycling of PET via glycerolysis is a viable alternative for producing hydrogels, reducing plastic waste while creating new tools for wastewater treatment. [ABSTRACT FROM AUTHOR]

The roughness of woven fabric surface has so far been mainly investigated as a key characteristic of comfort in contact with the skin. The analysis of roughness can be extended to various contexts and applications, becoming an important tool for understanding how textile materials react in interaction with different finishing agents, as well as for gaining insight into the durability and effectiveness of treatments. This research presents a comprehensive study on the impact of alkaline hydrolysis and chitosan coating on the roughness of polyester woven fabric, utilizing both novel and adapted methods. The study employed contact and optical methods to analyze fabric and fiber surface characteristics, highlighting the significance of roughness profile parameters in understanding material changes post-treatment. The investigation revealed that mechanical action, alkaline medium, washing temperature, and detergent residues contribute to fabric erosion and modification during washing, with chitosan coatings creating pronounced surface irregularities. Comparative analysis showed significant fabric roughness changes post-washing, while fiber roughness changes were treatment specific. Despite initial increases in fiber roughness due to treatments, their durability decreased after washing. These findings emphasize the importance of roughness analysis in optimizing textile finishing processes and washing cycles, impacting both comfort and treatment efficacy. [ABSTRACT FROM AUTHOR]

In order to improve the basic pavement performance of high-elastic asphalt concrete filled in the expansion longitudinal joints of seamless bridges, rubber particles and polyester fibers were added to optimize the mix proportion of elastic asphalt concrete, and the optimal asphalt–aggregate ratio was determined. The influence of rubber particles and polyester fibers on the basic pavement performance of high-elastic asphalt concrete was studied. The results show that when the dosage of polyester fiber is not more than 0.6%, the optimal asphalt–aggregate ratio is 1:5, and when it exceeds 0.6%, the optimal asphalt–aggregate ratio is 1:4. The incorporation of rubber particles reduces the compressive strength of high-elastic asphalt concrete but enhances its high-temperature stability, fracture performance, and deformation recovery ability. The incorporation of polyester fibers improves its compressive strength, high-temperature stability, fracture performance, and deformation recovery ability. In addition, the incorporation of rubber granules and polyester fibers promotes the use of green building materials and provides strong support for sustainable building practices. [ABSTRACT FROM AUTHOR]

This work aims at investigating the effect of two eco‐friendly chemical treatments of Agave Americana fibers (AAFs) on morphology and mechanical properties of poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate) (PHBHHx) biocomposites prepared by melt compounding. Acid citric and sodium bicarbonate treatments are used separately to modify the fiber surface before their incorporation into PHBHHx matrix at 30 wt%. The study reveals through SEM observations that the fracture surface of untreated PHBHHx biocomposite shows a poor fiber‐matrix adhesion with the presence of many microvoids at interface and also some fibers pullout. However, less surface defects with a finer morphology are observed on the treated biocomposite samples resulting in improved tensile and flexural properties compared with neat polymer, being however, more pronounced for those modified with sodium bicarbonate. The study highlights the beneficial effect of the green treatments investigated to enhance the mechanical properties of PHBHHx biocomposites. [ABSTRACT FROM AUTHOR]

Novel research has been conducted to characterize fiberboards made from palm frond fibers and polyester resin. In this study, polyester resin served as the matrix, and palm frond fibers with a size of 80 mesh were employed as the filler. The fiberboard composites were produced using a hot press at 70°C for 20 minutes, with varying mass compositions of polyester resin to palm frond fibers: S1 (60%:40%), S2 (65%:35%), S3 (70%:30%), S4 (75%:25%), and S5 (80%:20%). Parameters observed include physical properties (density and porosity), mechanical properties (impact, tensile, and flexural strength), and microstructure analysis using scanning electron microscope (SEM) and differential scanning calorimetry (DSC). The results indicate that S5 exhibits optimal properties, including a density value of 1.197 g/mL, low porosity at 0.232%, and mechanical characteristics with an impact strength of 271.251 J/m2, tensile strength of 23.221 MPa, and flexural strength of 149.837 MPa. However, according to the DSC data, S1 stands out with a higher temperature water evaporating point at 82.48°C, indicating greater thermal stability. In addition, SEM results for the S5 sample reveal minimal voids, enhancing the fiberboard composites' physical and mechanical properties and demonstrating high stability. This fiberboard can be classified as a High-Density Fiberboard (HDF) according to JIS A 5905:2003. It is a viable alternative for household furniture, offering a substitute for traditional wood. [ABSTRACT FROM AUTHOR]

Application and production points of colored ultra short fiber in the development of air-jet vortex spinning fancy yarn were discussed. Slub device on the drawing frame was installed, colored ultra short viscose fiber, natural bamboo pulp fiber and coconut charcoal modified polyester fiber were used to spin long slubby segment colored yarn by air-jet vortex spinning technology. In view of the relatively short length of viscose fiber, the technology measures such as short flow, reducing the gauge and reducing the beater speed were used in the process. The results showed that the developed air-jet vortex spun segment colored yarn had the characteristics of long color segments and high production efficiency. The color points on the cloth surface were hazy, sometimes forming continuous distribution, sometimes dispersed-point distribution, which forming unique style different from the traditional segment colored yarn. [ABSTRACT FROM AUTHOR]

This study unveils a sustainable, easily recyclable biocomposite, leveraging the dynamic nature of covalently adaptive bonds in a vitrimer matrix. The fabrication involved a fatty acid-derived vitrimer as the polymer matrix and multi-layered, nonwoven flax mat as reinforcing scaffold. The incorporation of these fibers significantly improved the mechanical performance of the vitrimer matrix uniformly. The ester-based covalently adaptive network plays a crucial role in enabling exceptional fiber-matrix bonding, as well as recyclability. The vitrimer matrix dissolves in ethylene glycol through transesterification, facilitating complete material recovery and biocomposite recycling without compromising the original properties of the matrix and reinforcing fibers. [ABSTRACT FROM AUTHOR]

The self-made COPET/CaCO3 masterbatch and PET masterbatch were used to modify the traditional PET fiber through melt spinning. The process parameters for preparing COPET/CaCO3/PET porous fiber by alkali and acid treatment were optimized using single factor control variable method, and the fiber properties were tested and characterized. The results show that when the NaOH mass fraction is 4% and the HCL mass fraction is 3%, the fibers have good apparent morphology and pore structure. Under the optimal treatment conditions, the fiber contains uniformly distributed pores, and the pore size is concentrated between 15 nm and 54 nm. The fracture strength, linear density, specific surface area, and melting temperature of the fibers are 1.29 cN/dtex, 4.84 dtex, and 5.527 3 m²/g, respectively, and 253.85 °C, respectively. [ABSTRACT FROM AUTHOR]

In order to explore the changes in the performance of polyester fibers prepared by different processes under alkaline conditions, high tenacity (HT) polyester industrial fiber and fully drawn polyester yarn (FDY) of high speed spinning were selected for artificial accelerated aging tests in alkaline conditions at 85 °C. The mechanical properties of fibers were tested during the processes. Wide-angle X-ray diffraction, small-angle X-ray scattering and intrinsic viscosity were used to study the change in crystalline, lamellar structure and chemical structure of polyester fibers. The results showed that the changes in structure and properties of two polyester fibers in alkaline conditions can be divided into three stages. At the initial stage, the breaking strength and degree of orientation of the fibers first decreased significantly due to the effect of water and heat, while crystallinity remained constant. It was caused by the disorientation of amorphous orientated molecular chain segments in the frozen state, resulting in shrinkage. Then the decrease in breaking strength of fibers was slowed down, which was attributed to the breakage of amorphous molecular chains and the formation of a few new crystal structures. In the final stage of alkaline hydrolysis, the breaking strength of the fibers decreased significantly, while the crystallinity of fibers began to decline and the intrinsic viscosity reduced constantly, indicating that the breakage of amorphous molecular chain became the dominant factor. The alkaline hydrolysis reaction rate and the change degree of microstructure and mechanical property parameters of HT fibers were lower than those of FDY fibers, owing to the greater crystallinity and crystal size of HT fibers, which inhibited the erosion of water and OH-. As a result, HT fibers had a better alkaline hydrolysis resistance than FDY fibers. [ABSTRACT FROM AUTHOR]

This review concerns the application of disperse dyes to poly(ethylene terephthalate) fibres using aqueous immersion dyeing processes and the roles of both elevated dyeing temperatures and carriers in the disperse dye/polyester fibre and disperse dye/carrier/polyester fibre dyeing systems, respectively. In this part of the paper, a mechanistic model of the disperse dye adsorption process is presented that is based on the role of dye solubility in disperse dye‐PET fibre substantivity. It is shown that the dye solubility model of disperse dye adsorption, which can be articulated using a simple mathematical approach, is able to account for the reasons why elevated dyeing temperatures are utilised in HT dyeing processes, and also why dyeing accelerants enable dyeing to be achieved using lower temperatures of ~100°C. [ABSTRACT FROM AUTHOR]

According to recent studies, user comfort is one of the major challenges faced regarding the vehicle seating. The outer upholstery layer of the seat cover is the main factor contributing to overall user discomfort in the driving environment. This is related to the limitations of the conventional fabrics used. Therefore, alternative textile materials for seat covering are being increasingly sought out. In this work, we propose innovative shape memory-based seat covering fabrics offering improved comfort properties. Shape memory polyurethane (SMPU) multifilament yarns were combined with polyester (PES) yarns to produce three types of woven fabrics having the typical structures used in seat coverings (plain, twill 2/2 and derived twill) using a fixed warp and weft ratio of 3PES:1SMPU. The effects of SMPU yarns on the physical characteristics of the fabrics (thickness, areal weight, yarn density, and tightness) as well as on their mechanical behavior, shape memory effect, thermal comfort, and abrasion resistance under similar usage conditions in car seat covers were investigated. Improvement was observed in the ergonomic comfort with maintained thermal comfort in the presence of SMPU multifilament yarns, with this effect being more noticeable in the twill fabrics. The thermodynamic SMPU-based fabrics used in this study could be potential candidates for use in seat upholstery given the improvement in user comfort over extended use. [ABSTRACT FROM AUTHOR]

Textiles are one of the most frequently collected items at crime scenes. Even so, the mechanisms that create bloodstains on textiles are not well understood. This is likely due to the wide range of textiles and the many surface treatments given to them to enhance their performance. In this study, the final appearance of 50 μl passive drip stains on four in-house knitted apparel textiles (scoured cotton, hydrophobic cotton, hydrophilic polyester and hydrophobic polyester) was investigated. The yarns used to make the knits were 167 dTex polyester filament and 342 dTex cotton staple yarns. They were knitted on the same knitting machine under nominally identical conditions. The area of bloodstains on the scoured cotton knit fabrics was 46 mm2 and 30 mm2 on the hydrophobic cotton. i.e. the stains on the hydrophilic cotton were 50% larger than on the hydrophobic cotton. The bloodstains on hydrophobic polyester were only 15.6 mm2, but were 242 mm2 on hydrophilic polyester, i.e. 15 times larger. The stain areas on the polyester were both smaller (hydrophobic finish) and larger (hydrophilic finish) than on the cotton fabrics. It is shown that these typical chemical treatments play a much more important role on bloodstain areas than fibre type or fabric construction. [ABSTRACT FROM AUTHOR]

In the quest to elevate the mechanical properties of cellulose nanofiber-reinforced poly (lactic acid) composite materials for robust industrial applications, we conducted multiscale nonlinear finite element analysis rooted in homogenization theory. Our study delved into the intricate web of mechanical mechanisms and their pivotal influencers. This paper zeroed in on three paramount factors: the distribution of fibers, the fiber–matrix interface, and the aspect ratio of the fibers. For fiber distribution, we assumed fiber orientation control in fused filament fabrication and clarified the limit of material improvement by setting one-dimensional orientation as the upper limit. Our analysis of the fiber–matrix interface proposed a comprehensive three-scale structure, encompassing microstructures featuring intricate interfacial phases around the fibers, sub-microstructures with myriad dispersed fibers, and macrostructures subjected to external loads. The profound impact of the fiber–matrix interface on material properties was unveiled through a meticulous two-step homogenization process. Furthermore, we examined the substantial influence of the fiber aspect ratio on material properties. By unraveling the complex interplay among these critical factors, this research provided new design guidelines for fiber morphology to the performance of cellulose composites. [ABSTRACT FROM AUTHOR]

Recycled asphalt pavement (RAP) mixtures are widely adopted due to their significant economic and social benefits from utilizing pavement recycling materials. This study incorporates basalt fibers (BF) and polyester fibers (PF) into plant-mixed hot recycled asphalt mixtures to analyze their enhancement effects on the high-temperature, low-temperature, and fatigue performance at different RAP content levels. Additionally, the study investigates the impact of fiber and RAP additions on the compaction characteristics of the mixtures using gyratory compaction tests, aiming to increase the RAP content of plant-mixed hot recycled asphalt mixtures. Experimental results demonstrate that at 30% and 50% RAP content levels, basalt fibers exhibit more pronounced enhancement effects on the performance of recycled asphalt mixtures compared to polyester fibers. Incorporating basalt fibers increases the fracture energy of recycled asphalt mixtures by 8.63% and 13.9%, and improves fatigue life by 154% and 135%, respectively. Moreover, the addition of both types of fibers increases compaction difficulty, with polyester fibers showing a more significant influence on the compaction energy index (CEI). [ABSTRACT FROM AUTHOR]

The objective of this research was to examine the bamboo fiber preforming procedures and the effects of preforming on the mechanical properties. The bamboo fibers were bent to an angular shape by using mold compression. Different moisture contents were applied to the bamboo fibers before bending. Next, tensile tests were conducted on the preformed bent fibers to investigate the strength degradation caused by fiber damage during the forming process. Additionally, the vacuum preforming method, limited to a pressure of 1 atm, was used for bamboo fiber bending preforming. Different fillet radii of the angled shapes were used in the experiments to investigate the impact of the angle curvature at the bending points on the strength of the bent bamboo fibers. Unidirectional bamboo fiber mats were manually woven using polyester fiber lines and preformed with a closed mold. The fabrication of the unidirectional bamboo fiber/epoxy resin composites was conducted by vacuum-assisted resin transfer molding (VARTM). In this study, valuable insights into the design of the bamboo fiber preforming and composite manufacturing processes are provided, and our results can be used to contribute to the progress and utilization of the bamboo fibers in composite materials. [ABSTRACT FROM AUTHOR]

Polyurethane foams are widely used in daily life due to their superior performance. However, it is very challenging to recycle and reuse waste polyurethane foams since the three‐dimensional crosslinking network structure makes them non‐melting and insoluble. In this work, a low‐cost, green, room‐temperature solid‐state shear milling method is proposed to break the cross‐linking bonds of waste polyurethane foam (crosslinking density decreases from 0.768 to 0.489 mol dm−3). The recycled polyurethane (RPU) powders regain their thermoplastic processability. Recycled waste polyester (PET) fibers are modified through plasma treatment and used as reinforcing fillers for the reprocessed RPU elastomer. Compared to original PET fibers, modified polyester (m‐PET) fibers construct strong interfacial interactions and physical interlocks with RPU matrix, leading to significantly enhanced mechanical properties. Molecular dynamics studies demonstrate that RPU/m‐PET composites have higher cohesive energy density and lower free volume, and significantly improved compatibility, which greatly promotes stress dissipation upon stretching. This study provides a feasible strategy for the high‐value recycling of waste polymer materials. [ABSTRACT FROM AUTHOR]

The characterization of the flexural performances of short glass fiber reinforced polyether‐ether‐ketone (SGFR‐PEEK) composites fabricated by injection molding is a crucial and challenging task due to the process‐induced fiber orientation at different locations, resulting layered shell‐core‐shell microstructures and exhibiting large variations in mechanical performances. This article proposes a method for predicting the bending performance of SGFR‐PEEK and indicates the influence of fiber orientation on its bending behavior. This article reports a new scheme that combines multiscale homogenization with periodic microstructures and presents an experimental investigation of the flexural properties of SGFR‐PEEK composites. The distributions of fiber orientation through the thickness extracted from the micro‐computed tomography (μCT) were analyzed and reproduced with a layered skin‐shell‐core structure along the thickness at meso‐scale finite element model within representative volume elements (RVEs) of the macroscopic composites. Then, the effective properties of the RVEs were predicted using the homogenization method with the periodic boundary condition. The elastic modulus of skin‐shell‐core layers in the direction of flow are 4260.51, 4541.27, 4628.52, and 4630.84 MPa, respectively. The classical laminate theory (CLT) and the second homogenization implementation were then utilized in conjunction with the obtained mechanical properties of RVEs to predict the effective macrostructural behavior. The flexural modulus of the composite material was determined to be 5448.7 MPa through a three‐point bending test. The results obtained through lamination plate reinforcement theory and finite element simulation were 5887.4 and 5785.9 MPa, respectively, showing good agreement with the experimental findings. It is shown that the proposed multiscale scheme yields satisfactory agreement with experimental measurements. In addition, the effect of layered skin‐shell‐core microstructures on the flexural behavior was discussed. Highlights: RVEs of layered shell‐core‐shell microstructures were generated with specified fiber orientations.The homogenization scheme with the periodic boundary condition was adopted to accurately predict each layer mechanical properties.The proposed multiscale scheme was compared with experimental results and yielded satisfactory predictions.The effect of layered skin‐shell‐core microstructures on the flexural behavior was thoroughly studied by the multiscale analytical approach. [ABSTRACT FROM AUTHOR]

Fiber‐based products constitute a significant portion of plastic waste and cause environmental damage. In particular, discarded sanitary masks and fishing gear disintegrate into microfiber plastics, posing a significant threat to human health and ecosystems. In this study, we developed robust biodegradable nanocomposite fibers of poly(butylene adipate‐co‐terephthalate) (PBAT)/cellulose nanocrystals (CNCs) (1 and 2 wt%) through dry‐jet wet spinning, by using dimethyl sulfoxide (DMSO) as a common solvent. The control PBAT fibers exhibit remarkable mechanical performance with tensile strength and toughness of 160.0 MPa and 43.0 MJ m−3, respectively. CNC addition has a toughening effect with slightly reduced strength but enhanced toughness (148.8 MPa and 69.0 MJ m−3, respectively, for 2 wt% CNC); their mechanical performances are superior to those of previously reported PBAT‐based materials. The remarkable performance of the fibers is attributed to a highly oriented structure with a total draw ratio of 15 after post‐hot drawing. The control and nanocomposite fibers exhibit spot‐like patterns in 2D wide‐angle x‐ray diffraction patterns with Herman's orientation factor of 0.54–0.58. The theoretical Hansen solubility parameter confirmed the poor chemical affinity between the PBAT and CNC. Nonetheless, the rheological characterization revealed that well‐dispersed CNCs with DMSO produced a physical network in the PBAT matrix, resulting in the toughening effect. Such robust nanocomposite fibers consisting of fully biodegradable components are promising alternatives to nondegradable nylon and polyester fibers. Highlights: Robust biodegradable nanocomposite fibers of PBAT and CNC are prepared.Nanocomposite fibers are dry‐jet wet spun using DMSO as a common solvent.PBAT fibers exhibit strength and toughness of 160.0 MPa and 43.0 MJ m−3.2 wt% CNC toughens the PBAT fibers with an enhanced toughness of 69.0 MJ m−3.Rheological results confirm the toughening effect of well‐dispersed CNC in PBAT. [ABSTRACT FROM AUTHOR]

Highlights The work summarizes an innovative nanocomposite including synthesized copper nanoparticle (CuNP) impregnated wheat straw (WS) (the agronomic waste from an wheat plant) reinforced unsaturated polyester resin has been established. The addition of nanoparticles (NPs) increased the antifungal properties (~11%), durability (~9%), and strength (~39%) of the composites. Therefore, these nanoparticles have been synthesized from a copper chloride dihydrate precursor and they have been impregnated into wheat straw via cationization. This copper‐impregnated wheat straw (CuIWS) was formulated and employed to create a strong and long‐lasting nanocomposite with unsaturated polyester resin. Their morphological, mechanical, chemical, biodegradability (BD), and thermal properties were estimated and relationships were explicated systematically. Particularly, the tensile strength of polyester resin, crude and treated WS (cationized and copper‐impregnated) composites were 11.70, 14.20, 20.92, and 22.34 N/mm2 respectively. Therefore the reinforcement capability for crude, cationized and copper‐impregnated WS composites increased by ~22%, 75%, and 92% respectively. The residual ash was just about 16.23%, 12.04% and 6.56% for copper impregnated wheat straw composite (CuIWSC), Cationized wheat straw composite (CWSC) and untreated wheat straw composite (UTWSC) respectively point to the existence of ~4.1% Cu incorporated into the wheat straw which holds up the energy dispersive x‐ray (EDX) spectra of ~4.2% copper content. Thermogravimetric analysis (TGA) indicates that the nanocomposites are stable up to 325°C. These nanocomposites also show superlative crystallinity compared to other ones. Water uptake capacity followed typical Fickian diffusion law. The developed nanocomposites might be suitable for automobile and aircraft parts, furniture, and other indoor to outdoor applications. TS of the composites increased by increasing the WS filling up to 15%. The crystallinity increased after the addition of nanoparticles. The typical water uptake properties followed the Fickian diffusion rule. Incorporation of nanoparticles increased 11% antifungal properties. The developed nanocomposites are used for inside and outside applications. [ABSTRACT FROM AUTHOR]

The present work discusses the voltage difference as a measure for electrostatic charge generated from the contact‐separation and sliding of polymeric textiles on polyamide textile. It is proposed to blend polyester by carbon fiber to decrease the electrostatic charge generated on the contact surfaces. Because polyester acquires a negative charge and polyamide gains a positive one, carbon fiber is proposed to conduct the negative electrostatic charge from polyester to polyamide and conducts the positive one from polyamide to polyester, so that the resultant electrostatic charge decreased. The effect of carbon fiber to decrease the electrostatic charge depends on its area of contact, interaction, and distribution with polyester. Polyester double weaved by carbon fiber showed the lowest voltage. Based on those observations, it can be recommended to use double weaves of carbon fiber with polyester. The reduction in voltage was relatively lower for braided polyester by carbon fiber than that detected for double‐weaved polyester by carbon fiber. [ABSTRACT FROM AUTHOR]

The pervasive nature of plastic and the longevity of plastics leaves a legacy of microplastics (MPs) that contaminate our environment, including drinking water sources. Although MPs have been documented in every environmental setting, a paucity of research has focused on the transport and fate of MPs in groundwater. Previous field and laboratory studies have shown that MPs can migrate through aquifer material and are influenced by environmental factors. This study used controlled column experiments to investigate the influence of polymer type (polyamide, polyethylene, polypropylene, and polyester) and particle shape (fragment, fiber, and sphere) on MP retardation and retention. The results showed that all individual MP types investigated were retarded compared to the NaCl tracer, with a retardation factor ranging from 1.53 to 1.75. While hypothesized that presence of multiple types and shapes could change mobility, the results indicate that this hypothesis is not correct for the conditions tested. This study provides new insights into MP transport in groundwater systems based on the characteristics of MP particles. In addition, this study demonstrates the need for further research on types of MPs and under more conditions, especially in the presence of a mixture of types and shapes of MPs to gauge what is occurring in natural systems where many MPs are present together. Article impact statement: Microplastics are retarded approximately the same amount regardless of type or shape tested. [ABSTRACT FROM AUTHOR]

Humans produce different rates of sweating depending on the intensity level of a given activity. The clothing worn during the activity has a significant effect on the latent heat loss that can occur before, during, and after the activity. The water adsorption and spreading properties of a material yield differences in the amount of heat exchange that can occur between the person and the environment. Current test methods evaluate this using a value known as evaporative resistance, which is used to determine the heat exchange potential of a material. However, this value is only taken once the material has reached "steady state" and does not consider the sweating period before steady state is reached, or the drying period after steady state is reached. Therefore, an area under the curve (AUC) value was derived during these periods to compare the heat exchange properties of different materials. A sweating guarded hot plate was used to simulate different sweat rates, and therefore activity levels, to compare materials constructed of cotton, viscose, polyester, and wool. The overall latent heat loss of the hydrophobic wool was much less compared to the other samples with a gentler slope and lower AUC values than the other samples. It was found that the segment of time analyzed has a significant impact on the conclusion drawn about the latent heat loss of a material, p < 0.0001. Sweat rate also has a significant impact on the heat loss value, p < 0.0001, but is perhaps less useful when comparing samples to each other. It was found that comparing the different periods of the test could yield different conclusions when comparing materials for latent heat loss. Several current test methods do not consider phases outside of the steady state period and therefore miss valuable information pertinent to user comfort during these phases, especially in the post-exercise phase. [ABSTRACT FROM AUTHOR]

This research aims to identify the performance and mechanical characteristics of polypropylene-based antistatic bio-nano composites reinforced with 2% mono-diacylglycerols (MDAG) and 0, 0.5, 2.5% cellulose nanocrystals (CNC) and compared to pure PP. Based on the results of SEM on cross-section, there was an agglomeration of M-DAG and CNC on the PP matrix. XRD diffractogram pattern of antistatic bio-nano composites showed peaks representing the diffraction structure of glycerol monostearate and cellulose I. The FTIR spectrum of each formulation was very similar to the characteristic peaks of PP and showed three distinct peaks compared to pure PP. The melting temperature of antistatic composites without CNC (176.54 °C) was higher than pure PP (175.44 °C). Thermal stability of antistatic bio-nano composites with 0, 0.5, and 2.5% CNC were 472.07, 470.25, and 475.15 °C, respectively, higher than pure PP (468.27 °C). The best mechanical properties were 2.5% CNC with 11.071 MPa flexural modulus, 30.376 MPa tensile strength, 23.796% tensile elongation, 1.659 J/m2 impact strength, which were higher than pure PP, and it generated antistatic activity of 1010 - 1012 O/sq resistivity. [ABSTRACT FROM AUTHOR]

Purpose: The production of commodities from renewable organic material has gained enormous interest due to the rising public understanding of conscious development. Natural fibers are accessible in environment, and their parameters depend on their physical traits and chemically engineered makeup. Grewia optiva (GO) comes under the category of bast fibers, also known as Bhimal. This study aims to realize the consequences of alkali treatment on the characterization of natural fibers, their developed yarn and then the woven mat. Design/methodology/approach: Raw fiber was treated with 20% alkali solution. After treatment, it was evaluated for changes in the general laboratory system. This treatment is known as mercerization, through which the parameters of cellulose fibers can be enhanced. After this process, the content of cellulose increases due to the removal of the hydroxyl group. The removal of microfibrils, hemicellulose and the introduction of hydrogen bonds increase the interactive capacity of fiber. The job was divided into different sections, including acquiring fiber, developing yarn and creating a mat. Findings: The quality of the surface of the fiber was enhanced after the treatment. Its diameter was reduced to 54.72 microns. In the developed woven mat, it was densified using water treatment and attained grams per square meter (GSM) of 389.7. Originality/value: The usage of mercerization softens the fiber to twist into yarn, which is finally woven into a mat. Treatment of fabric or mat makes it denser to impart better strength. A woven mat of natural fibers provides maximum strength to the composites. [ABSTRACT FROM AUTHOR]

Poly(ester amide)s (PEAs) have received extensive attention due to their unique chemical structure and excellent properties. In this paper, a novel PEA (P6T6T) was prepared through melt polycondensation of terephthalic acid (PTA) and 6T6‐diamide‐diol (6T6), which was from the amidation of 6‐amino‐1‐hexanol and PTA. The structures were characterized by nuclear magnetic resonance, fourier transform infrared, and wide‐angle X‐Ray diffraction, and the thermal properties were evaluated by differential scanning calorimetry and thermal gravimetric analysis for P6T6T. It was found that the melting point of P6T6T was 217°C, which was about 37°C lower than that of PET (254°C), while the initial decomposition temperature was maintained at about 381°C. P6T6T had a fast crystallization rate (the half time of crystallization (t1/2) range from 35 to 60 s) and great crystallization properties. The saturated water absorption of the P6T6T was measured to be 2.53 wt%, which was three times that of PET (0.83 wt%). Furthermore, the water contact angle of P6T6T was determined to be 57.3°C, much lower than that of PET (94.7°C). All these results suggest that the incorporation of amide was an efficient method to improve the water absorption of polyester fibers. [ABSTRACT FROM AUTHOR]

Objective: The extraction process of alkali-extracted abalone viscera polysaccharides (Aavp) was optimized, and the preventive and repair effects of purified Aavp on H2O2 oxidative damage on L929 cells were studied to provide a reference for the development and application of Aavps. Methods: Crude Aavp was obtained by hot alkali extraction followed by alcohol precipitation, and its extraction process was optimized by the response surface method. The preventive and repair abilities of H2O2 oxidative damage on L929 cells were analyzed. Resulst: The optimum extraction conditions of crude Aavps were as follows: Solid-liquid ratio of 1:150 g/mL, extraction time of 2 h, and extraction temperature of 70 °C. Under these optimal conditions, the yield of crude Aavp was 8.57%. In the prevention test of H2O2 oxidative damage on L929 cells, different doses of purified Aavp (20, 50 and 100 μg/mL) had a significant preventive effect on L929 cell oxidative damage (P<0.001) but did not show a dose effect. The cell survival rate of the middle dose group (50 μg/mL) was the highest (71.94%±3.08%), which was slightly better than the positive control vitamin E group but not significant. In the repair test, different doses of purified Aavp (20, 50 and 100 μg/mL) had a significant repair effect on the oxidative damage of L929 cells (P<0.001) and showed a dose effect. In contrast, the cell survival rate of the high-dose group (100 μg/mL) was the highest (90.93%±1.17%), slightly higher than that of the positive control vitamin E group (87.96%±3.05%). The results showed that purified Aavp showed an excellent preventive and repair effect on H2O2 oxidative damage in L929 cells. Conclusion: Aavp has an ability to repair H2O2 oxidative damage of L929 cells. [ABSTRACT FROM AUTHOR]

Highlights The research on epoxy resin toughening is of great significance for its application in aerospace, automotive industries, marine vessels, and other fields. Poly‐ether‐ether‐ketone (PEEK) and carbon nanotubes (CNTs) are ideal candidates for epoxy reinforcement in thermoplastic materials and nanomaterials, respectively. In this study, CNTs were first chemically grafted onto PEEK microparticles using an amidation reaction. These modified hybrid materials were then utilized as fillers in epoxy composites to enhance their strength and toughness. The changes in sample structure, composition, thermal properties, and wettability during the chemical grafting process between CNTs and PEEK were systematically studied. In comparison to pure PEEK, the surface energy of CNTs‐PEEK hybrid materials increased by 11.58% due to CNTs grafting, resulting in improved wettability and enhanced interface bonding between PEEK and the epoxy matrix. Concurrently, the CNTs‐PEEK/epoxy composites exhibited significant enhancements, with the highest tensile strength, tensile elongation at break, flexural strength, and flexural modulus increased by 31.00%, 30.84%, 121.43%, and 23.22%, respectively. The positive reinforcement effect of modified CNTs‐PEEK fillers in epoxy composites and the exploration of CNTs grafting onto PEEK extend the potential applications of epoxy composites. CNTs were bonded to PEEK via an amidation reaction by the chemical grafting method. CNTs‐PEEK have an 11.58% increase in surface energy compared to pure PEEK. CNTs‐PEEK/epoxy composites showed improved mechanical properties. The enhancement mechanisms of CNTs‐PEEK/epoxy composites were analyzed. [ABSTRACT FROM AUTHOR]

The present investigation targets the physical, mechanical, and thermal characteristics of glass fabric‐reinforced vinyl ester/polyester hybrid laminates filled with ferrous, nickel, and tungsten micro‐particles. The metal‐fillers‐glass fabric reinforced vinyl ester/polyester hybrid composites was produced by distributing 1 wt% ferrous, nickel, and tungsten with an ultrasonication probe‐assisted wet layup method. Polyester resin reinforced with glass fabrics and tungsten fillers (PRGT) presents improved mechanical characteristics compared with other hybrid laminates, with tensile, compression, and flexural strength values of 157.89 MPa, 163.74 MPa, and 167.29 MPa, respectively. The fractographic microstructure of tensile fracture PRGT laminates exhibits that glass fibers pull out, microcracks, and lower gaps, because of stronger filler‐fabric‐matrix adhesion when compared with other hybrid laminates. The artificial neural network modeling was conducted to choose the best composite among the various manufactured composites. Statistical analysis was observed from the one‐way ANOVA technique, substantiating that the physical, mechanical, and thermal characteristics of metal fillers‐reinforced hybrid composites were statistically significant. Highlights: Metal‐fillers‐glass fabric reinforced vinyl ester/polyester hybrid composites.Selection of the best composite from developed composites by ANN.Tungsten fillers are a useful material for reinforcement. [ABSTRACT FROM AUTHOR]

Abdominal aortic aneurysm (AAA) is a common vascular disease that has attracted widespread attention due to its characteristic of being asymptomatic and high mortality rate. In this study, we present a novel woven vascular stent-graft, which can improve thrombus formation resulting from excessive smooth muscle cell proliferation following blood vessel stent implantation. To achieve this, we adopted the orthogonal design method to optimize the production process parameters and then coated the surface of the woven stent with chitosan/heparin using a layer-by-layer self-assembly technique based on the electrostatic binding principle, and the performance of the stent before and after modification was comprehensively evaluated. The results demonstrated that the coating had no impact on the mechanical properties, wall thickness, and cross-sectional water permeability of the membranes. Remarkably, the release rate of heparin reached as high as 90.88% at 216 h, effectively inhibiting the growth of smooth muscle cells. In conclusion, the new woven polyester vascular stent-graft provides a potential application prospect for the treatment of AAA. [ABSTRACT FROM AUTHOR]

This study presents an investigation into mechanical and thermal properties, as well as the microstructure of Automated Fiber Placement-manufactured laminates using a novel carbon fiber-reinforced low-melt polyaryl ether ketone polymer material. The material's lower melting temperature and lower melt viscosity as compared to established high-temperature thermoplastic materials as PEEK, promises favourable characteristics for the Automated Fiber Placement process. This work aims at in-situ consolidation and the influence of a heated tooling and a post process tempering step, which both turned out to be promising in previous investigations. Laminates were manufactured using a cold tooling, a heated tooling configuration, a cold tooling with a subsequent tempering process step and a hot-pressed reference laminate. Differential Scanning Calorimetry showed that crystallinity values more than doubled for the heated tooling and post process tempering configurations, compared to the cold tooling, reaching 24% and 30%, respectively. Mechanical strength values showed an increase in interlaminar shear strength and compression strength but did not increase to the same extent as was expected from the increase in crystallinity. With Scanning Electron Microscopy differences in the microscopic structure of the polymer matrix could be detected. While the post process tempering step leads to a mostly lamellar crystalline structure, the heated tooling configuration and the post process hot pressing induce a predominance of crystalline spherulites, which might positively affect the mechanical performance. Computed Tomography scans revealed a high amount of porosity in the in-situ-manufactured samples and unprocessed tape material, which likely mitigated the positive effect of increased crystallinity. [ABSTRACT FROM AUTHOR]

In this research, hollow inorganic microsphere (Q-cel) reinforced unsaturated polyester composite is produced, and its thermophysical properties have been characterized. The thermal decomposition kinetics of the composite obtained at different heating rates and various compositions are modeled using artificial neural networks. Also, the production optimization of the polyester composite has been evaluated using response surface methodology. The study has been repeated for certain heating rates (5, 10, and 20 K/min). Activation energies of polyester composites have been calculated using thermogravimetric data and kinetic methods. Changes in activation energy during the thermal decomposition (4 wt.% Q-cel, 94 wt.% UP, 580–660 K, and 20 K/min) of the composite are compared using FWO (129.4 kJ/mol), KAS (127.6 kJ/mol), and CR (126.5 kJ/mol). According to the results, it is seen that the activation energy goes up as the temperature and Q-cel ratio by the mass increase. When the amount of the filler in the polyester composite increases, the thermal conductivity coefficient also rises. As well as, it is determined that as Q-cel ratio in the mixture raises, the density of the composite decreases and Shore D hardness goes up. A new and original composite has been produced with Qcel-reinforced unsaturated polyester. The density of the composite is low, its thermal stability is high, and its easy processability will provide a great convenience. Modeling the Qcel ratio of the composite with RSM and the activation energy with ANN have been provided fast, efficient and optimum results. With the composite obtained, both lightweight and thermally stable polymer materials will be produced. [ABSTRACT FROM AUTHOR]

A nylon-like polyester tire cord, which combined the characteristics of nylon and polyester tire cords, was designed as the carcass reinforcement material used to meet the increasing demands of the tire industry for performance and impact on the environment. Tires' carcass construction plays a crucial role in affecting handling performance and ride comfort. Small changes in the carcass component can lead to significant improvements in the total tire/vehicle performance. This study evaluated the performance of nylon-like polyester and nylon 6 motorcycle tires. The results showed that the nylon-like polyester tire passed all indoor tests, and post-cure inflation (PCI) could be eliminated, resulting in energy and cost savings. The rolling resistance coefficient of the nylon-like polyester tire was reduced by 6.8% compared to that of the nylon 6 control tire, which could save fuel and have a positive impact on the environment. Nylon-like polyester tire cord extracted from the experimental tire possessed a higher modulus compared to that of nylon 6 tire cord, which could lead to better handling and ride comfort performance. Morphological pictures showed that both nylon-like polyester and nylon 6 cords extracted from tires had a good rubber coverage and comparable adhesion properties. [ABSTRACT FROM AUTHOR]

Cellular metabolic activity can be detected by tetrazolium-based colorimetric assays, which rely on dehydrogenase enzymes from living cells to reduce tetrazolium compounds into colored formazan products. Although these methods have been used in different fields of microbiology, their application to the detection of bacteria with plastic-degrading activity has not been well documented. Here, we report a microplate-adapted method for the detection of bacteria metabolically active on the commercial polyester polyurethane (PU) Impranil®DLN using the tetrazolium salt 2,3-bis [2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide (XTT). Bacterial cells that are active on PU reduce XTT to a water-soluble orange dye, which can be quantitatively measured using a microplate reader. We used the Pseudomonas putida KT2440 strain as a study model. Its metabolic activity on Impranil detected by our novel method was further verified by Fourier-transform infrared spectroscopy (FTIR) analyses. Measurements of the absorbance of reduced XTT at 470 nm in microplate wells were not affected by the colloidal properties of Impranil or cell density. In summary, we provide here an easy and high-throughput method for screening bacteria active on PU that can be adapted to other plastic substrates. [ABSTRACT FROM AUTHOR]

Researchers have recently altered their focus and have become more interested in natural fiber-reinforced polymer composites because they are more ecologically friendly and environmentally conscious than synthetic fiber-reinforced polymer composites. Among the best sources of natural fiber, Grewia ferruginea, sometimes known locally as Lenquata, is a source of natural fiber from other plant fibers. The goal of this study was to create polyester matrix composites reinforced with short Grewia ferruginea plant fibers measuring 10, 20, and 30 mm. The fibers were extracted using the traditional water-retting method and chemically treated with 5% NaOH. The findings indicated that the average tensile strength of a single fiber from Grewia ferruginea plants is 214 MPa, with a density of 1.11 g/cm3. Furthermore, the composite, which was created with a fiber length of 10 mm, fiber weight ratio of 25 %, and polyester matrix composite of 75 %, exhibited superior performance since it is stronger than any combination that was used to create the composite in this investigation, with 18.3 MPa tensile and 35.2 MPa flexural strength. [ABSTRACT FROM AUTHOR]

The effect of the ductile engineered cementitious composites (ECC) on the unreinforced masonry (URM) prisms and beams was investigated through the appropriate experiments. The objective of the study was to propose a cost-effective strengthening scheme using a low-cost ECC which was prepared using polyester fibers that possessed moderate tensile strength and ductility. The performance of masonry prisms and beams was investigated with different strengthening schemes. Test results showed that with the application of the ECC layer, the strength of masonry could be significantly improved under flexural loads, and the brittle collapse was mitigated. The ECC retrofitted masonry prism possessed a maximum increase in strength and stiffness of 74% and 50%, respectively. A numerical model was developed based on the basic mechanical properties and the interfacial properties of the individual elements (ECC, brick, and mortar). The numerical model was able to accurately predict the peak strengths and the failure modes of the masonry prisms and the beams. [ABSTRACT FROM AUTHOR]

The Sidr Leaves Powder (SLP) is full of natural renewable, and cost-free energy resources with excellent heat resistant properties. Mixing natural fillers in conjunction with unsaturated polyester increases the mechanical and thermal features of composites, which eliminates or reduces the need for additional binders. This study probes the outcomes of supplementing Sidr Leaves Powder at different filler concentrations on the mechanical properties (durability, compression, and impact) as well as thermal conductivity accompanied by FTIR spectroscopy characterization of unsaturated polyester composites. Samples were made using hand-lay molding procedures. The consequences reveal that the maximal impact resistance is (2.52kJ/m²), the highest hardness (72.4 N/mm²), and the highest compressive strength about (48.7 MPa). Moreover, the thermal conductivity's value drops to (0.101 W/m.℃). on 25% volumetric fraction. With FTIR spectra, the evidence of alteration in the chemical content and molecular structure of nanocomposites with varying filler content emerged, making the analysis of the composite material properties possible. These outcomes indicate the prospective usefulness of these composites in such fields as furniture manufacturing, especially in case of a couch due to their super properties. [ABSTRACT FROM AUTHOR]