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This research explores the scope of natural fibers for prosthetic socket application. A variety of conditions including maladies, accidents, and genetic disorders, necessitate the adoption of prosthetic organs. The human body undergoes significant physiological changes over time due to factors such as growth, weight fluctuations, and the periodic replacement and adjustment of appendages. In this study, biocomposite materials are fabricated using vacuum bag technology, with sisal fibers reinforced in vinyl ester at five different weight percentages: 0%, 5%, 10%, 15%, and 20%. Mechanical characteristics are determined through destructive testing, including flexural, tensile, impact strength, and hardness measurements according to ASTM standards. Scanning electron microscopy (SEM) analysis is employed to assess factrography and bonding properties. Results indicate that the biocomposite with 15% sisal reinforcement exhibited superior tensile and impact resistance compared to other compositions and matrices. However, at the expense of impact strength, the 20% sisal-reinforced vinyl ester increased hardness and flexural strength by 47% and 27%, respectively. This research aims to expand natural fibers and their utility in biomaterial applications, outlining points for elaboration and enhancement in this field, along with addressing associated challenges. [ABSTRACT FROM AUTHOR]

Highlights The performance of carbon fiber‐reinforced thermoplastic composites (CFRTP) has been restricted by the performance of the interface. In general, the interfacial properties of CFRTP are determined by both the surface properties of the carbon fiber (CF) reinforcement and the infiltration properties of the thermoplastic matrices, which possess high melt viscosity and seem difficult to sufficiently infiltrate the fiber reinforcement. As a result, the melt flow characteristics of different matrices significantly influence the interfacial melt penetration and mechanical properties of CFRTP. In this paper, in order to explore the influence of melt flow characteristics of various thermoplastic resins toward CFRTP interfacial behaviors, high‐polarity polyamide (PA) and low‐polarity polypropylene (PP) resins are selected as representative resin matrices among commonly used resin systems. Specifically, the polarity differences and interface‐forming mechanisms of CFRTP are first established. Following a systematical discourse on the latest research progress of interfacial modifications in PP/PA‐based CFRTP are described, centering on the effects of various modification methods on improving the interlaminar/interfacial strength, toughness, impact strength, and bending strength of the composites. In addition, this paper also classifies the interfacial mechanisms of CFRTP in terms of interface bonding, interface strengthening, and interface failure. Finally, the shortcomings and future research directions are pointed out to achieve effective interfacial construction and innovative modification of CFRTP. An introduction of resin polarity differences of CFRTP is established. An introduction of interface‐forming mechanisms of CFRTP is established. State‐of‐art characterization techniques of CFRPs interface are provided. Effect of melt flow property on the interfacial behavior of CFRTP was explored. The interfacial mechanisms are systematically analyzed. [ABSTRACT FROM AUTHOR]

Highlights This study is an attempt to develop high‐quality hybrid composites via functionalization (for homogeneous distribution) of the graphene nanoplatelets (FGNP) and then doping to carbon fiber reinforced especial aviation epoxy matrix (Araldite LY5052) via vacuum bagging molding (VBM). The utilized materials were characterized by UV–Vis spectroscopy, tensile, impact, hardness tests, and fracture mode analysis using a scanning electron microscope (SEM). The results revealed a 92% (502.5 MPa) and 85% (490 MPa) improvement in tensile strength values by doping the 1 and 1.5 wt% FGNPs, respectively. There was an improvement in impact strength with the addition of FGNP; a 28% (3.23 J/mm2) increase was achieved in the nanocomposite with 1 wt% FGNP added, and there was a decrease again in the nanocomposite with 1.5 wt% FGNP added. However, it was still 12% (2.83 J/mm2) better than the neat composite. In addition, the results of examining the fractured surface structures of the impact and tensile test specimens were compatible with these results. It reveals a significant separation of fiber‐matrix bonds with 1.5 wt% FGNP contribution. While tensile and impact strengths peak at 1 wt% FGNP value and decrease afterward, hardness values increase in parallel with the increase in FGNPs. Composites were developed by functionalized graphene nanoplatelets (FGNP). The fiber‐matrix interface was strengthened with FGNP interphase. A 92% tensile strength increase was achieved with 1 wt% FGNP additives. 28% in impact strength and 55% in hardness increase by 1 wt% FGNP. The morphology confirmed that the FGNP interphase filled the interface. [ABSTRACT FROM AUTHOR]

This paper presents the obtaining and characterization of blends based on high-density polyethylene (HDPE) and plasticized starch. In addition to plasticized starch (28.8% w/w), the compositions made also contained other ingredients, such as polyethylene-graft-maleic anhydride as a compatibilizer, ethylene propylene terpolymer elastomer, cross-linking agents, and nanoclay. Plasticized starch contains 68.6% w/w potato starch, 29.4% w/w glycerin, and 2% w/w anhydrous citric acid. Blends based on HDPE and plasticized starch were made in a Brabender Plasti-Corder internal mixer at 160 °C, and plates for testing were obtained using the compression method. Thermal analyses indicate an increase in the crystallization degree of the HDPE after the addition of plasticized starch. SEM micrographs indicate that blends are compatibilized, with the plasticized starch being well dispersed as droplets in the HDPE matrix. Samples show high hardness values (62–65° ShD), good tensile strength values (14.88–17.02 N/mm2), and Charpy impact strength values (1.08–2.27 kJ/m2 on notched samples, and 7.96–20.29 kJ/m2 on unnotched samples). After 72 h of water immersion at room temperature, mixtures containing a compatibilizer had a mass variation below 1% and water absorption values below 1.7%. Upon increasing the water immersion temperature to 80 °C, the sample without the compatibilizer showed a mass reduction of −2.23%, indicating the dissolution of the plasticized starch in the water. The samples containing the compatibilizer had a mass variation of max 8.33% and a water absorption of max 5.02%. After toluene immersion for 72 h at room temperature, mass variation was below 8%. [ABSTRACT FROM AUTHOR]

In this study, we compare synergistic performance of two different nanofillers, namely halloysite nanotubes (HNT) clay and multiwalled carbon nanotubes (MWCNT), in conjunction with a fixed concentration (0.125 phr) of semi‐anthracite coal‐derived graphene oxide (AC‐GO) on mechanical properties improvement of EGFPs (E‐glass fiber‐based epoxy resin composites). The dispersion of AC‐GO with HNT clay (GO‐H) and AC‐GO with MWCNT (GO‐C) within epoxy matrix was achieved using sonication and homogenization. Further mixture was incorporated into mats of E‐glass fiber employing "vacuum‐assisted resin infusion molding" (VARIM). Significant enhancements (18.3% flexural strength, 14.6% tensile strength, and a slight increase of impact strength (1.8%)) were observed in EGFPs reinforced with GO‐H at 0.50 phr loading of HNT, with an AC‐GO concentration maintained at 0.125 phr. Correspondingly, optimal values for GO‐C reinforced EGFPs at 0.25 phr were 40.3%, 18.7%, and a 10.5% decrease in impact strength, respectively. Analytical techniques such as XRD, FESEM, EDX mapping, and FTIR reveal presence of relatively abundant functionalities and strong interfacial adhesion in GO‐H as well as GO‐C. The cost of HNT clay is approximately 15 times cheaper than industrial‐grade MWCNTs, therefore, these results underscore potential of GO‐H as a very economical nano‐reinforcement alternative to GO‐C for polymer nanocomposites. Highlights: 0.50 phr HAGRP improves 18.3% flexural, 14.6% tensile, 1.8% impact strengths.Beyond 0.50 phr HAGRP and 0.25 phr CAGRP, mechanical properties decreased.0.25 phr CAGRP improves 40.3% flexural, and18.7% tensile strengths.FESEM, FTIR reveal strong interfacial adhesion between nanofillers and epoxy.GO‐H has proven to be an inexpensive reinforcement for polymer nanocomposites. [ABSTRACT FROM AUTHOR]

In this work, a series of functionalized MWNTs/EP composites were fabricated by epoxy resins (EP) and functionalized multi-walled carbon nanotubes (MWNTs). The dispersion of MWNTs in the EP matrix, through different methods, i.e., stirring, solvent, and emulsion dispersion, was investigated. Results show that the homogeneous dispersion of the MWNTs/EP composites was achieved, and the glass transition temperature (Tg) increased to 119℃. The tensile strength and modulus of elasticity were 1.690 GPa and 62.5 MPa, respectively, and the impact strength reached 4.97 KJ/m2 for the MWNTs/EP, with a 6 wt% MWNT loading. In addition, the resistivity of the MWNTs/EP composites decreased from 1013 to 106 Ω·cm in the initial EP matrix. The incorporation of MWNTs and a novel dispersion method effectively modified the mechanical and electrical properties of the initial EP matrix, and improved the inherent structural defects of the initial EP matrix, reducing the brittleness and impact resistance. With further research, this composite material has the potential to further broaden the application field of novel materials based on the EP matrix. [ABSTRACT FROM AUTHOR]

Epoxy systems are widely used in high-performance applications due to their strong strength and high modulus of elasticity. However, their use in structural applications is limited by their low toughness and brittleness. This study aims to enhance the toughness of fragile epoxy resin by incorporating natural rubber (NR) and commercial plastics (PMMA and ABS). Two groups of polymeric blends were formulated: Epoxy/NR/ABS/PMMA. Ternary blends were prepared with varying weight percentages of NR and ABS, and the blend with 1% NR and 3% ABS showed the best tensile properties. Quaternary blends were then created by adding different percentages of PMMA to this ternary blend. The blend containing epoxy with 1% NR, 3% ABS, and 9% PMMA exhibited significant improvements in mechanical properties, including impact strength, flexural strength, fracture toughness, and tensile strength. Compared to neat epoxy and the ternary blend (1% NR: 3% ABS), the quaternary blend showed increases in flexural strength (42.7% and 23.1%, respectively) and flexural modulus (93.6% and 41.6%, respectively). The impact strength and fracture toughness of the quaternary blend improved by 82.2% and 115% over neat epoxy and by 47.2% and 44.46% over the ternary blend, respectively. [ABSTRACT FROM AUTHOR]

In this study, acrylonitrile-butadiene-styrene (ABS) was used as the matrix, and polybutylene succinate (PBS), bagasse fiber (BF), and nano-CaCO3 were used as fillers to prepare high-performance and biodegradable ABS/PBS/BF/nano-CaCO3 composites by melt blending, to explore the effects of the addition of PBS, BF, and nano-CaCO3 on the mechanical properties and thermal stability of the composites, and the ABS/PBS/BF/nano-CaCO3 composites were tested and characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric (TG), X-ray diffraction (XRD) and scanning electron microscope (SEM). The results showed that the addition of PBS, nano-CaCO3 and modified BF could improve the fiber-matrix crystallinity, compatibility and thermal stability. The best performance of the composites was achieved when the mass fraction of PBS was 5%, the mass fraction of BF was 5%, the mass fraction of nano-CaCO3 was 5%, and the tensile strength and impact strength of the materials were 52.74 MPa and 8.416 5 kJ/m², respectively. The study could provide a good basis for the biodegradable automotive composites preparation. [ABSTRACT FROM AUTHOR]

This study investigates the effects of incorporating glass microspheres (GMSs) as fillers in carbon fabric–epoxy composites (CFECs) on their degradation behavior under environmental conditions such as moisture and ultraviolet rays. The GMS-filled composites were subjected to accelerated ageing and evaluated using dynamic mechanical analysis (DMA), the Charpy impact test, and inter-laminar shear strength (ILSS) tests. The results indicate that the addition of GMS fillers significantly improves the stiffness and viscoelastic behavior of the composites. However, the impact strength of the composites decreases with the addition of GMS fillers and accelerated ageing. The ILSS results demonstrate that the addition of GMS fillers improved the interfacial bonding between the carbon–epoxy matrix and fillers. This study provides insights into the mechanical properties of GMS-filled carbon–epoxy composites. [ABSTRACT FROM AUTHOR]

The primary objective of the present study was to transform discarded agricultural remnants and poultry waste into value-added materials. Rice straw and chicken feathers are disposed of after their primary consumption into landfills or are incinerated, causing pollution and environmental threats. In this study, epoxy composites were fabricated using different volume proportions (5–45%) of these raw and alkali-treated remnants, and their mechanical strength was tested. The flexural strength of the rice straw composites and chicken feather composites initially decreased with the addition of fibers from 5 to 35 vol% and then the values increased when the fiber content was more than 35 vol%. The chicken feather composites showed increased impact strength with fiber addition. Alkali treatment of the rice straw resulted in improved flexural and impact strengths of the composites due to the removal of the waxy layer on the fiber surface, which was observed in the FTIR studies. Alkali treatment of the chicken feathers did not produce any significant change in the flexural strength of the composites, but their impact strength increased with fiber addition. Hybrid composites fabricated using rice straw and chicken feathers exhibited enhanced flexural and impact strength properties both with and without the alkali treatment, corroborating the synergistic effect of these fibers. SEM analysis of the fractured samples showed noteworthy interfacial adhesion between the fibers and matrix. This study presents a better method for converting these disposable materials into value-added usable materials and increasing their life cycle in the circular economy. [ABSTRACT FROM AUTHOR]

AbstractA non-traditional friction stir welding (FSW) is used to joint the materials that are challenging to join together by utilizing the fusion welding processes. This study investigated the influence of the welding speed ratio (υ) to rotating speed (ꞷ) on the weld quality and found the relationship between mechanical qualities and welding peak temperature. With increase in (ꞷ/υ), there was a corresponding rise in peak temperature, leading to the expansion of both the nugget zone (NZ) and the softened region within the joint. As (ꞷ/υ) increased because of the increased heat, as a result in the joint hardness decreased. The joint ultimate tensile strength (UTS) increased with increasing (ꞷ/υ), then decreased, with the maximum value reaching 84.75% of the base material at a (ꞷ/υ) of 9.6. As a result of the low (ꞷ/υ), a flexural crack formed. In comparison to the base material, the thermos mechanically affected zone (TMAZ) and the nugget zone (NZ) showed greater impact strength. The impact strengths first increased and subsequently dropped with an increase in (ꞷ/υ). The tensile specimens’ fracture surfaces showed dimples, signifying a ductile mode of fracture. [ABSTRACT FROM AUTHOR]

This study fabricates multiscale glass fiber/epoxy composites by incorporating graphene nanoparticles (GNPs) and zinc oxide nanoparticles (ZnO NPs) to investigate the influences of NPs on the mechanical properties of composites. The composites are manufactured using the compression molding technique with different GNP contents (i.e., 0, 0.5, 1, and 1.5 wt.%), whereas the contents of glass fibers and ZnO NPs remained the same at 40 and 4 wt.%, respectively. Their mechanical properties, chemical compositions, and fracture morphologies are then evaluated. It is found that the mechanical properties of composites improve significantly at a lower content (i.e., 0.5 wt.%) of GNPs and tend to decrease at higher contents (i.e., 1 and 1.5 wt.%). The composite is composed of 0.5 wt.% GNPs exhibit maximum tensile modulus and strength of 6.74 GPa and 230.25 MPa, and flexural modulus and strength of 16.43 GPa and 831.79 MPa, respectively, impact strength of 47.25 kJ m−2, and maximum hardness (97.96 Shore D), among all nanocomposites. Moreover, fracture morphologies reveal that composite failure is predominately caused by fiber breakage, fiber‐matrix debonding, voids, and GNP agglomeration. The outcomes of this study provide some insights to promote the application of manufactured multiscale composites in the aerospace, automotive, and marine industries. [ABSTRACT FROM AUTHOR]

In this study, onium‐ion‐added nanoclay (NC)/microcellular polypropylene (PP) composites were created using a conventional injection molding machine. A chemical foaming agent was utilized to facilitate mixing. The primary focus was to analyze how altering the NC content affects the mechanical characteristics and the properties of the endothermic chemical foaming agent added PP/NC composites. The composites were created using a chemical foaming agent at a weight ratio of 1 wt% and NC at weight ratios of 0 wt%, 2.5 wt% and 5 wt%. The findings indicated that an increase in the NC ratio led to higher cell count and cell density, along with a reduction in cell diameter. Additionally, the outcomes demonstrated that the foaming of PP/NC composites resulted in decreased modulus of elasticity and tensile strength while enhancing impact strength. © 2024 The Authors. Polymer International published by John Wiley & Sons Ltd on behalf of Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Glass fiber/polymer composites are widely utilized in many structural applications because of their high specific strength and stiffness-to-weight ratios. In this study, woven glass fiber/epoxy was hybridized with short glass fibers of different lengths (2, 4, 6, 2+4, 2+6, and 4+6 mm) and contents (3, 6, 9, and 12 wt%) to produce hybrid woven SGF/epoxy composites. Variations in the thickness, fiber volume fraction, density, and void content of the prepared composites were determined. Mechanical tests such as tensile and Charpy impact tests were conducted. Compared to the woven fabric composites without short glass fibers (control samples), the tensile strength increased by approximately 13% at an optimum weight fraction of 3 wt% using short glass fiber lengths of 4 mm. Meanwhile, the incorporation of short glass fibers into the woven glass composites decreased the tensile modulus for all lengths. The maximum enhancement in the impact strength (approximately 14%) was achieved by the hybrid composite samples reinforced with 4 mm of short glass fibers at 3 wt%. This hybrid composite offers 18% and 20% improvements in the specific tensile and impact strengths, respectively. In summary, filling the woven fabric composites with specified short fiber contents and lengths can increase their mechanical performance when resin-rich regions are reinforced with short fibers without forming relatively thick interleaves between the woven fabric plies. [ABSTRACT FROM AUTHOR]

Polypropylene is a useful and widely consumed thermoplastic with very good properties that can be mixed with a combination of rubber and nanoparticles in order to eliminate its shortcomings. In this paper, the simultaneous combination of both the toughening effect of styrene–butadiene rubber (SBR) and the reinforcing effect of silicon carbide (SiC) nanoparticles were investigated in polypropylene matrix. Mechanical properties (tensile and impact strength [TS and IS]) of compounds were analyzed using the central composite design approach in Design‐Expert software. With two factors for input variables of SBR and SiC weight percentages, and their five levels (5, 10, 15, 20, and 25) and (0, 1.5, 3, 4.5, and 6), respectively, the central composite design approach employs 11 experiments for creation of models and the analysis of variance investigations with two output responses of TS and IS. Statistical results revealed that SBR and SiC contents had a significant effect on TS, IS, and the microstructure of compounds, as confirmed by scanning electron microscopy and energy‐dispersive spectroscopy images. To maximize all mechanical properties simultaneously with desirability functions, TS and IS of the optimum sample were computed to be 21.98 MPa and 8.66 kJ/m2 in amounts of 13.45 and 2.80 weight percentage (wt%) of SBR and SiC, respectively. Highlights: By increasing silicon carbide (SiC) in polypropylene/styrene–butadiene rubber (SBR), tensile strength decreases after a peak due to agglomeration effect.By increasing SiC in polypropylene/SBR, impact strength decreases after a peak due to agglomeration effect.By increasing SiC, the rubber particles' dimensions decrease according to scanning electron microscopy analysis.Simultaneous maximum of tensile strength and impact strength are 21.98 MPa and 8.66 KJ/m2, respectively.Optimum value of SBR and SiC in above maximums are 13.45 and 2.8 wt%, respectively. [ABSTRACT FROM AUTHOR]

Highlights Additive manufacturing has enhanced the production of complex parts with greater efficiency. However, inherent drawbacks such as reduced mechanical properties still pose challenges, necessitating further improvements to bridge the gap and meet industry demands. Therefore, this study investigated the use of glass fiber woven fabric with vat‐photopolymerization printing to achieve composite parts with superior mechanical properties. This approach offered an advantage in reducing the production time required for fiber‐reinforced composites by eliminating the need for curing processes or vacuum infusion. The mechanical properties of the composite panels manufactured with this method were investigated using flexural, interlaminar shear (ILSS), impact tests with different fiber orientations, and fiber volume fractions. The results of the mechanical tests showed maximum flexural strength of 295 MPa, impact strength of 174 kJ/m2, and ILSS of 20.58 MPa. In addition, optical images were taken to examine the cross‐section of the printed parts, which revealed a uniform and good wetting of the fibers. The findings suggest that glass fiber woven fabric in vat printing is a promising approach for producing composite parts with enhanced mechanical properties and reduced production rate. Additive manufacturing of glass fiber woven fabric reinforced with VPP printing. Reduced production time and microstructure by using layer‐by‐layer manufacturing. Maximum flexural strength: 295 MPa, impact strength: 174 kJ/m2, ILSS: 20.58 MPa. Consistent porosity values with the increasing number of layers. Promising for producing standard and thick composites with improved properties. [ABSTRACT FROM AUTHOR]

Highlights Interfacial adhesion properties are a key factor affecting the mechanical properties of composites. It is a very effective way to improve the low‐velocity impact resistance of composites by improving the interfacial adhesion properties. To improve the fiber/matrix interfacial adhesion properties of GF/PA6 (glass‐fiber/polyamide 6) composites, polyethyleneimine (PEI) and γ‐aminopropyltriethoxysilane (KH550) were used to co‐modify GF together in this study. The GF/PA6 composites with different modifications of glass‐fiber (GF) were also prepared using a hot pressing process, and then their flexural strength, shear strength, pendulum impact strength, and low‐speed impact resistance were investigated. Next, the relationship between fiber/matrix interfacial adhesion and mechanical properties of GF/PA6 composites was investigated by combining x‐ray photoelectron spectroscopy, scanning electron microscopy, and x‐ray computed tomography test results. The results showed that the GF‐reinforced PA6 matrix composite with co‐modified GF by PEI and KH550 (PEI‐KH550‐GF/PA6) had the best mechanical properties, with flexural, shear, and pendulum impact strengths of 660.7 MPa, 53.1 MPa, and 261.6 kJ/m2, respectively. Furthermore, the low‐velocity impact resistance was measured in terms of stress peak, absorbed energy, residual stress, and damage extension, and the results showed that the low‐speed impact resistance of PEI‐KH550‐GF/PA6 composites was also substantially improved that the Fmax increased from 7402.1 to 10414.0 N. Due to the poor surface activity of GF, in this experiment, GF was co‐modified with PEI and KH550 to achieve better fiber/matrix interfacial adhesion and successfully improve the mechanical properties of the composites; Different modification methods are used to improve the interfacial adhesion of the fiber/matrix interface. The relationship between the interface and impact strength of composites has been studied; The relationship between fiber/matrix interfacial adhesion and internal cracking in composites was investigated using X‐CT and SEM and other test results. [ABSTRACT FROM AUTHOR]

Highlights Highly transparent and mechanically robust thermoplastic composites have been developed by hot‐pressing PETG with E‐glass fabrics. The tow‐spreading technique facilitates the reduction of internal defects and fiber crimp angle in the composites, thereby significantly improving their optical and mechanical properties. The optimized composite containing 55.1 vol% glass fibers and 0.4 mm thickness has a high transmittance of 86.1%@616 nm and a low overall haze of 7.2%. Moreover, the 1 mm thick composites exhibit tensile strength of up to 340 MPa and impact strength of up to 86.3 kJ/m2. After 28 days of hygrothermal or UV aging, the composites show minimal changes in their glass transition temperature and thermal degradation temperature. The chemical structure also remains unchanged, with no observed crystallization. In comparison to UV aging, the composites demonstrate better resistance against hygrothermal aging. Specifically, the hygrothermal aged sample displayed a light transmittance retention rate of 93.5% and a bending strength retention rate of 94.3%, while these values were reduced to 73.3% and 90.5%, respectively, in the UV aged sample. The opto‐mechanical properties enhanced mechanism and aging degradation mechanism have been identified by microscopic morphological observation. This work provides an innovative and straightforward approach to fabricate transparent, recyclable, high‐strength thermoplastic composites. Highly transparent, mechanically robust, recyclable glass‐fabric reinforced thermoplastic composites are fabricated. Composites with spread‐tow fabrics exhibits improved transparency. The fabrication route is scalable and cost‐effective. The mechanism for opto‐mechanical properties enhancement are proposed. [ABSTRACT FROM AUTHOR]

Highlights Polylactide (PLA) biocomposite filaments containing hemp hurd (HH) of variable particle size were evaluated in comparison with injection‐molded counterparts using single/twin screw extrusion in this study. HH particle size (35, 50, and 160 μm) was parametrically investigated for its efficacy within PLA/HH biocomposites and fused filament fabrication (FFF)‐printed parts by assessing its effect on performance through rheological, microstructural, mechanical, and surface finish analyses. In addition, melt flow indexing, rheometry, scanning electron microscopy, mechanical testing, and x‐ray computed tomography were utilized to analyze microstructure, mechanical performance, and surface roughness. With an increase in particle size of the HH, the corresponding biocomposites showed increased flowability, and the injection‐molded specimens showed increased impact strength. The FFF printing of the biocomposite filament presented no challenges, and the mechanical properties of FFF parts enhanced with a particle size smaller than the printed layer thickness. Compared with injection‐molded parts, FFF‐printed samples showed higher impact strength. The FFF‐printed PLA/HH biocomposite samples showed considerable potential over their injection molded alternatives for low‐volume specialized applications. Polylactide (PLA)/hemp hurd (HH) biocomposite filaments with different particle sizes of HH were developed. Melt flow and impact strength increased when HH particle size increased. 3D‐printed part porosity and roughness increased when HH particle size increased. Higher HH particle size enhanced the mechanical performance of 3D‐printed parts. 3D‐printed parts exhibited higher impact strength than injection molded parts [ABSTRACT FROM AUTHOR]

In the present work, short glass fiber is superficially modified with different concentrations of polyhedral oligomeric silsesquioxanes (Trisilanol–Isobutyl, TSI-POSS) for processing as a filler in a polypropylene matrix (PP). It is observed that increasing the amount of TSI-POSS increases the fracture point and tensile strength; the opposite is the case for the strength impact property. The behaviors of both dynamic mechanical and thermal analyses are also observed. The flame behavior, i.e., the burning rate, decreases with increasing TSI-POSS in the polymers. [ABSTRACT FROM AUTHOR]

Cellulose nanopaper is a material structure that possesses high mechanical performance and is widely regarded as a promising 2D reinforcement for polymer matrix composites. This work explores the use of low grammage bacterial cellulose (BC) nanopaper as reinforcement for poly(acrylated urethane) interlayer adhesive to increase the impact performance of multilayer acrylic composites. The BC nanopaper is impregnated with an acrylated urethane resin and laminated between acrylic sheets to create BC/acrylic composites consisting of one, three, and five layers of BC nanopaper‐reinforced poly(acrylated urethane) interlayer adhesive(s). Both the poly(acrylated urethane)‐filled BC nanopaper interlayer adhesive and the resulting laminated acrylic composites are optically transparent. The incorporation of BC nanopaper into the poly(acrylated urethane) interlayer adhesive improves the tensile modulus by eightfold and the single‐edge notched fracture toughness by 60% compared to neat poly(acrylated urethane). It is also found that using poly(acrylated urethane)‐filled BC nanopaper interlayer adhesive proves beneficial to the impact properties of the resulting laminated acrylic composites. In Charpy impact testing, the impact strength of the multilayer acrylic composites increases by up to 130% compared to the "gold‐standard" impact‐modified monolithic acrylic, with a BC loading of only 1.6 wt%. [ABSTRACT FROM AUTHOR]

This review is a fundamental tool for researchers and engineers involved in the design and optimization of fiber-reinforced composite materials. The aim is to provide a comprehensive analysis of the mechanical performance of composites with epoxy matrices reinforced with carbon nanofibers (CNFs). The review includes studies investigating the static mechanical response through three-point bending (3PB) tests, tensile tests, and viscoelastic behavior tests. In addition, the properties of the composites' resistance to interlaminar shear strength (ILSS), mode I and mode II interlaminar fracture toughness (ILFT), and low-velocity impact (LVI) are analyzed. The incorporation of small amounts of CNFs, mostly between 0.25 and 1% by weight was shown to have a notable impact on the static and viscoelastic properties of the composites, leading to greater resistance to time-dependent deformation and better resistance to creep. ILSS and ILFT modes I and II of fiber-reinforced composites are critical parameters in assessing structural integrity through interfacial bonding and were positively affected by the introduction of CNFs. The response of composites to LVI demonstrates the potential of CNFs to increase impact strength by reducing the energy absorbed and the size of the damage introduced. Epoxy matrices reinforced with CNFs showed an average increase in stiffness of 15% and 20% for bending and tensile, respectively. The laminates, on the other hand, showed an increase in bending stiffness of 20% and 15% for tensile and modulus, respectively. In the case of ILSS and ILFT modes I and II, the addition of CNFs promoted average increases in the order of 50%, 100%, and 50%, respectively. [ABSTRACT FROM AUTHOR]

In this work, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) was modified by cellulose derivatives, and the effects of different kinds of cellulose derivatives on the crystallization and mechanical properties of PHBV were investigated. The crystallization and mechanical properties of PHBV/cellulose derivatives composites were measured by means of differential scanning calorimeter, polarizing microscope, and mechanical properties testing instruments. Studies show that cellulose acetate (CA) can promote the crystallization of PHBV, a small amount of CA can significantly increase the crystallization temperature of PHBV. The crystallization rate of PHBV was also accelerated by CA. However, the addition of cellulose acetate propionate (CAP) and cellulose acetate butyrate (CAB) decreased the crystallization temperature of PHBV and inhibited the nucleation of PHBV. And the degree of inhibition increased with the increase of CAB and CAP content. CAB and CAP have good compatibility with PHBV, CAB, and CAP can be uniformly dispersed in PHBV. Cellulose derivatives with specific component content can enhance the tensile properties of PHBV without losing the impact strength. [ABSTRACT FROM AUTHOR]

This paper presents the synthesis and characterization of graphene–polymer composites, focusing on their mechanical and antibacterial properties. Graphene flakes were obtained via an electrochemical method and integrated into polyamide 6 (PA6) matrices using melt intercalation. Various characterization techniques confirmed the quality of the graphene flakes, including X-ray diffraction (XRD), Raman spectroscopy, and infrared (IR) spectroscopy, as well as scanning and transmission electron microscopy (SEM and TEM) imaging. Mechanical tests showed an increase in the elastic modulus with graphene incorporation, while the impact strength decreased. The SEM analysis highlighted the dispersion of the graphene flakes within the composites and their impact on fracture behavior. Antimicrobial tests demonstrated significant antibacterial properties of the composites, attributed to both oxidative stress and mechanical damage induced by the graphene flakes. The results suggest promising applications for graphene–polymer composites in advanced antimicrobial materials. [ABSTRACT FROM AUTHOR]

Understanding the percolation threshold is essential for determining the performance of particle‐reinforced polymer composites. Spray‐dried cellulose nanocrystals (SDCNC) of micrometer size reinforced homopolymer polypropylene (HPP) composites at 20, 30, 40, and 50 wt.% were prepared to investigate the percolation threshold of SDCNC particles in HPP. The effect of a compatibilizer (maleic anhydride polypropylene (MAPP)) at 3, 5, and 7 wt.%, on the SDCNC percolation networks and composites performance were also studied. The results indicated that SDCNC particle percolation networks in HPP were established between 30 and40 wt.%. For composites without MAPP, the impact strength significantly increased by up to 23% below the percolation threshold and declined beyond it. The peak crystallization temperature of HPP was steadily increased until 30 wt.% SDCNC particles were added due to the SDCNC saturated nucleation function at the threshold. Introducing MAPP significantly improved tensile strength (58%), tensile strain (61%), flexural strength (45%), and impact strength (91%) compared with the corresponding composites without MAPP, attributed to the enhanced interfacial adhesion between the SDCNC particles and HPP. Water absorption results indicated that adding MAPP changed the SDCNC particle distribution networks within the matrix above the percolation threshold but did not change it below the threshold. [ABSTRACT FROM AUTHOR]

Toughening thermo‐setting resins with both high impact strength and tensile strength is a challenging issue. In this study, a novel cross‐linked polyurethane nano spheres for toughening epoxy resin were prepared by self‐emulsification method with hexamethylene diisocyanate trimer (HDI trimer) and diethylene triamine (DETA) as the crosslinkers. The structure, morphology and particle size of cross‐linked polyurethane nano spheres were investigated by infrared spectroscopy, laser particle size analyzer and scanning electron microscopy. Results showed that the prepared cross‐linked polyurethane nano spheres showed spherical shape and had the size in the range from 40 to 258 nm. The application of cross‐linked polyurethane nano spheres in toughing epoxy resin was investigated. The results showed that cross‐linked polyurethane nano spheres can be uniformly dispersed in epoxy resin and no obvious aggregation phenomenon was observed. And the tensile strength and impact strength of epoxy resin can be increased simultaneously when the cross‐linked polyurethane nano spheres were used in toughening epoxy resin. With the increase of the amount of polyurethane nano spheres in epoxy resin, both the tensile strength and impact strength of epoxy resin had the trend of first increase and then decrease. The amount of HDI trimer in the microspheres had a great impact on their toughening effect on epoxy resin. When the cross‐linked polyurethane nano spheres contained HDI trimer content of 12 wt% and the amount of the nano spheres in epoxy resin was 8 wt%, the impact strength of the epoxy resin can reach as high as 23 kJ/m2, which was 4.33 times that of pristine epoxy resin. And the tensile strength of toughened epoxy resin was 50.7 MPa, which was at same level of that of pristine epoxy resin. The results of this study indicate that the cross‐linked polyurethane nano spheres have a great potential in toughening thermo setting resins, such as epoxy resin. [ABSTRACT FROM AUTHOR]

In many different manufacturing techniques, additive manufacturing technologies have proven to be quite useful for developing a prototype model in wide range of applications. In that technique, Fused Deposition Modeling (FDM) is one of the concern favorite methods used in industries, because it can create complex structures at a low cost. FDM uses the polymer ingredients that are melted, extruded, and layered on top of one another to create the desired product, independent of design intricacy. This examination analyzes the effects of several process variables on the flexural and impact characteristics of parts produced of polyethylene terephthalate glycol (PETG)material, including infill structure, layer thinness, infill multi-layering, and infill concentration. The L9 orthogonal array was developed by the Taguchi method to be employed in this design of experiment. Through the analysis of variance (ANOVA), the study elucidated the relative substance and percentage effort of each process parametric quantity to the desired outcomes. The results obtained through the Taguchi method revealed optimal parameters for both impact strength and flexural tests. For impact strength, the optimum factor was determined as a layer thinness of 0.12-millimeter, quarter cubic infill structure, 30% infill denseness (density), and a multi-layering of 3. Conversely, for the flexural test, the optimal factor was found to be a layer thinness of 0.12-millimeter, cross 3D infill structure, 60% infill denseness, and a multi-layering of 4 respectively. [ABSTRACT FROM AUTHOR]

Low-carbon Cr-Ni-Mo steels widely used in mechanical engineering are studied: 18Kh2N4MA, 25Kh2N4MA, 25KhN3MA. Thermokinetic diagrams are plotted by a dilatometric method. Temperature-time ranges for microstructure constituent formation are established. It is shown that bainite within the steels studied may be formed both above and below the Ms temperature. Features of isothermal bainite transformation are investigated, kinetics of bainite transformation are determined, as well as the quantitative ratio of microstructure constituents formed as a result of austempering. It is established that the largest amount of bainite within the steel structures studied (80–95%) is achieved at a temperature near Ms. Mechanical properties (strength, ductility, impact strength) of the steels being studied are analyzed after various heat treatment methods: various cooling intensities, upper and lower bainite austempering. It is shown that formation of upper bainite has an ambiguous effect on steel impact strength. [ABSTRACT FROM AUTHOR]

This article presents research on the influence of reduced graphene oxide on the mechanical properties of silicon carbide matrix composites sintered with the use of the Spark Plasma Sintering method. The produced sinters were subjected to a three-point bending test. An increase in flexural strength was observed, which reaches a maximum value of 503.8 MPa for SiC–2 wt.% rGO composite in comparison to 323 MPa for the reference SiC sample. The hardness of composites decreases with the increase in rGO content down to 1475 HV10, which is correlated with density results. Measured fracture toughness values are burdened with a high standard deviation due to the presence of rGO agglomerates. The KIC reaches values in the range of 3.22–3.82 MPa*m1/2. Three main mechanisms responsible for the increase in the fracture toughness of composites were identified: bridging, deflecting, and branching of cracks. Obtained results show that reduced graphene oxide can be used as a reinforcing phase to the SiC matrix, with an especially visible impact on flexural strength. [ABSTRACT FROM AUTHOR]

Denture fractures are a common problem in dental practice, and their repair is considered a first option to restore their functional properties. However, the inter-material resistance may become compromised. Typically, the bond between these materials weakens. Therefore, various surface treatment methods may be considered to enhance their mechanical properties. Poly(methyl methacrylate) (PMMA) heat-polymerized resin (HPR) was used as the repaired material, cold-polymerized material (CPR) for the repairs, and different variants of alumina abrasive blasting (AB), methyl methacrylate (M), ethyl acetate (EA), methylene chloride (CH), and isopropyl alcohol (IA) treatments were applied. Finally, combined surface treatments were chosen and analyzed. Surface morphologies after treatments were observed by scanning electron microscopy and the flexural, shear, and impact strengths were tested. AB and chemical treatment with CH, M, and EA was used to improve all mechanical properties, and further improvement of the properties could be achieved by combining both types of treatments. Varied changes in surface morphologies were observed. Treatment with IA yielded less favorable results due to the low impact strength. The best results were achieved for the combination of AB and CH, but during the application of CH it was necessary to strictly control the exposure time. [ABSTRACT FROM AUTHOR]

The mechanical strength of 2 film structures, machine-direction-oriented polyethylene (MDO-PE) laminated with linear low-density polyethylene (LLDPE) and polyamide (PA) laminated with LLDPE was evaluated. PA/LLDPE films demonstrated superior impact strength (0.834 J/mm²) compared to MDOPE/LLDPE films (0.445 J/mm²). Tensile strength for modified LLDPE (C6) was 40 N/mm², higher than standard LLDPE (C8) at 33 N/mm². The elongation at break for LLDPE reference C8 was 689 %, compared to 682 % for LLDPE sample C6. Film stiffness was measured at 162 MPa for the LLDPE reference C8 and 122 MPa for the LLDPE sample C6. PA films exhibited increased mechanical strength due to their intrinsic polyamide structure, while MDO-PE films benefited from molecular orientation during production. The modified LLDPE or C6 displayed improved impact resistance and tensile strength with reduced stiffness. MDO-PE/LLDPE films are promising for sustainable and robust food packaging. [ABSTRACT FROM AUTHOR]

Rachis base (RB) (palm fronds base) where the fronds are connected to the trunk the part that is directly attached to the trunk of the palm. Rachis base waste particles had been utilized as natural, innocuous, and non-toxic reinforcement particles to improve the properties of the polyester matrix. The waste particles of the Rachis base waste have been utilized in several particle size and rates. The results demonstrated that the tensile strength had been increased because of the reinforcing process with waste particles of Khistawi Rachis base from 7.76 MPa to 35.04 MPa. As for Young's modulus from 2.38 MPa to 9.55 MPa. Moreover, the impact strength has been increased from (0.03 to 0.165 MPa), while the hardness value from 70.2 (No.) to 76.1 (No.). Finally, the thermal conductivity has increased its value to reach 1.52 W /m.°C, while it was 0.79 W /m.°C for the pure sample [ABSTRACT FROM AUTHOR]

In this paper, the effects of four different types of nucleating agents, namely, α-nucleating agent CH-6N, HPN-715, TMP-7 and β-nucleating agent TMB-5, as well as the effects of compounding of different types of nucleating agents on the mechanical, optical and crystalline properties of polypropylene were investigated. The results show that the nucleating agent can effectively increase the crystallization temperature and crystallinity. α-nucleating agent CH-6N has the best rigidity effect. The bending modulus and bending strength of polypropylene are 2 390 MPa and 60.6 MPa respectively with the addition of 0.2% CH-6N. The α nucleating agent can reduce the toughness of polypropylene. Adding 0.2% CH-6N, the impact strength of polypropylene is only 2.7 kJ/m². The β -nucleating agent TMB-5 can effectively improve the toughness of polypropylene, but reduce the rigidity. The toughening effect of 0.1 % TMB-5 is the best. The impact strength of polypropylene is 20.7 kJ/m2, and the elongation at break is 530%. In terms of optical properties, α nucleating agent CH-6N has the best modification effect, and after the addition of 0.1% CH-6N, the yellow index of polypropylene is only 0.46. The combination of α nucleating agent and β nucleating agent can not only improve the toughness of polypropylene, but also improve its rigidity, and achieve the balance of rigidity-toughness. The compound modification effect of 0.1% CH-6N and 0.1% TMB-5 is good, and the impact strength of polypropylene is 5.5 kJ/m², the bending modulus is 2 140 MPa, and the tensile strength is 41.1 MPa. [ABSTRACT FROM AUTHOR]

In order to improve the mechanical properties and thermal stability of nylon 66 (PA66) and make it widely used in the field of automotive lightweight, 5%~20% carbon fiber (CF) was doped in PA66 matrix. The results show that the PA66 composite doped with 15% CF has better comprehensive properties than the unmodified PA66 material. The universal testing machine test shows that the tensile strength of PA66/15% CF is 180 MPa, increased by 177%, and the elastic modulus is 19 867 MPa, increased by 7.1 times. The bending strength is 262 MPa, which is increased by 212%, and the bending modulus is 15 867 MPa, increased by 6.4 times. The impact strength of PA66/15%CF is 12.7 kJ/m², which increases by 49.4%. The mass residual rate of PA66/15%CF composite is 22.8%, and the thermal stability of the material is significantly improved. The study indicates that CF-modified PA66 composites have the potential for use in the field of automotive light weighting, with a 15% doping amount being preferable. [ABSTRACT FROM AUTHOR]

Graphite oxide (GO) was used to modify polycarbonate (PC) to prepare flame retardant PC composites and the effects of GO content on the flame retardancy, mechanical properties, and heat resistance of composites. The results showed that the flame retardancy and heat resistance of composites increased with the increase of GO content, and the tensile strength, bending strength, and impact strength of the composites continued to increase, while the elongation at break gradually decreased. When the GO content is 3%, the composites with good flame retardancy, mechanical properties, and heat resistance can be obtained. At this time, the limited oxygen index (LOI) of the composites reaches 32.8%, the flame retardancy level reaches V-0, and the total heat release (THR) and total smoke production(TSP) are reduced by 45.8% and 75.7%, respectively. Compared with pure PC, the tensile strength, bending strength, and impact strength are increased by 25.4%, 33.7%, and 63.2%, respectively, the elongation at break is reduced by 7.1%. The temperature at which the weight loss is 5% is increased by 19 °C, the peak temperature of thermal weight loss is increased by 52 °C, and the mass residual rate of thermal decomposition is increased by 8.9%. [ABSTRACT FROM AUTHOR]

POE was used to modify polypropylene (PP) to improve paint adhesion on the surface of PP material for automotive interior. By means of differential scanning calorimetry, scanning electron microscope, Dyne pen, Paints Crosscut test and mechanical property test, the effects of POE on crystallization property, dispersion ability, surface tension, paint adhesion and mechanical properties of modified PP were investigated. The results show that with the increase of POE, the tensile yield strength and bending modulus of modified PP decrease, and the notch impact strength increases. The higher melt flow rate (MFR) of POE, the greater the reduction of rigidity. The higher the content of POE, the more favorable it is to improve the surface adhesion of modified PP. When the POE content is not less than 15%, the Paints Cross-cut test level of the template reaches 0. The higher the MFR of POE, the more conducive to the orientation and dispersion of the rubber phase on the surface of the template, which is conducive to the immersion of the paint and the improvement of the paint adhesion. When the paint film thickness is less than 26 μm, it is difficult to form an effective and dense paint film on the surface of the template, resulting in poor paint adhesion of the template. When the paint film thickness is not less than 26 μm, the template paint adhesion is better. [ABSTRACT FROM AUTHOR]

Crosslinking modification is one of the important methods of polyethylene modification. The effects of crosslinking degree and resin structure on rheological properties, crosslinking properties, crystallization properties and mechanical properties of crosslinked high density polyethylene (XHDPE) were studied. The results show that when the mass fraction of crosslinking agent increases from 0 to 1.2%, the maximum energy storage modulus (G'max) and gel content of XHDPE increase, and the minimum value of loss factor (tanδmin) decreases gradually. With the increase of the content of crosslinking agent, the crystallinity and grain size of XHDPE decreases, and the crystallization capacity decreases. After the addition of crosslinking agent, the tensile yield strength of XHDPE decreases gradually, the elongation at break increases first and then decreases, and the impact strength increases significantly. With the same content of crosslinking agent, the energy storage modulus of XHDPE and the viscoelasticity of macromolecular network increase gradually with the increase of molecular weight of base resin. When the elongation at break of high molecular weight HDPE reaches the maximum, the content of crosslinking agent required is lower. High molecular weight HDPE base resin is beneficial to improve the mechanical properties of crosslinked samples. [ABSTRACT FROM AUTHOR]

Flax fibre-reinforced bio-composites are developed using both unmodified petroleum-based epoxy and Epoxy Methyl Ricinoleate (EMR) toughened epoxy modified with microcrystalline cellulose (MCC) as the base matrix. Base-catalyzed transesterification is employed for the synthesis of EMR as a low-viscosity reactive green monomer for the modification of petroleum-based epoxy. MCC is incorporated into the EMR-modified epoxy through mechanical stirring and subsequent sonication at loading rates of 1%, 3%, and 5% by weight. The compression molding technique was employed to prepare the composites. The results show an enhancement in tensile strength, modulus, impact strength, and inter-laminar shear strength values up to 19%, 34%, 34.2%, and 22.7%, respectively for MCC filled EMR toughened epoxy composite compared to neat epoxy composite. The storage and loss moduli, as revealed by the dynamic mechanical analysis (DMA), also demonstrate improvement for the 3% MCC-C composite signifying the improved fibre/matrix bonding. The low-velocity impact test at 10 J and 20 J for non-perforation and perforation conditions was also performed on the composites. The MCC-incorporated EMR-modified composite demonstrated the highest low velocity impact resistance among all other bio-composites, highlighting its potential for use in semi-structural applications due to the enhanced interfacial adhesion. The SEM analysis revealed that the fibre surface of MCC-modified EPEMR20 composites exhibited surface damage, and adherence of MCC fillers and matrix fragments, indicating superior adhesion to the matrix system. [ABSTRACT FROM AUTHOR]

This study aimed to assess the possibility of using post-production waste and the impact of the conditioning method on the mechanical and thermomechanical properties of polyamide injection molded parts. Samples containing 5, 10, and 15 wt.% of ground post-production waste were produced using injection molding technology. The rheological properties by oscillatory rheometry, the melt mass flow rate (MFR), and the thermal stability by thermogravimetric analysis (TGA) of polymer mixtures containing recycled fraction were determined. The samples were conditioned under the following conditions: 24 h and 14 days in distilled water, in a climatic chamber, and aged in a xenon-light-accelerated aging chamber. Then, the impact and static tensile strength and heat deflection temperature (HDT) were assessed. The results show that the addition of post-production waste in the form of grinding does not significantly affect the mechanical and thermomechanical properties of the finished products. This research provides valuable information regarding the possibility of using secondary materials for manufacturing high-performance construction products. Moreover, it was proven that the process of conditioning polyamide samples in a climatic chamber was the most effective and significantly increased the impact strength of the tested material. [ABSTRACT FROM AUTHOR]

Abstract One of the primary drawbacks associated with natural fiber reinforced composites is their relatively poor mechanical properties. One potential approach to overcome this challenge is to augment the fiber loading, thereby improving the interfacial characteristics and hybridization. In this study, hybrid polyester composite structures reinforced with jute/hemp fibers were fabricated via the hand layup process, with fiber loadings varying between 30%, 50%, and 70% by volume. Fibers were subjected to alkali solutions (NaOH) containing 3% and 5% alkali in advance of the composites' formation. The impact, flexural, and tensile characteristics of hybrid jute/hemp reinforced polyester composites were investigated via laboratory studies. The composite materials that underwent testing with a 50 vol% fiber loading and 3% NaOH exhibited the maximum tensile strength (26.6 MPa), tensile modulus (733.56 MPa), flexural strength (62.7 MPa), and flexural modulus (3.04 GPa). Highlights Hybrid polyester composite structures reinforced with jute/hemp fibers were fabricated. Hand layup method used with various fiber loadings (30%, 50%, and 70% by volume). Highest mechanical properties were obtained for 3% NaOH treatment and 50% fiber loading.

Epoxy resins (EPs) are highly coveted as insulating materials for engineering applications. However, their limited mechanical properties and inadequate thermal conductivity at cryogenic temperatures significantly restrict their range of applications. Herein, a novel approach was introduced for crafting EP composites infused with boron nitride (BN) using hyperbranched polymer (HBP) grafting. The resulting HBP‐BN was uniformly dispersed within the EP and securely bonded to the matrix through robust chemical interactions, significantly improving the property enhancement efficiency of HBP‐BN on EP. Thus, the mechanical strength of EP/HBP‐BN composites was significantly enhanced, with maximum tensile and impact strengths achieved at 6 and 4 wt% HBP‐BN content. These values exceeded those of pure EP by 47% and 22% at room temperature (RT) and increased even more substantially to 72% and 135% at 77 K. Moreover, the composite demonstrated a remarkable 430% improvement in thermal conductivity, reaching 1.1627 W·m−1·K−1, when the HBP‐BN content reached 40 wt%. Simultaneously, EP/HBP‐BN composites exhibit low dielectric permittivity and high volume resistivity, signifying exceptional electrical insulation properties. HBP‐BN substantially enhances the cryogenic properties of EP composites, offering an efficient pathway for the utilization of EPs in engineering applications. Highlights: A novel method to enhance the cryogenic properties of EP was introduced.HBP‐BN significantly improves the cryogenic properties in EP composites.The composites are of significant interest for various engineering applications. [ABSTRACT FROM AUTHOR]

This research investigates the enhancement effects of basalt fibers (BFs) and kraft lignin (KL) as natural additives on the mechanical properties of acrylonitrile–butadiene–styrene (ABS)‐based composites. Initially, BF was incorporated into ABS as a fiber reinforcement, and its mechanical properties were evaluated. It was observed that an increase in BF content in ABS led to an increase in the tensile strength while the impact strength tended to decrease. Subsequently, the potential of lignin or modified lignin as interfacial compatibilizers was assessed to improve the miscibility between ABS and BF. The modification of lignin was achieved via esterification by using esterifying agents (acetic anhydride [C2_Ac], propionic anhydride [C3_Pr], and butyric anhydride [C4_Bu]). At the optimal conditions (30 wt% of BF, 15phr of AcKL), the mechanical properties of ABS/BF/AcKL composite presented a 48.1% improvement in tensile strength and a 27.4% enhancement in impact strength compared to those of ABS/BF composite. The fracture surface analysis of the composite revealed that the esterified lignin enhances the compatibility between components, thereby filling the gaps present at the matrix‐fiber interface. These results suggest promising applications for multi‐component composite materials. [ABSTRACT FROM AUTHOR]

Acrylonitrile‐EPDM‐styrene (AES) was applied as an impact modifier for poly(lactic acid) (PLA), and the combined effect of dicumyl peroxide (DCP) crosslinking and annealing heat treatment was investigated. Torque rheometry, melt flow index (MFI), mechanical properties (impact, tensile, and Shore D hardness), X‐ray diffraction (XRD), infrared spectroscopy (FTIR), heat deflection temperature (HDT), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) were investigated. There was a considerable torque increment and fluidity drop in the PLA/AES/DCP blends caused by the crosslinking process and the formation of PLA‐g‐AES. Consequently, the impact strength and elongation at break properties improved. As an engineering terpolymer, AES was decisive in maintaining high elastic modulus, Shore D hardness, and HDT values. The PLA/AES/DCP (0.8 phr) composition leaned towards a synergism of mechanical properties, gaining 505.6% and 264.8% in impact strength and elongation at break, respectively, compared to neat PLA. FTIR and XRD analysis revealed high crystallinity, with samples presenting large crystals. The higher crystallinity had a deleterious effect on the mechanical properties of the PLA/AES/DCP blends. However, there was a marked improvement in HDT and higher toughness compared to PLA. The results before and after annealing the PLA/AES/DCP (0.8 phr) blend are promising for constructing new semi‐biodegradable materials for additive manufacturing. [ABSTRACT FROM AUTHOR]

In recent years, researchers and scholars have shown growing interest in exploring the applications of natural fibers in polymer composites, driven by their environmentally friendly and sustainable characteristics. This study endeavors to offer an exhaustive examination of the prominent and widely adopted natural fiber reinforced polymer composites and their diverse range of applications. Furthermore, it provides an overview of different surface treatment methods applied to natural fibers and their influence on the properties of, highlighting the significant variations in properties depending on the fiber type, source, and structure. Bamboo fibers (BF) and recycled chemically functionalized acrylonitrile-butadiene-styrene (r-ABS) composites (BF/rABS) have been blended at 190°C. The composites show a higher tensile and flexural properties than r-ABS. The presence of bamboo fibers functions as stress concentrators, resulting in minimized deformation and consequently reducing the impact strength of the composites in comparison to the matrix. The SEM and FTIR analysis have shown that the adhesion between fiber and the matrix is good which therefore improves the tensile properties of the composite materials. XRD analysis has shown improved crystallinity in composite as compared to matrix. [ABSTRACT FROM AUTHOR]

The article discusses an experimental procedure which involves impregnating cinnamon extracts into Poly Methyl Methacrylate (PMMA) resin with further purpose of utilizing it for dental prosthesis purposes. At normalized sampling rates and through manual molding using 53μm particle size, samples comprising of 8%, 6%, 4%, 2% and 0% volume fractions were evaluated. Mechanical properties such as hardness, impact strength, and tensile strength were also investigated empirically. The findings demonstrated an increase in hardness, reaching a maximum level of 8% with a value of 86 N/m². Also, impact strength coefficient marked rather a positive effect, with 0.93 KJ/m² being the highest peak noticed at the 6% volume fraction level. The peak value of tensile strength was successfully measured at 4% by volume fraction that gave 52 MPa, while additional ratios of reinforcement had a continuous trend of a decrease. This thorough study uncovers the future promising potential of cinnamon extracts as to the reinforcement of technical properties (mechanical properties), and this contributes to the improvement of modern biomaterials used in Dentistry. [ABSTRACT FROM AUTHOR]

In the present study, electrostatic powder coating waste was recycled and employed to reinforce high‐density polyethylene. The hydrolysis method was preferred to modify the powder coating waste of various systems, and they were mixed with high‐density polyethylene at various weight ratios. The mixtures were prepared in a mechanical mixer and then in an extruder to obtain a homogeneous mixture. This homogeneous structure was pressed into molds with a plastic injection device to obtain standard tensile samples. Mechanical and thermal tests were conducted on the samples. It was determined that the tensile stress of the sample decreased with the increase in filler content. The changes in sample tensile strength were investigated after the samples were aged. Three‐point bending strength of the samples was also investigated and it was observed that they became more resistant to vertical loads as the filler content increased. The Izod impact strength of the samples differed based on the filler type and weight ratio. Furthermore, mass loss in the produced mixtures was determined with thermogravimetric analysis. The matrix and filler bonding mechanisms were observed under an electron microscope. [ABSTRACT FROM AUTHOR]

This study investigates the mechanical properties of nonwoven hybrid composites made from recycled cotton/polyethylene terephthalate (PET) with various fiber weight percentages (100/0, 0/100, 75/25, 60/40, 50/70, 60/40, and 25/75). The multilayered nonwoven carded webs are manufactured by the carding machine, while the manual lay‐up technique is used to fabricate nonwoven‐reinforced composites. Their tensile, flexural, and impact properties and microstructure are then examined. It is found that the tensile modulus and strength increase with the increase in cotton, while the impact strength improves with the increase in PET. The composite of 75% cotton/25% PET offers 92.13% and 67.87% higher tensile modulus and strength than the composite of 25% cotton/75% PET; however, the composite of 25% cotton/75% PET shows 83.09% and 36.22% higher flexural modulus and strength, and 187% more impact strength, respectively, than the composite of 75% cotton/25% PET. The outcome of this study indicates that nonwoven composites with higher contents of recycled cotton can potentially be applied in building and construction sectors where substantial tensile strength is necessary, while composites with comparatively higher contents of recycled PET may be used for various potential applications (e.g., helmets, surfboards, and automotive interiors) where significant flexural and impact strengths are required. [ABSTRACT FROM AUTHOR]

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In energetic materials, high-energy propellants always encounter poor mechanical properties. Herein, a novel energetic binder nitrate glycerol ether cellulose (NGEC)/hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) composite was prepared by a facile, safe water suspension and freeze-drying technology, and integrated in gun propellant (GP) through semi-solvent manufacturing. A series of characterizations and tests were conducted to characterize the NGEC/RDX-GP. The findings revealed that the mechanical properties in terms of the impact strength of NGEC/RDX-GPs with different content of NGEC was improved by 15.3% ~ 117.1%, 3.9% ~ 34.6%, 6.9% ~ 31.1% under conditions of -40 °C, 20 °C and 50 °C; the compression strength was improved by 2.5% ~ 23.1%, 10.7% ~ 27.9%, 7.3% ~ 28.5%, while the tensile strength was improved by 15.4% ~ 35.0%, 10.4% ~ 33.0%, 11.8% ~ 35.5%, respectively. Besides, the thermal decomposition dynamics and thermodynamics were also investigated to probe the thermal properties of NGEC/RDX-GP. Moreover, the impact and electrostatic spark sensitivity have also been tested and present excepted results compared with neat propellant. In addition, the improved gunpowder impetus of NGEC/RDX-GP indicated that the energetic performance of propellant was further enhanced, and maintained stable combustion behavior. Finally, the enhancement mechanism of the propellant was discussed and proposed. Therefore, this construction strategy and application of NGEC/RDX composites in propellants can provide reliable fundamental theory and data support for the development of high performances propellant. [ABSTRACT FROM AUTHOR]