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A large amount of toxic smoke and heat generated by the combustion of ethylene vinyl acetate copolymer (EVA) poses a significant threat to human fire escape evacuation. This work aims to use γ -ray to prepare e-MXene@Ag hybrid flame-retardant materials by the method of in-situ reduction, and EVA composites are prepared by melt blending to reduce the smoke and toxic gases produced during combustion significantly. Compared with pure EVA, the total heat release, total smoke release, and the production rate of CO and CO2 produced by the combustion of EVA composite with 1 wt% e-MXene@Ag1.0 decreased by 30.3%, 33.3%, 18.2%, and 20.1% respectively. The fire hazard reduction of EVA composite materials was due to the physical barrier, catalytic carbonization and adsorption of the e-MXene@Ag1.0 hybrid. In addition, e-MXene@Ag1.0 can also further increase the mechanical properties of EVA composites due to its own 'multi-contact point limit structure'. [ABSTRACT FROM AUTHOR]

Highlights This research endeavors to explore the potential of annealing treatment as a viable strategy to optimize the utilization of polypropylene (PP) composites, while preserving their exceptional properties. By incorporating ethylene vinyl acetate (EVA) copolymer and layered double hydroxide (LDH) into PP, this work meticulously analyzes the changes in crystallization behaviors and impact properties under varying annealing conditions. Impact strength is systematically assessed by a digital pendulum impact tester, whereas the crystalline structure is analyzed through polarized light optical microscopy (POM), differential scanning calorimetry (DSC), and x‐ray diffraction (XRD). The notch impact test exhibits a gradual increase in impact strength from 100 to 130°C, followed by a decline at 140°C. The XRD and DSC results elucidate subtle β‐crystal diffraction peaks for PP/EVA and PP/EVA/LDH composites, attributed to the transformative effect of EVA and LDH on PP crystals. POM analysis further unveils a reduction in spherical crystal size and gradual blurring of grain boundaries during the annealing process. PP/EVA/LDH composites are effectively regulated by changing the annealing treatment conditions. The crystallization behaviors and crystal structure of PP are induced due to synergistic effect of EVA and LDH under annealing treatment. The toughness of PP is enhanced significantly by synergistic effect of EVA and LDH under annealing treatment. [ABSTRACT FROM AUTHOR]

The impact of adding ethylene vinyl acetate copolymer (EVA 80) and 1 wt% TiO2 nanoparticles on the morphology and crystallization behavior of poly(lactic acid) blends was investigated using DSC, SEM, and POM. Thermal analysis revealed the enhancement of crystallinity of PLA in the presence of TiO2 and higher EVA 80 content in the blend. The PLA and EVA 80 components showed compatibility, as evidenced by the shift of the glass transition temperatures of the PLA phase in the blend to lower values compared to neat PLA. The lower temperature shift of the cold crystallization of the PLA and the formation of the small spherulites of the PLA in the blends indicated that the EVA 80 and TiO2 act as a nucleating agent for crystallization. The non-isothermal crystallization parameters of the composites were evaluated using Avrami's modified model, the MO approach, and Friedman's isoconversional method. The Avrami's modified rate constant (K) and the effective activation energy values significantly increased with the incorporation of EVA 80 and TiO2 nanoparticles. Furthermore, the thermogravimetric analysis (TGA) showed improved thermal stability of PLA by adding EVA 80 and TiO2. [ABSTRACT FROM AUTHOR]

Recently reported direct growth of highly crystalline centimetre-sized black phosphorus (BP) thin films on mica substrates by pulsed laser deposition (PLD) has attracted considerable research interest. However, an effective and general transfer method to incorporate them into (opto-)electronic devices is still missing. Here, we show a wet transfer method utilizing ethylene-vinyl acetate (EVA) and an ethylene glycol (EG) solution to transfer high-crystalline large-area PLD-BP films onto SiO2/Si substrates. The transferred films were used to fabricate BP-based bottom-gate field-effect transistor (FET) arrays exhibiting good uniformity and continuity, with carrier mobility and current switching ratios comparable to those obtained in as-grown BP films on mica substrates. Our work presents a promising transfer strategy for scalable integration of on-substrate grown 2D BP into devices with more complex structures and further investigation of material properties. Black phosphorus (BP) is a 2D semiconductor with potential for (opto-)electronic applications, but its large-scale integration with Si substrates is challenging. Here, the authors report a method to transfer cm-scale BP films onto SiO2/Si substrates retaining their uniformity and electrical properties. [ABSTRACT FROM AUTHOR]

The study investigated the effect of paraffin wax, expanded graphite, and their dispersion on the properties of the blend of polypropylene (PP) and ethylene vinyl acetate (EVA). The idea is to reduce interfacial tension in blends of PP and EVA while enhancing the properties of blends in the process. The chosen optimum contents of the paraffin wax and EG in the 80/20 PP/EVA blend were 10 and 6 wt.%, respectively. The morphological features show that the expanded graphite (EG) particles had high affinity for each other. Moreover, EG filler particles are localized inside the minor EVA phase and some at the interface. Rheological properties revealed that the flow of the binary composites increased when 10 wt.% wax is added suggesting that wax enhanced the processability of the composites. The Cole-Cole plots deviated from the semi-circular arc suggesting heterogeneity in the blend and PP/EVA/Wax/EG composite. The addition of paraffin wax and EVA delayed crystallization of PP, while earlier crystallization of PP was promoted by the presence of EG. Generally, all samples caught fire after 10 s, started dripping and are thus given a V-2 rating according to the Underwriters Laboratories test standard 94 results (UL-94). [ABSTRACT FROM AUTHOR]

Microplastic (MP) pollution has gained considerable attention in various ecosystems; however, it has received relatively less attention in freshwater‐riverine environments than in other ecosystems. The Ganges River Delta, one of the world's most densely populated areas, is a potential source of MP pollution in the freshwater ecosystem. MPs were identified throughout the year in the lower Ganges River water. Seasonally, the highest abundance was observed during the monsoon (14.66 ± 2.06 MPs/L), followed by the pre‐monsoon (13.46 ± 1.75 MPs/L) and post‐monsoon (11.50 ± 0.40 MPs/L). Throughout the year, MP discharge was estimated at 4.12 × 1012 to 2.17 × 1013 MPs/year. Fourier transformed infrared spectroscopy identified plastic polymers in the water, like ethylene vinyl acetate, polystyrene, polypropylene, polyethylene, and nylon. Moderate contamination by MPs was assessed throughout the year. Significant correlations between MP abundance and both rainfall and discharge were observed. It is essential to implement preventative measures in the Ganges River Basin to mitigate MP pollution before the situation worsens. Practitioner Points: Throughout the year, MP concentration ranged from 10.67 to 20.33 MPs/LThe highest MP occurrence was observed in the monsoon season (14.66 ± 2.06 MPs/L)The lowest abundance was detected in the post‐monsoon period (11.50 ± 0.40 MPs/L)There was a moderate level of MP contamination in the lower Ganges River waterIt was shown that discharge and rainfall were correlated with MP abundance [ABSTRACT FROM AUTHOR]

Perianaesthetic dental trauma is a common anaesthesia-related complication. Theprevious studies have shown a lack of knowledge regarding mouthguard usage and controversial results related to perianaesthetic dental trauma prevention. This study aimed to conduct a finite element analysis of the compressive and tensile stresses on the tooth-periodontal ligament-bone complex using custom-made mouthguards of different thicknesses and glass fibre splints to prevent perianaesthetic dental trauma. Custom-fitted ethylene-vinyl acetate mouthguards of two different thicknesses (2 and 3 mm) and glass fibre splint were modelled. A linear static finite element analysis was performed by applying a rigid Macintosh laryngoscope to the palatal surface of the maxillary central incisors at 150 N. The model without a mouthguard and glass fibre splint showed the highest stress values at the palatinal root surfaces during the impact. Increasing the mouthguard thickness significantly decreased the stress-strain values regardless of the presence of the glass fibre splint. Maximum stresses in the group using the 3 mm mouthguard were the lowest compared with the other groups. [ABSTRACT FROM AUTHOR]

Polyethylene (PE) is susceptible to environmental stress cracking (ESC). In the presence of an amphiphilic compound and subjected to stress, ESC starts with cavitation followed by slow crack growth and ends with brittle fracture. In this study, we used molecular dynamics simulation to study how branch ends which were chemically modified with vinyl acetate groups affect free volume coalescence around an amphiphilic compound, nonyl ethoxylate (NE), dispersed in branched PE models. Branch ends modified with vinyl acetate significantly impact the free volume coalescence dynamics around NE. Compared with methyl branch ends, vinyl acetate branch ends show a much higher affinity, as quantified by the corresponding radial distribution functions, for the hydrophilic ethylene oxide‐segment of NE. However, this is not the case for the hydrophobic ethylene‐segment. Interestingly, vinyl acetate branch ends tend to reduce the power (amplitude) of the free volume size fluctuations around both the ethylene oxide‐ and ethylene‐segments. Indeed, the powers of the fluctuations with different PE branching characteristics decrease with increasing vinyl acetate concentration. We believe that free volume coalescence leads to cavitation and that vinyl acetate branches could inhibit cavitation, thereby crack propagation in PE. The power results seem to be consistent with the experimental observation that the addition of copolymer ethylene vinyl acetate to low‐density polyethylene improves the ESC resistance of the blend. Highlights: Vinyl acetate branches reduce free volume coalescence activities.Vinyl acetate branches are attracted to the hydrophilic segment of NE.Cavitation likely starts from the free volume coalescence around NE. [ABSTRACT FROM AUTHOR]

Biocomposting at national and regional levels has recently been recognized as one of the feasible, nature-based solutions to prevent the accumulation and reuse of biodegradable waste in enhanced and effective mitigation measures for urban and semi-urban waste management. Recent research has mainly focused on organic compost contamination, as the negative effects of MP on soil systems have been extensively studied. According to current research, organic compost used as fertilizer on farmland contains many microplastics. In this context, microplastics (MPs) have been regarded as a global environmental problem and an emerging soil contaminant. The physico-chemical properties of water and compost samples were analyzed by APHA and AOAC methods. The extraction of microplastics was done using the density separation. In the current study, agricultural waste-based biocompost and water samples used for the production of biocompost were collected from four different agricultural nurseries in semi-urban areas of the Coimbatore city. The physicochemical properties (including heavy metal content) of the biocompost and water samples tested were on par/equal/lower than Indian standards. Interestingly, in the biocompost samples, 85% of the microplastic fragments and 15% of the fiber types were identified only in BC-B and BC-C, respectively, with different colors such as red, brown, blue, light yellow and transparency. However, no microplastics were found in the biocompost samples of BC-A and BC-D. Microplastic polymers such as polymethyl methacrylate (PMMA), polypropylene (PP), and ethylene vinyl acetate (EVA) were identified through ATR-FTIR analysis. The results suggest that semi-urban agricultural gardening may lead to the accumulation of microplastics in terrestrial environments, which may negatively impact soil and plant health. This study contributes to growing research into microplastic contamination in organic compost and its potential impact on agriculture and terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

Since buildings are designed to endure over time, it is crucial to comprehend how laminated glass (LG) windows, and consequently, the polymer interlayer materials, respond to weathering. This paper explores the impact of accelerated humidity on the mechanical properties of several polymer interlayer materials and LG sections. The study specifically focuses on three polymer interlayer materials of industrial interest: polyvinyl butyral (PVB), ethylene-vinyl acetate (EVA), and ionomer (SG). To examine the environmental effects, testing setups were devised to subject the polymeric materials and LG panels to specific conditions. Uniaxial tension coupons and LG disks were submerged in a water bath to simulate the environmental effect. A dedicated testing fixture was designed and manufactured for the LG disks. The results showed that the properties of EVA, including strength, maximum strain, and toughness, were not significantly affected by the environmental conditions. However, the properties of SG5000 were notably impacted, with a significant reduction in its bond strength due to water immersion. [ABSTRACT FROM AUTHOR]

It is known that the bonding strength of the aggregate/cement interface affects the overall durability of concrete. However, whether the modification of ethylene vinyl acetate (EVA) copolymer affects the interface interaction between aggregates and cementitious materials is unclear. This study analyzed the interface's static structure, dynamic characteristics, and binding energy. The interaction mechanisms between acid and alkali aggregates and hydrated calcium silicate and the modification effect of EVA were compared. The calculation results of relative density distribution and radial distribution function verified the difference in the structure of EVA-modified acidic or alkaline interfaces. EVA polymer chains significantly blocked the flow of Ca atoms in CaO at the CaO/C-S-H interface and weakened the van der Waals effect at the interface. The mean square displacement and time correlation function analysis indicate that all unmodified interfaces have stable interface structures. After EVA modification, the stability of CaCa-HW decreased significantly, hindered the generation of hydration products, and verified the weak Ca atom transport at the CaO/C-S-H interface. In addition, the adhesion energy of SiO2/C-S-H and CaO/C-S-H after EVA modification decreased by 6% and 14.8%, respectively, quantifying the modification effect of EVA. [ABSTRACT FROM AUTHOR]

Ethylene‐vinyl acetate (EVA) hot‐melt adhesives featured good thermal stability, strong weather resistance and fast bonding speed, are of great concern to the industry and engineering fields. However, the weak bond strength and poor reusability severely hinder their application under harsh conditions. Herein, the hydrolyzed EVA (EVOH) copolymers with rich hydroxyl groups are fabricated by an EVA hydrolysis reaction, and their mechanical properties, environmental adaptability, and reusability were systematically evaluated. As a result, the shear strengths measured by bonding the stainless steel plates can reach up to 16.4 MPa at room temperature (25°C) and 13.1 MPa at ultra‐low temperature (−196°C), indicating the good bonding performance of EVOH. Besides, owing to the excellent dynamic reversibility and thermal stability, it can obtain 92% of shear strength retention rate after 10 reuses, which is the highest value reported so far. In addition, the hydroxyl‐rich EVOH delivers good solvent and corrosion resistance that can be widely used for bonding various materials. Therefore, this research provide new lightspots for developing environmentally friendly hot‐melt adhesives with excellent bonding properties, corrosion resistance, and reusability. [ABSTRACT FROM AUTHOR]

Microwave-absorbing materials are widely used for electromagnetic interference shielding and stealth technology. However, most existing materials are heavy, rigid, and expensive, limiting their practical applications. Therefore, there is a need to develop new materials that are flexible, lightweight, and cost effective. This study aimed to synthesize and characterize a novel ternary composite material based on polyaniline (PAni), carbon nanotubes (CNTs), and graphene nanoplatelets (GNPs) in an ethylene-vinyl acetate (EVA) copolymer matrix. PAni-based ternary composites were prepared by in situ polymerization of aniline in toluene dispersion of CNT/GNP hybrids and EVA. The microwave absorption properties were evaluated using a vector network analyzer in the frequency range of 8.2–18 GHz. The presence of as little as 0.8 wt% of CNT/GNP hybrid with appropriate mass ratio increased the conductivity by more than four orders of magnitude compared to the EVA@PAni blend. The minimum reflection loss corresponded to -40.55 dB at 16.31 GHz for the system containing CNT/GNP = 0.3:0.7, whereas those with CNT/GNP = 0.0:1.0 and 0.7:0.3 presented the widest effective absorption bandwidths (RL < (10 dB), covering almost the entire Ku-band. Due to the excellent flexibility, low weight, and high microwave absorption performance, these composites are potential candidates for microwave absorption applications. [ABSTRACT FROM AUTHOR]

The aim of the present study is to use beech wood flour (WF) and expanded ethylene vinyl acetate (EVA) copolymer industrial waste to develop a sustainable composite and its production method for further engineering use. Polyamide (PA) powder waste obtained after multiple selective laser sintering (SLS) thermal cycles was used to increase the strength and adhesion between the waste composite components. The morphological, mechanical, and thermal properties of the EVA/WF composites were characterised along with their interfacial wetting and water absorption properties. Optical and electron microscopy investigations revealed that the composites prepared have homogeneous dispersion and good interfacial adhesion between EVA and wood. The addition of SLS waste PA powder increases the strength and stiffness of the composite developed. The composite with 40 wt% WF exhibited the best water absorption, mechanical properties, and processability among the various compositions. The sustainable composite proposed can replace commercially available materials, which helps to save resources and reduce waste. [ABSTRACT FROM AUTHOR]

The utilization of calcium sulfoaluminate (CSA) cement, known for its rapid strength gain and low carbon footprint, has been increasingly prevalent in the field of construction. This research aims to enhance the mechanical properties of CSA cement-based materials by incorporating ethylene-vinyl acetate (EVA) and styrene acrylate ester (SAE) copolymers. Various dosages (expressed as mass fractions) of EVA and SAE were utilized in the production of CSA cement pastes. The fluidity, setting time, electrical resistivity, and mechanical properties, including flexural strength, compressive strength, and drying shrinkage behavior, were thoroughly assessed for the CSA cement pastes, and the products of hydration in the cement pastes were analyzed. The findings suggest that the inclusion of polymer emulsions in CSA cement pastes resulted in prolonging setting time and hindering hydration. While the addition of SAE did not enhance flexural and compressive strength, the incorporation of 10% SAE effectively reduced drying shrinkage and significantly improved the flexural-to-compressive strength ratio of the CSA cement pastes after 6 h. When the SAE content reached 5%, the fluidity of cement paste could be effectively increased. On the other hand, the inclusion of EVA improved the early-age flexural strength at 6 h but did not effectively reduce drying shrinkage in the CSA cement pastes. When 5% EVA was used, the 28-day compressive strength exceeded that of the control sample (with no polymer). [ABSTRACT FROM AUTHOR]

This study prepared modified alkali-activated slag repair materials by incorporating an ethylene-vinyl acetate copolymer emulsion (EVA). Sulfate attack tests, shrinkage tests, scanning electron microscopy, and mercury intrusion porosimetry tests were conducted to examine the durability and microstructural features of the alkali-activated slag repair materials. The experimental results demonstrated that adding EVA can enhance the shrinkage and strength of alkali-activated slag mortar, but that the materials exhibit poor resistance to sulfate attack. Optimizing the ratio design can yield alkali-activated cementitious materials with high strength, good durability, high bonding strength, and low shrinkage. This can reduce brittleness and increase the shrinkage rate of the material's defects, which has significant implications for subsequent fracture repair. The image of the microstructure showed that the section of alkali-activated slag paste is smooth and exhibits polymer emulsion filling gaps in the amorphous cementitious material. A connection between fibrous filaments on the cross section of the matrix crack enhances the strength of the material. The proportion of microcracks is increased and material strength is decreased after sulfate attack. [ABSTRACT FROM AUTHOR]

We have investigated a self-healing thermally conductive Ethylene-vinyl acetate (EVA) hot melt adhesive (NAEDS, which denotes the addition of nano-alumina and disulfide bonded EVA hot melt adhesives) that can be used to effectively solve adhesive layer separation problem in photovoltaic (PV) modules and the difficulty of recycling. More specifically, we used diallyl disulfide as a cross-linking agent for EVA and alumina nanofillers as a reinforcing phase. The nano alumina filler gave the EVA better thermal conductivity. We used FTIR, SEM, and DSC to characterize and analyze NAEDS properties. The disulfide bonds in NAEDS underwent a rearrangement reaction under ultraviolet light, resulting in the self-healing of the resin (self-healing efficiency of 78.8%). The added nano alumina not only reduced the resin curing activation energy, improving its curing performance but also enhanced its thermal conductivity, achieving a 2.61 W/(m*k) thermal conductivity coefficient. The overall NAEDS performance is improved. [ABSTRACT FROM AUTHOR]

All‐solid‐state lithium batteries (ASSLBs) are considered a promising technology for next‐generation energy storage systems due to their inherent safety. However, the conventional laboratory‐scale ASSLBs reported to date are based on pellet‐type structures with thick solid electrolyte layers, leading to challenges related to low energy densities and poor electrochemical performance. In this study, porous adhesive poly(ethylene vinyl acetate) (PEVA) scaffolds and polytetrafluoroethylene (PTFE) binders are utilized to interweave sulfide solid electrolytes into freestanding films with an ultra‐low thickness of 40 µm, high ionic conductivity of 1.1 mS cm−1, and a high tensile strength of 74 MPa. To mitigate the reduction reaction between the PTFE binder and the lithium metal anode, a Li3N‐rich solid electrolyte interphase (SEI) in situ on lithium metal is formed, and the assembled symmetric cell shows excellent cycling stability within 800 h at the current density of 0.2 mA cm−2 and room temperature. Additionally, the ASSLBs using oxidatively stable Li2ZrCl5F in the composite cathode and the prepared solid electrolyte film demonstrate exceptional cycling performance and fast‐charging capability, with a high cell‐level energy density of 354.4 Wh kg−1. The ASSLBs prepared by coupling E‐LPSCl film and stable interface design exhibit excellent electrochemical performance and a high cell‐level energy density. [ABSTRACT FROM AUTHOR]

The presence of polymer material filaments plays a crucial role in the realm of 3D printing. These filaments are utilized in 3D printing to create prototype products efficiently and cost-effectively. However, ensuring the production of high-quality prototype products necessitates the use of superior filaments characterized by consistent diameter and a round cross-section. Filaments are typically manufactured through an extrusion process using either a single screw extruder or a twin extruder. In this research, a DIY single-screw extruder was developed specifically for filament production. The main objective of this study is to generate quality filaments by optimizing the extruder parameters for various polymer materials. Three different polymers; Ethylene-vinyl Acetate (EVA), Polypropylene (PP), and Acrylonitrile Butadiene Styrene (ABS) were employed in this study. The research aimed to assess the melt flow index (MFI) to demonstrate viscous behavior and establish the ideal parameters for each material in the extrusion process. A total of 27 EVA material filament samples, 26 PP filament samples, and 26 ABS filament samples were successfully produced. Through analysis, optimal settings were identified for EVA, PP, and ABS filaments, resulting in high-quality production. The recommended parameters for producing quality EVA filaments included a temperature of 160°C, screw speed of 400 rpm, and take-up speed of 400 rpm. For PP filaments, the optimal settings comprised a temperature of 230°C, screw speed of 700 rpm, and take-up speed of 250 rpm. Lastly, ABS filament production was optimized with a temperature of 210°C, screw speed of 300 rpm, and take-up speed of 100 rpm. This project's outcomes are anticipated to have significant implications for future advancements in filament manufacturing processes. [ABSTRACT FROM AUTHOR]

Tough conductive carbon black/nylon66 (CCB/PA66) antistatic composites modified by maleic anhydridegrafted ethylene-vinyl acetate copolymer (EVA-g-MAH) were prepared by twin-screw extrusion and injection molding. The mechanical, melt flow, and antistatic properties of the composites were tested, and the fracture surface morphologies and crystallization behavior of the composites were observed and studied by scanning electron microscopy (SEM) and differential scanning calorimetry (DSC), respectively. The results showed that EVA-g-MAH has good compatibility with PA66. The antistatic properties of PA66 increased with the addition of CCB, however the toughness and processing ability of the composites decreased significantly. The addition of 10% EVA-g-MAH in the 8% CCB/PA66 blend resulted in a 75.4% and 45.1% increase in impact strength and elongation at break, respectively, while maintaining relatively higher tensile strength (50.5 MPa). When the mass fraction of EVA-g-MAH was 20%, the volume resistivity and surface resistance and of 8% CCB/PA66 decreased by 2 to 3 orders of magnitude to 4.3 x 107 Ω · cm and 6.5 x 106 Ω, respectively, due to the selective location of CCB particles in 8% CCB/EVA-g-MAH/PA66. 10% EVA-g-MAH enhanced the crystal formation of PA66 in the 8% CCB/EVA-g-MAH/PA6 composites, however 20% EVA-g-MAH inhibited the crystal formation of PA66. [ABSTRACT FROM AUTHOR]

Polyolefin elastomer (POE) films can be used as a matrix for ultra‐high molecular weight polyethylene (UHMWPE) fiber‐reinforced composites via a hot‐melt process. However, the low melting temperature of UHMWPE limits composite processing. Therefore, this study aimed to create a film by blending POE with ethylene vinyl acetate (EVA) to reduce the film's processing temperature. Morphological analysis revealed that due to limited compatibility, EVA appeared as droplets within the immiscible POE matrix. T‐Peel tests demonstrated increased self‐adhesion in both the POE/EVA films and the fiber‐reinforced composites with higher EVA content. However, the mechanical properties of POE/EVA films, including tensile properties and shore hardness, were reduced due to EVA having lower inherent properties. UHMWPE fiber‐reinforced composites were fabricated from these films. In composites, optimal tensile and flexural properties were observed at lower EVA content. Scanning electron microscopy analysis suggests that the POE/EVA films are sufficiently infiltrated at 10–20 wt% EVA content. As EVA content increased, the drop weight impact test indicated a reduction in the maximum impact load and an increase in impact energy, attributed to improved adhesion and a broader distribution of impact load across the interface. Highlights: Polyolefin elastomer/ultra‐high molecular weight polyethylene composites' properties were studied with varying ethylene vinyl acetate (EVA) additive content.Add EVA to improve film impregnation when forming compositesIncrease in impregnation affects increase in properties of composites.Characterization shows that the optimal EVA content is 10–20 wt%. [ABSTRACT FROM AUTHOR]

Heat shrink sleeves (HSS) are multilayer polymers that provide corrosion resistance for welding joints of steel pipes. Within the HSS structure, the adhesive layer is a blend of components, such as ethylene vinyl acetate (EVA) and linear low‐density polyethylene (LLDPE). In this study, a systematic approach was employed to investigate the effect of the rheology and blend composition of the maleic anhydride‐modified EVA and maleic anhydride‐modified LLDPE (EVA‐g‐MA/LLDPE‐g‐MA) adhesive layer, prepared by melt processing, on its adhesion properties. Various characterization techniques were employed to investigate the local morphology of the prepared blends at different zones. Peel strength tests were used to characterize the adhesion strength of the prepared adhesives. Our findings demonstrate that the local distribution of EVA‐g‐MA within LLDPE‐g‐MA plays a crucial role in the adhesion strength of the adhesive. The results show that the adhesion strength enhanced by nearly 45% as the composition of EVA‐g‐MA at the surface went up by 20%, shifting the failure location from the epoxy/adhesive interface to the bulk of the adhesive layer. Our hypothesis of the decrease of EVA‐g‐MA intrachain bonding and increase in the EVA‐g‐MA free chain amount in the presence of LLDPE‐g‐MA to improve the adhesion properties was corroborated through our calorimetry results where the relative EVA‐g‐MA crystallinity decreased as LLDPE‐g‐MA was introduced to the blend. The findings of our study highlight the importance of rheological behavior and blend composition in obtaining optimized performance of adhesives within the HSS structure. Highlights: Compression molding of EVA‐g‐MA/LLDPE‐g‐MA induces a layered morphology.Local distribution EVA‐g‐MA/LLDPE‐g‐MA components influence their adhesion.EVA‐g‐MA at the interface improves the adhesion of EVA‐g‐MA/LLDPE‐g‐MA.LLDPE‐g‐MA suppresses the EVA‐g‐MA crystallinity.EVA‐g‐MA/LLDPE‐g‐MA composition affects adhesion at different temperatures. [ABSTRACT FROM AUTHOR]

Fiber-reinforced laminates with flexibility (FRLs) are becoming increasingly crucial across diverse sectors due to their adaptability and outstanding mechanical attributes. Their ability to deliver high performance relative to their weight makes them indispensable in lighter-than-air (LTA) applications, such as aerostats, inflatable antennas, surge bladders, gas storage balloons, life rafts, and other related uses. This research delved into employing woven fabrics as the reinforcement material and explored how their specific parameters, like fiber type, fabric count (warp thread density × weft thread density), fabric areal density, and fabric cover influence the bonding and mechanical properties of laminates. A thorough analysis encompassing standard T-peel (ASTM standard D1876) and a newly proposed yarn pullout in laminate test were conducted on laminates fabricated with various woven reinforcements, each with its unique specifications. The T-peel test was utilized to gauge the adhesive strength between FRL components, offering crucial insights into interfacial bonding within the laminates. Nevertheless, challenges exist with the T-peel test, including instances where the adherents lack the strength to withstand rupture, resulting in unsuccessful peel propagation and numerous outliers that necessitate costly additional trials. Thus, our research group introduced a novel yarn pullout in laminate test to accurately assess adhesion in FRLs. This study uncovered correlations between both adhesion tests (T-peel and yarn pullout in laminate), indicating that the innovative yarn pullout in laminate test could effectively substitute for characterizing adhesion in FRLs. Furthermore, the findings unveiled a complex relationship between woven fabric specifications and laminate properties. We noted that variations in fiber type, yarn linear density, and adhesive type significantly impacted adhesion strength. For instance, Kevlar exhibited markedly superior adhesion compared to Ultra-High Molecular Weight Polyethylene (UHMWPE) when paired with Thermoplastic Polyurethane (TPU) adhesive, whereas UHMWPE demonstrated better adhesion with Ethylene Vinyl Acetate (EVA). Moreover, the adhesion quality lessened as fabric count increased for the same adhesive quantity. These discoveries carry practical implications for material selection and design across industries, from automotive to aerospace, offering avenues to enhance FRL performance. [ABSTRACT FROM AUTHOR]

Photovoltaic (PV) modules are a key technology to aid the imminent transition from carbon‐based energy. End‐of‐life crystalline silicon PV modules produce a waste stream that is predominantly landfilled due to the recycling challenges associated with PV reuse economics. Current practices recycle the aluminum frame and repurpose the junction box but landfill the rest of the module. The primary challenge in recycling the remaining module is finding a technoeconomically viable method for separating the silicon and glass from the ethylene vinyl acetate (EVA) layers. This issue will rapidly expand with time as it is estimated that flat glass production for solar panels is currently unable to meet the demand for PV. Current literature suggests that chemical, thermal, and mechanical delamination offer economically feasible solutions under ideal circumstances. In this work we evaluate these methods using end‐of‐life panels and assess the economic viability. The technoeconomic study presented here suggests the most economically viable option for disposing of end‐of‐life solar panels, given current technology, is landfilling. Thermal delamination may offer an alternative route in the future. Financial incentives, which can be quantified with this work, may be required to kickstart PV recycling to help bridge externalities around environmental impact. [ABSTRACT FROM AUTHOR]

• A pulsed laser method is used to debond ethylenevinylacetate polymer from silicon. • The glass/polymer layer can be separated from silicon in solar photovoltaic cells. • Nanosecond pulses at 355 nm and 532 nm are more effective than 1064 nm. • Transient surface melting does not damage the silicon wafer or metallic contacts. • Pulsed laser debonding can be applied to silicon photovoltaic panel recycling. The active silicon cell of a solar photovoltaic (PV) panel is covered by an ethylenevinylacetate (EVA) adhesive and a protective top glass layer. Separating this glass-EVA layer from the underlying silicon represents a bottleneck for recycling PV panels. Previous work has shown that the EVA-Si bond can be weakened by applying a continuous source of heat to melt the EVA. In this paper, a new method using nanosecond laser pulses is demonstrated to induce transient melting selectively at the EVA-Si interface. This impulsive heating method can cleanly separate the glass-EVA layer from the silicon in both model and commercial multicrystalline PV panels. The dependence of this debonding on parameters like laser pulse fluence (laser pulse energy per area), wavelength, applied pressure, and scan speed were characterized. For model PV panels, the single-pulse laser fluences required for spontaneous separation of the assembly under the force of gravity, were 0.23, 0.32 and 0.78 J/cm2 for 355 nm, 532 nm and 1064 nm, respectively. The use of shorter wavelengths reduces the laser fluence needed for debonding, while higher fluences can compensate for faster laser beam scanning rates. Optical and electron microscopy images of the Si surfaces before and after laser irradiation show that the textured antireflection layer is destroyed but the silver metal grid remains intact. Preliminary experiments using 532 nm pulses showed that the laser debonding method could remove the glass-EVA layer from sections of decommissioned commercial PV panels, even when the top glass layer was densely cracked. [ABSTRACT FROM AUTHOR]

This study focuses on fabricating lattice structural Al 2 O 3 ceramics with lattice infill densities ranging from 25 % to 70 % using filament-based fused deposition modeling (FDM) technology. A specialized filament for FDM printing was developed, comprising 53 vol% Al 2 O 3 powder and ethylene vinyl acetate (EVA) as the primary binder component. The filament demonstrated excellent flexibility as assessed by a self-designed three-point bending test. The impact of lattice infill density and sintering temperature on dimensional changes, microstructure evolution, compressive strength, and strength-to-density ratio was explored. It was found that with increasing sintering temperature, the samples became more compact, resulting in higher levels of shrinkage, bulk density, and compressive strength. At a sintering temperature of 1600 °C, the sintered parts reached their maximum density through the solid-state sintering process. The sample sintered at 1600 °C with 70 % infill density exhibited the maximum compressive strength of 31.47 MPa, with a corresponding strength-to-density ratio of 20.84 MPa/g·cm−3. These findings highlight the successful fabrication of lattice structural Al 2 O 3 with low density and high compressive strength by FDM technology. • Lattice structural Al 2 O 3 ceramics were fabricated by FDM technique. • The filament for FDM with 53 vol% Al 2 O 3 was developed. • Filament demonstrated excellent flexibility. • Sintered lattice structural Al 2 O 3 ceramics at 1600 °C exhibited the maximum compressive strength of 31.47 MPa. [ABSTRACT FROM AUTHOR]

Recently, clothing development 3D printing and the evaluation of its physical characteristics have been explored. However, few studies have tackled thermal comfort, which is a major contributor to the wearers' comfort. Therefore, this study was designed to suggest effective materials and hole sizes for clothing obtained by 3D printing to maintain a comfortable clothing environment. In particular, two main variables, namely five different materials and three-hole sizes, were analyzed. All samples were placed on a hot plate (36 °C), and their surface temperature and humidity were measured for 10 min. The samples with only thermoplastic polyurethane (TPU) achieved the largest temperature change of 3.2~4.8 °C, whereas those with ethylene-vinyl acetate (EVA) foam exhibited the lowest temperature change of −0.1~2.0 °C. Similarly, the samples with only TPU showed the greatest humidity change of −0.7~−5.5%RH. Moreover, the hole size had a larger effect on humidity change than material type. The samples with large holes achieved the largest humidity change of −4.4%RH, whereas the samples without holes had the smallest humidity change of −1.5%RH after 10 min (p < 0.001). Based on these results, various combinations of materials and hole sizes should be considered to fit the purpose of 3D printing clothing. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate microplastic (MP) exposure by Nile tilapia (Oreochromis niloticus) in laboratory conditions. A total of 150 tilapia fishes were equally distributed randomly in 15 different glass tanks with five experimental conditions. Observed results depicted that the presence of MPs in different organs was mainly accumulated from the fish feed rather than externally added MPs in the culture tanks. It was also revealed that the gastrointestinal tract (GIT) was found to be the most susceptible to MPs accumulation followed by gills and muscles in order. However, muscle contained the least size of MPs followed by GITs and gills. A statistical test showed significant correlations among the average length and weight of fish with MP exposure. A filamentous shape was found to be dominant in both GITs and gills while fragment shape was dominant in muscles. FTIR results revealed a total of 12 different polymers in the fish of which two polymers (polyvinyl alcohol and ethylene vinyl acetate) were not detected in the feed-only tanks. Polypropylene (PP) and polyethylene terephthalate (PET) were found to be dominant polymers in all the experimental GIT, gills, and muscle organs. FESEM results indicated the presence of different textures including cracks, edges, flakes, scratches, grooves, and adhering particles. EDX results exhibited the presence of Na, Si, K, Ni, Cu, Zn, As, and Cd in the analyzed samples that may pose additional health risks. Thus, this study could act as baseline data for laboratory-based studies of aquaculture species in future research. [ABSTRACT FROM AUTHOR]

Elastic composites were prepared using a procedure involving hot plates and zinc powder that was directly dispersed into an EVA matrix. The correlation between the zinc content and the conductive properties of the material was studied via impedance spectroscopy, the thermal properties of the material were studied via differential calorimetry and the mechanical properties of the composites were studied via tensile strength curves, representing an important advancement in the characterization of this type of composite material. The composites' tensile strength and elongation at break decrease with the addition of filler since zinc particles act as stress-concentrating centres, while the composites' hardness and Young's modulus increase because of an increase in the stiffness of the material. The AC perturbation across the EVA/Zn composites was characterized using an RC parallel equivalent circuit that allowed us to easily measure their resistivity ( ρ p ) and permittivity ( ε p ). The dependence of these electrical magnitudes on the zinc content is correlated with their mechanical properties across the characteristic time constant τ p =   ρ p · ε p of this equivalent circuit. The dependence of the mechanical and electrical magnitudes on the zinc content is consistent with the formation of percolation clusters. The addition of graphite particles increases their potential performance. Three possible mechanisms for the electrical transport of the ac-perturbation across the EVA/Zn composites have been identified. Chemical corrosion in acid media causes the loss of zinc surface particles, but their bulk physical properties practically remain constant. [ABSTRACT FROM AUTHOR]

This research study analyzes the influence of Ethylene-Vinyl Acetate (EVA) resin on the properties of Polybutylene Terephthalate (PBT)/EVA blends produced by injection molding technique. It is based on the fact that a way to recycle PBT from toothbrush bristles is needed. Mechanical samples were made by mixing EVA into PBT with 0, 5, 10, 15, 20, and 25% contents. The samples were tested for flexural strength, impact strength, and hardness according to the standards of ASTM D790, ASTM D256, and ASTM D2240, respectively. The results show that when increasing the EVA content in the PBT/EVA blends, the flexural strength tends to decrease; the hardness fluctuates along a decreasing trend; however, the decrease is not significant. Interestingly, the measured impact resistance results are very positive, especially at the highest increase point, increasing by 40.7% compared to neat PBT. The microstructure results showed a good dispersion of EVA on the PBT substrate, but there was no compatibility between these two polymers. The results of XRD analysis showed that when EVA was mixed, it increased the crystallinity and improved the crystal growth of the blends. [ABSTRACT FROM AUTHOR]

We demonstrate the realization of reliable, high-quality, micro-sized graphene-based field-effect devices on a flexible and transparent substrate, ethylene vinyl acetate (EVA)/polyethylene terephthalate (PET), using a convenient hot-press lamination transfer and employing parylene-N as a dielectric material for gating. Using this technique, we fabricate a graphene thermocouple on the EVA/PET substrate. Specifically, the graphene is patterned in a U-shape, and its legs are equipped with two independent top gates. Full control of the carrier density and type by electrostatic gating in the two graphene regions allow the formation of a thermocouple layout, exhibiting an enlarged thermovoltage signal when the two regions are doped with opposite types of carriers and leading to a maximum sensitivity with a thermopower of ∼73 µV/K. This agrees well with the working principle of thermocouple, and it proves the good compatibility and functionality of the graphene thermocouple on the EVA/PET substrate. Our findings suggest possible applications for producing scalable and reliable graphene-based electronic devices on flexible and transparent substrates in a simple way. [ABSTRACT FROM AUTHOR]

Background/Aim: The interaction between the ethylene‐vinyl acetate (EVA) with distinct materials utilized for obtaining dental models can affect the performance of resulting mouthguards. This study attempted to evaluate the effect of different materials for conventional (dental stone) or 3D‐printed (resin) models on EVA's physical and mechanical properties and surface characteristics. Material and Methods: EVA sheets (Bioart) were laminated over four model types: GIV, conventional Type IV dental stone model (Zhermak); ReG, resin‐reinforced Type IV dental stone model (Zero Stone); 3DnT, 3D resin printed model (Anycubic) without surface treatment; 3DT, 3D‐printed model (Anycubic) with water‐soluble gel (KY Jelly Lubricant, Johnson & Johnson) coating during post‐curing process. The EVA specimens were cut following the ISO 37‐II standard (n = 30). Shore A hardness was measured before and after plasticization on the contact (internal) or opposite (external) surfaces with the model. The breaking force (F, N), elongation (EL, mm), and ultimate tensile strength (UTS, MPa) were measured using a universal testing machine. Macro‐photography and scanning electron microscopy were adopted for classifying the EVA surface alteration. Data were analyzed by one‐way ANOVA with repeated measures, followed by Tukey's test (α =.05). Results: Plasticization significantly decreased Shore A values for the tested EVA regardless of the model type (p <.001). Higher F, El, and UTS values were verified for the EVA with 3DT and GIV models compared to ReG and 3DnT (p <.001). 3DnT models resulted in severe surface alteration and a greater reduction of the mechanical properties of the EVA. Conclusion: The interaction of EVA with 3D resin‐printed models without surface treatment or resin‐reinforced Type IV dental stone models significantly affected the physical and mechanical properties of this material. The utilization of water‐soluble gel coating during the post‐curing process of 3D resin printed models improved the mechanical properties of the EVA, similarly when this material was plasticized over conventional Type IV dental stone model. [ABSTRACT FROM AUTHOR]

Ethylene vinyl acetate (EVA) foam is widely used as midsole material in athletic footwear due to its lightweight and cushioning properties. However, EVA foam suffers from low mechanical strength, abrasion resistance, and fatigue resistance. Reinforcing EVA foam with graphene nanoplatelets is a promising approach to improving its mechanical performance for footwear applications. This study investigated the effect of 0.1–1 wt% graphene nanoplatelets on the properties of EVA foam composites relevant to midsole performance. The results showed that 0.1–0.2 wt% graphene provided optimal reinforcement, exhibiting 33–40% higher impact energy absorption, 50–60% lower compressive stiffness, 30% higher flexural stiffness, and up to 40% lower abrasion volume loss. Under simulated use conditions, the composites demonstrated higher energy return and fatigue resistance. The graphene nanoplatelets acted as effective reinforcements within the EVA foam by improving stress transfer, inhibiting crack propagation, and shielding the foam surface. The findings indicate that reinforcing EVA foam with small amounts of graphene nanoplatelets can develop midsole materials with enhanced mechanical performance for athletic footwear. [ABSTRACT FROM AUTHOR]

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The unregulated metallic deposition and continuous cracking of the fragile solid electrolyte interphase are considered the critical barriers that compromise the cyclability of lithium metal batteries (LMB), especially under low N/P ratio (<3) pairing modes. Herein, an ultra‐thin (5 µm), lightweight (0.25 mg cm−2), and moisture‐proof interfacial layer composed of the high‐entropy alloys (denoted as HEAs) and interweaved carbon nanotubes (CNTs) scaffold is constructed to modify the current collector, moreover, the thermally‐induced Li22Si5 alloy blended with the hydrophobic ethylene‐vinyl acetate copolymer (EVA) is infiltrated into the scaffold pores as the moisture‐proof cation reservoir. The HEA@CNT/Li22Si5@EVA interfacial layer not only maximizes the Li‐utilization degree with minimal voltage divergence in symmetric cells but also compensates for irreversible Li depletion in the pouch‐format anode‐less models. As the HEA@CNT/Li22Si5@EVA‐Cu substrate paired with the LiNi0.8Mn0.1Co0.1O2 cathode in a 200 mAh prototype, the phase evolution of oxide cathode and efficient Li utilization at the anode substrate can be real‐time monitored by the transmission‐mode operando X‐ray diffraction. This interfacial layer strategy affords multifunctionality to enable the LMB prototyping without excessive Li abuse. Consequently, cycling endurance and the balanced energy densities (420.1 Wh kg−1) are obtained on the whole cell. [ABSTRACT FROM AUTHOR]

The degradation behaviors of the encapsulant and the imbedded additives significantly determine the reliability of solar modules. Nevertheless, a link between the degradation of the encapsulant, including the additive interactions, and the longevity of the overall module is rarely established until now. Herein, mini‐modules containing ethylene‐vinyl acetate copolymer (EVA) as encapsulant are subject to damp heat (DH) or ultraviolet (UV) weathering based on IEC 61215. Macroscopically, the degradation under both weathering types characterized by I–V measurements and electroluminescence (EL) measurements is diverging in dependence on the used stressor. Using electron paramagnetic resonance and orbitrap mass spectrometry, it is shown that deacetylation of the EVA occurs significantly for both types of weathering. In the case of DH, however, the mechanism of action of the UV stabilizer is hindered, so that strong encapsulant degradation is observed despite a lower energy input in comparison with UV. Furthermore, the produced acetic acid under DH weathering leads to the observed reduction in EL, an increase in series resistance, and, a reduction of the performance of the modules. The work carried out shows that the degradation of the solar modules is strongly dependent on the behavior of the UV stabilizer. [ABSTRACT FROM AUTHOR]

The type of matrix resin of the semi‐conductive shielding layer directly affects the thermal aging characteristics of the semi‐conductive shielding layer and the high‐voltage cable. In this paper, ethylene vinyl acetate (EVA), ethylene ethyl acrylate (EEA), and ethylene butyl acrylate (EBA) resins were used as matrix to prepare carbon black (CB) + EVA, CB + EEA, and CB + EBA shielding materials. The law of physicochemical, electrical, and mechanical properties of different matrix resin shielding materials with aging time was studied, and the influence mechanism of matrix resin on the aging characteristics of shielding materials was analyzed. The results show: with the increase of aging time, the crystallization area and the number of functional groups of the three shielding materials decreased to varying degrees. The number of functional groups in CB + EBA shielding materials decreased evenly with aging time, but that of CB + EVA and CB + EEA shielding materials changed significantly after 7 days of aging. After 60 days of aging, the crystallization area of CB + EBA shielding material changed slightly, but that of CB + EVA and CB + EEA shielding material decrease significantly. The electrical properties of the three shielding materials showed different decreasing trend with aging time. When the aging time is 7 days, the positive temperature coefficient (PTC) effect of CB + EEA shielding material decreases obviously. When the aging time is 30 days, the resistivity of CB + EVA and CB + EEA shielding material increases slowly (9 Ω cm–12 Ω cm) with the increase of temperature. When the aging time is 60 days, the resistivity of CB + EBA shielding material decreases obviously, and the PTC effect weakens obviously. Taking the mechanical properties of the shielding material as reference, the rapid deterioration stage of the mechanical properties of the three shielding materials is different. The CB + EVA and CB + EEA shielding material rapid deterioration time is 0–7 days, and the tensile strength and elongation of the shielding material are greatly reduced. The rapid deterioration stage of CB + EBA shielding material is 7–30 days, and the tensile strength and elongation decrease from 24.38 MPa and 499.5% to 14 MPa and 155.7%, respectively. This work can provide data support for the selection of matrix resin of shielding material and the fault analysis of shielding layer of high voltage cable. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries utilizing sulfide solid electrolytes hold considerable potential for achieving both high energy density and enhanced safety. However, the substantial volume changes experienced by sulfur during cycling result in mechanical stress accumulation, leading to mechanical degradation and thereby degrading overall electrochemical performance. In this study, a stress‐buffer strategy is proposed to address this challenge by engineering a mechanically resilient crosslinked structure for the composite sulfur cathode. This structure is accomplished through the integration of a highly flexible thermoplastic elastomer (ethylene vinyl acetate, EVA), which enables stress release during sulfur volume variations by the repeated stretching and shrinking of EVA, thereby maintaining stable ionic/electronic diffusion channels within the electrode. By virtue of the mechanically stable architecture, the stress evolution experienced by the entire sulfur electrode is substantially reduced, witnessing a remarkable decrease of ≈33.7%. Consequently, the S‐EVA composite cathode demonstrates exceptional electrochemical performance, especially cycling stability. Notably, the S‐EVA composite cathode, with a high loading of 7.5 mg cm−2, exhibits stable cycling performance close to 3.0 mAh cm−2 within 50 cycles. This work not only offers novel insights into mitigating the mechanical stress within the electrode but also paves the way for developing durable high‐performance all‐solid‐state batteries. [ABSTRACT FROM AUTHOR]

Introduction: The choice of materials for covering plantar orthoses or wearable insoles is often based on their hardness, breathability, and moisture absorption capacity, although more due to professional preference than clear scientific criteria. An analysis of the thermal response to the use of these materials would provide information about their behavior; hence, the objective of this study was to assess the temperature of three lining materials with different characteristics. Materials and Methods: The temperature of three materials for covering plantar orthoses was analyzed in a sample of 36 subjects (15 men and 21 women, aged 24.6 ± 8.2 years, mass 67.1 ± 13.6 kg, and height 1.7 ± 0.09 m). Temperature was measured before and after 3 h of use in clinical activities, using a polyethylene foam copolymer (PE), ethylene vinyl acetate (EVA), and PE-EVA copolymer foam insole with the use of a FLIR E60BX thermal camera. Results: In the PE copolymer (material 1), temperature increases between 1.07 and 1.85 °C were found after activity, with these differences being statistically significant in all regions of interest (p < 0.001), except for the first toe (0.36 °C, p = 0.170). In the EVA foam (material 2) and the expansive foam of the PE-EVA copolymer (material 3), the temperatures were also significantly higher in all analyzed areas (p < 0.001), ranging between 1.49 and 2.73 °C for EVA and 0.58 and 2.16 °C for PE-EVA. The PE copolymer experienced lower overall overheating, and the area of the fifth metatarsal head underwent the greatest temperature increase, regardless of the material analyzed. Conclusions: PE foam lining materials, with lower density or an open-cell structure, would be preferred for controlling temperature rise in the lining/footbed interface and providing better thermal comfort for users. The area of the first toe was found to be the least overheated, while the fifth metatarsal head increased the most in temperature. This should be considered in the design of new wearables to avoid excessive temperatures due to the lining materials. [ABSTRACT FROM AUTHOR]

The study focusses on a low‐density polyethylene/isotactic polybutene‐1 peel system with low‐density polyethylene as matrix and isotactic polybutene‐1 as peel component sealed against itself (cohesive peel system), and on an ethylene vinyl acetate/linear low‐density polyethylene peel system with ethylene vinyl acetate as matrix and linear low‐density polyethylene as peel component sealed against polyethylene terephthalate (adhesive peel system). Due to a new approach to estimate the true fracture surface using 3D reconstruction, it was possible to determine the true adhesive energy release rate, especially for cohesive peel systems. This enables a direct comparison of the fracture mechanics parameters determined from both types of peel systems. The results reveal that the recipe has a distinct influence on the peel behavior. An increasing amount of the used peel component leads in any case to a decrease of the peel force as well as of the energy release rate for both, sealed adhesive and cohesive peel systems. Using application engineering examples generalizable relationships between structure and properties of peel systems could be estimated and the structure sensitivity of the fracture mechanical parameters could be proven. [ABSTRACT FROM AUTHOR]

In this work, self-reinforced composite of recycled polyester (rPET) fibers/recycled poly (ethylene terephthalateco-1,4-cylclohexy-lenedimethylene terephthalate) (rPETG) was prepared by internal mixing and molding press, in which rPET fibers were modified according to the previous method. The effects of compatibilizers including polyethylene-octene grafting glycidyl methacrylate (POE-g-GMA) and ethylene vinyl acetate grafting maleic anhydride (EVA-g-MAH) on the toughness of the composites were studied, respectively. The results showed that POE-g-GMA had better toughening effect on composite than EVA-g-MAH, the POE-g-GMA not only increased the toughness of rPET fibers/rPETG composite but also maintained the strength of composite at a high level. The impact strength of modified rPET fibers/POE-g-GMA/rPETG composite was found to increase by 910%. And, the bending strength and tensile strength were improved by 34.7% and 22.2%, respectively. DSC and SEM results indicated that with an increase in POE-g-GMA content, the degree of crystallinity of rPET fibers/POE-g-GMA/rPETG decreased, bonding between the fibers and matrix became tight, which improved the stress transfer ability between the matrix and the fibers. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to investigate the performance of bio-based lubricants (BBL), namely, palm mid-olein (PMO) enriched with an antioxidant agent, tertiary-butylhydroquinone (TBHQ) and a viscosity improver, ethylene-vinyl acetate (EVA), in journal bearing (JB) applications. Design/methodology/approach: Samples of the BBL were prepared by blending it with TBHQ and EVA at various blending ratios. The oxidative stability (OS) and viscosity of the BBL samples were examined using differential scanning calorimetry and a viscometer, respectively. Meanwhile, their performance in JB applications was evaluated through the use of a JB test rig with a 0.5 length-to-diameter ratio at various operating conditions. Findings: It was found that the combination of PMO + TBHQ + EVA demonstrated a superior oil film pressure and load-carrying capacity, resulting in a reduced friction coefficient and a smaller attitude angle compared to the use of only PMO or VG68. However, it was observed that the addition of TBHQ and EVA to the PMO did not have a significant impact on the minimum oil film thickness. Practical implications: The results would be quite useful for researchers generally and designers of bearings in particular. Originality/value: This study used PMO as the base stock, and its compatibility with TBHQ and EVA was investigated in terms of its OS and viscosity. The performance of this treated BBL was evaluated in a hydrodynamic JB. Peer review: The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2023-0363/ [ABSTRACT FROM AUTHOR]

There is a growing need for a mouthguard sheet material with higher shock absorption and dispersion capacity than those obtained by conventional materials. A five-layer mouthguard sheet material was previously developed using laminated ethylene vinyl acetate and polyolefin copolymer resin. In this study, the shock absorption capacity and dispersion capability of the new sheet material were investigated and compared with those of other materials. Impact testing for the new sheet material showed that the force required to displace the sheet by 1 mm was significantly higher at all thicknesses (p<0.001), whereas the puncture energy and displacement were significantly lower than those for ethylene vinyl acetate (p<0.05). The five-layer mouthguard sheet material successfully absorbed and resisted shock. Therefore, the sheet material potentially increases resistance to applied deformation in teeth and alveolar bone and maintains structure. The five-layer sheet material could expand the range of mouthguard products and help prevent oral trauma. [ABSTRACT FROM AUTHOR]

Electromagnetic shielding plastics with different mass fractions were prepared by melt blending three kinds of silver-coated copper powder (Ag@Cu) with ethylene-vinyl acetate copolymer (EVA). The effects of different mass fractions and particle sizes of Ag@Cu on the electrical conductivity, shielding properties and mechanical properties of EVA-based electromagnetic shielding plastics were investigated. EVA-based electromagnetic shielding plastics were toughened by maleic anhydride grafted ethylene-octene copolymer/ethylene-octene copolymer (POE-g-MAH/POE) toughening masterbatch and polyisobutylene (PIB)/terpene toughening masterbatch, respectively, to obtain highly filled electromagnetic shielding plastics. The results show that with the increase of Ag@Cu content, the electrical conductivity of EVA-based electromagnetic shielding plastics increases, while the mechanical properties decrease. The percolation threshold of the composites decreases with the increase of filler particle size. When the Ag@Cu filling content is 80%, the shielding effectiveness increases with the increase of filling particle size. Compared with POE-g-MAH/POE, the toughening effect of PIB/terpene is the best, the elongation at break is increased to 187.3%, the shielding effectiveness is kept above 70 dB in the range of 30~1 000 MHz, and it shows better extrusion processability. [ABSTRACT FROM AUTHOR]

This paper proposes a novel design for a frequency reconfigurable and bandwidth-enhanced antenna for use in biomedical telemetry applications. Data pertaining to a patient’s body parameters, such as blood pressure, pulse, and temperature, are gathered using sensors and then transmitted to a remote place for monitoring. The proposed antenna is connected to a wearable transmitter, which transfers the body parameter data to a centrally located nearby control unit. The antenna operates in the 5.8 GHz band in single-band mode and in the 4.27 GHz (C band) and 5.8 GHz industrial, scientific, and medical (ISM) bands in dual-band mode. The use of ethylene-vinyl acetate foam as a substrate makes the structure waterproof and ultraviolet resistant. The basic antenna structure equipped with proximity coupling offers a front-to-back ratio (FBR) of 17.62 dB and a bandwidth of 122 MHz. With an additional upper patch and resonant slots, bandwidth enhancement of 82.85% and 11.57% improvement in the FBR are achieved, respectively. Overall, a maximum FBR of 19.66 dB and gain of 5.0 dBi are attained over the resonant frequency. The specific absorption rate is found to be 0.145 W/kg for 10 gram of tissue. [ABSTRACT FROM AUTHOR]

Potential‐induced degradation (PID) may be a serious concern in photovoltaic (PV) modules and plants, particularly when approaching high system voltages (1500+ V). Here, we investigate PID occurring in bifacial rear‐emitter silicon heterojunction (SHJ) solar cells encapsulated in a glass/glass (G/G) module configuration with ethylene vinyl acetate (EVA) as an encapsulant. PID testing was performed at 85°C in 85% relative humidity (RH), and the solar cells were subjected to −1 kV and +1 kV for up to 800 h. SHJ cells were found to degrade when subjected to −1 kV, and to a lesser extent when left unbiased in damp heat (DH) conditions, while the application of +1 kV prevented degradation. Although prone to PID after extended test durations, the SHJ mini‐modules investigated in this study noticeably passed the industry standard (IEC 61215:2021) PID test of 96 h. The degradation was primarily characterized by losses in short‐circuit current (ISC) at the front side, followed by fill factor (FF) and open‐circuit voltage (VOC). A cross‐sectional transmission electronic microscopy analysis of the laminates subjected to −1 kV highlighted a transport of sodium (Na) through the transparent conductive oxide (TCO), reaching the amorphous Si/TCO interface. The samples tested in DH conditions and with positive PID test conditions did not exhibit such a migration of Na. To account for these observations, we updated a previously proposed model describing the sensitivity of SHJ cells to water. In our degradation model, moisture in the module corrodes the glass, creating sodium hydroxide (NaOH) that then percolate through the EVA before reaching the SHJ cell. The application of a high negative bias amplifies the previous mechanism by increasing the availability of Na+ and also enhances the drift of Na+ through the EVA to the cell. Finally, we demonstrate that PID can be mitigated or suppressed at the module level by using a high‐volume resistivity encapsulant with a low water vapor transmission rate (WVTR) or by encapsulating SHJ solar cells in a configuration impermeable to water (e.g., using an edge sealant). [ABSTRACT FROM AUTHOR]

Ethylene vinyl acetate (EVA) copolymers are widely employed as pour point depressants to enhance the flow properties of crude oil. However, EVA copolymers have limitations that necessitate their development. This work investigated the modification of EVA via gamma radiation-induced grafting of butyl acrylate (BuA) monomers and the evaluation of grafted EVA as a pour point depressant for crude oil. The successful grafting of poly(butyl acrylate) p(BuA) onto EVA was verified through grafting parameters, FTIR spectroscopy, and 1H NMR spectroscopy. Treating crude oil with 3000 ppm of (EVA)0kGy, (EVA)50kGy, and (1EVA:3BuA)50kGy yielded substantial reductions in pour point of 24, 21, and 21 °C, respectively. Also, rheological characterization demonstrated improving evidenced by a viscosity reduction of 76.20%, 67.70%, and 71.94% at 25 °C, and 83.16%, 74.98%, and 81.53% at 12 °C. At low dosages of 1000 ppm, the EVA-g-p(BuA) exhibited superior pour point reductions compared to unmodified EVA, highlighting the benefit of incorporating p(BuA) side chains. The grafted EVA copolymers with p(BuA) side chains showed excellent potential as crude oil flow improvers by promoting more effective adsorption and co-crystallization with paraffin wax molecules. [ABSTRACT FROM AUTHOR]

In this study, the miscibility of ethylene vinyl acetate/olefin block copolymer (EVA/OBC) blends was investigated through the determination of melt-state viscoelastic properties as well as by morphological analysis using experimental and theoretical approaches. The SEM micrographs showed droplet-matrix morphology, and the blend containing a higher content of OBC exhibited the highest OBC-dispersed phase domain size. The complex viscosity of EVA/OBC blends showed a positive deviation from the log-additivity rule at all compositions, which indicates the strong interaction between phases. Cole–Cole and Han plots indicated miscibility in the molten state between EVA and OBC. The interfacial tension of EVA/OBC blends was determined by the implementation of Palierne and Bousmina emulsion models. Moreover, the blend samples were characterized in terms of creep properties using a dynamic mechanical analyzer, which demonstrated that the OBC increased the creep strains of the blends. The four-element Burger model and the Findley power law model were employed to model the creep behaviors of the EVA, OBC, and blend samples. The model predictions indicated that the incorporation of OBC into the EVA improved the creep rate of EVA/OBC blends significantly. [ABSTRACT FROM AUTHOR]