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Carbon fiber reinforced epoxy resin matrix composite is one of the most important composite materials in the world. Many researchers have conducted a lot of research on epoxy resin matrix systems in recent years, mainly to improve the problem with the short curing time of the matrix system and epoxy resin's high viscosity. The final aim is to enhance various aspects of composites' performance and optimize the production process. A new type of water dispersed epoxy resin matrix system is investigated in this paper and the target is to optimize the mechanical, thermal, and electrical performances of the composites with the water dispersed epoxy resin matrix by varying different doping particles and different resin/catalyst ratios. Through a series of experiments, it is evident that varying the ratio of resin to catalyst in the matrix system will not significantly improve the mechanical as well as thermal properties of the composites. However, increasing the amount of catalyst in the matrix system can greatly improve the electrical properties of its composite samples. In addition to this, the addition of doping particles to the matrix systems has the effect of slightly enhancing the tensile modulus, thermal conductivity, and electrical conductivity of their composites. Highlights: A new water‐dispersed epoxy resin matrix system improves processing technology.Increasing amount of catalyst in the matrix system improves electrical resistivity.Adding particles to matrix systems has a slight effect on different properties. [ABSTRACT FROM AUTHOR]

Nylon nanocomposites were prepared by in‐situ ring‐opening polymerization to overcome the problem of poor properties due to the uneven dispersion of the nanoparticles by the traditional melt blending. This high‐performance polyamide 6 (PA6) nanocomposites with high dispersion and strong interface was prepared by grafting PA6 onto the surface of cellulose nanocrystals (CNC). The micromorphology, mechanical, crystalline and thermal properties of the composites were also investigated. Firstly, the hydroxyl group on the surface of CNC reacted with the para isocyanate of toluene diisocyanate (TDI), and the remaining ortho isocyanate was blocked by caprolactam to prepare CNC grafted with caprolactam (CNC‐g‐CL). Then CNC‐g‐CL was used as an activator to prepare cellulose nanocrystal grafted with polyamide 6 (CNC‐g‐PA6) composites by the ring‐opening polymerization of caprolactam on the CNC. The effects of different reaction temperatures, solvent amounts and molar ratios on the grafting rate of CNC‐g‐CL were investigated. The results showed that the highest grafting rate of CNC‐g‐CL with 66.7% was achieved at a reaction temperature of 45°C, 0.1 g/mL CNC in toluene, and a molar ratio of 6 for TDI/CNC. Further, different CNC‐g‐PA6 composites prepared from different CNC content and activator content were explored. For CNC‐g‐PA6 composites, CNC was uniformly dispersed in the PA6 matrix and had a good compatibility with the matrix. CNC exhibited significant reinforcement in the composites with a tensile strength of up to 108 MPa. In addition, the glass transition temperature of CNC‐g‐PA6 was increased to 92°C, which significantly improved the heat resistance of the new composites. Highlights: Effects of reaction condition of CNC and TDI on DSTDI and DSCL were studied.Effects of CNC and activator content on CNC‐g‐PA6 properties were studied.CNC is uniformly dispersed in PA6 with average particle size less than 1 micron.The nylon matrix was significantly strengthened by the addition of CNC.The addition of CNC significantly improved the heat resistance of the composites. [ABSTRACT FROM AUTHOR]

The development of innovative composite materials through the amalgamation of thermoplastic polyurethane (TPU) with bismuth sodium titanate (BNT) and carbon nanotube (CNT) fillers was investigated. Before the composite fabrication, the fillers' surfaces were treated to enhance their compatibility with the TPU matrix. Hybrid fillers of BNT and CNTs were fabricated by mixing the two types of filler particles through ball milling and subsequently annealing the mixture at 250°C. Melt‐blending and injection molding were utilized to synthesize the composites at 210°C processing temperature. The prepared composites showed significantly enhanced thermal conductivity, dielectric constant, thermal stability, and thermomechanical properties compared with the neat TPU matrix. For instance, the dielectric constant was enhanced by 340% upon the inclusion of 40 wt.% BNT and CNT fillers compared to the neat TPU matrix (40CBNT‐TPU has 13.2). In particular, the inclusion of BNT‐CNT particles in the TPU matrix improved the thermal conductivity of the TPU matrix by 1180% tremendously as compared to neat TPU (40CBNT‐TPU has 2.6 W/(m.K)). Highlights: Crystalline bismuth sodium titanate (BNT) is fabricated.Degradation of 8 wt.% of the IPDI‐treated BNT proves surface treatment.Dielectric constant (DC) improved by 340% compared to neat TPU.Thermal conductivity (TC) enhanced 11.4 times compared to neat TPU.Improvement in TC and DC will make it applicable in electronic materials. [ABSTRACT FROM AUTHOR]

The matrix cracking of carbon fiber reinforced epoxy resin based composites (CFRPs) at cryogenics (such as liquid nitrogen temperature) is a major issue affecting the normal operation of deep space and deep‐sea detectors, as microcracks caused by the thermal residual stress of both can reduce the structural integrity of the devices. In this work, we report an epoxy (EP) nanofiller CuO nanorods (CuO NRs) with negative thermal expansion properties at cryogenics. Experiments showed that CuO NRs can effectively inhibit the shrinkage of EP at cryogenics and improve the mechanical properties of EP at cryogenics. A temperature dependent prediction model for the tensile strength of EP/CuO NRs was proposed, and the predicted results were in good agreement with experimental results. Finally, through a combination of experiments and theory, it was demonstrated that the tensile strength of EP/CuO NRs at cryogenics is jointly enhanced by the enhancement effect of the nanomaterials and the axial compressive thermal residual stress between EP and CuO NRs. Highlights: Successfully prepared CuO nanorods with negative expansion properties at low temperatures, and found that they can effectively inhibit the shrinkage of epoxy resin at cryogenics.At cryogenics, the expansion of CuO nanorods enhances their interface effect with epoxy resin and improves the tensile strength of epoxy resin composites.The theory of tensile strength of epoxy resin at cryogenics was proposed for the first time. Theoretical analysis shows that the low temperature residual thermal stress between CuO nanorods and epoxy resin is the main factor to improve its tensile strength. [ABSTRACT FROM AUTHOR]

Poor interfacial adhesion between carbon fibers (CF) and the resin matrix has been a limiting factor in advancing the properties of composites. To address this challenge, this study employs the sizing method to coat carbon nanotubes (CNTs) and hexagonal boron nitride nanosheets (h‐BN) onto the CF surface. The 3D structures formed by strategic of combination 1D and 2D nanomaterials, markedly enhances the mechanical, thermal and frictional properties of CF composites. The results reveal a significant boost in the flexural strength, flexural modulus, interlaminar shear strength and interfacial shear strength of the prepared CF composites, registering increases of 53.96%, 60.41%, 55.58% and 55.35%, respectively. These advancements stem from the heightened surface reactivity and roughness of the fibers, facilitated by the synergistic interactions between CNTs and BN. Furthermore, the thermal conductivity of the composites exhibits a remarkable increase of 63.56%, attributed to the synergistic coupling between CF and BN, establishing an efficient thermal conductivity pathway within the composites. This research provides a highly effective approach for crafting high‐performance CF composites. Highlights: Construction of 3D network structures on CF surfaces by the sizing method.Synergistic coupling between BN and CNT enhances composite properties.Synergistic enhancement of friction and thermal properties of CF composites. [ABSTRACT FROM AUTHOR]

The high‐performance PPS/PEEK blends/composites were prepared with different mass ratios using polyphenylene sulphide (Solvey, Ryton®‐R‐4‐230 NA) and polyetherether ketone (Victrex, PEEK450 GL 30). All the blend samples had a single Tg, which revealed good compatibility between PPS and PEEK. The Tm was increased from 279.6 to 339.9°C due to addition of PEEK into PPS. Also, addition of PEEK into the blend increased the impact and tensile strength of the PPS material. The impact strength of the blend, PPS/PEEK (20/80) exhibited the maximum value of 113.64 J/m which was higher than that of PPS (70.66 J/m). The tensile strength of the blend was increased continuously with increasing the content of PEEK from 20 to 80 wt. % and reached the maximum value of 160.64 MPa. Additionally, milled carbon fiber (MCF) was also incorporated in order to obtain high strength PPS/PEEK blends/composites with good dielectric property. The dielectric performance of the composites was observed to increase with MCF content (in the frequency range 5.8 to 18 GHz). Highlights: This investigation relates to high‐performance PPS/PEEK blends and composites.Incorporation of milled carbon fiber resulted promising dielectric properties.Such composites may have Advanced structural EMI shielding electronics and/or aerospace applications. [ABSTRACT FROM AUTHOR]

Three‐dimensional molybdenum disulfide (MoS2) functionalized MWCNTs hybrid nanoparticles were synthesized using in‐situ hydrothermal reaction. Two types of hybrids, MoS2/MWCNTs‐1 and MoS2/MWCNTs‐2 with MWCNTs to MoS2 precursor weight ratios 1:2 and 1:1 respectively were prepared with varying degrees of hybridization and the effects of their incorporation on tensile strength and fracture toughness properties of epoxies were investigated. Epoxy/MoS2/MWCNTs‐2 nanocomposites showed exceptional mechanical properties due to their improved dispersion, constrained chain mobility and excellent interfacial interactions. MoS2/MWCNTs‐2 nanocomposites showed maximum improvement of tensile strength by 28.52% at 0.5 wt% nanofiller concentration and the highest improvements in fracture toughness by 172% at 0.2 wt% nanofiller concentration. The excellent enhancement of fracture toughness properties was due to the synergic effect of MoS2/MWCNTs hybrid nanoparticles due to the crack pinning and bifurcation properties of MoS2 nanoparticles along with the pull‐out and crack bridging mechanisms of MWCNTs as observed in morphological analysis of fractures nanocomposites. The incorporation of 0.2 wt% of MoS2/MWCNTs‐2 increased the degradation temperatures of epoxy from 591 to 796°C at 95% weight loss due to the improved physical barrier effect. Highlights: MoS2/MWCNTs nanoparticles were synthesized using in‐situ hydrothermal reaction0.5 wt% MoS2/MWCNTs‐2 incorporated epoxies showed highest tensile strength0.2 wt% MoS2/MWCNTs‐2 incorporated epoxy composites show improved K1c valueIncorporation of MoS2/MWCNTs improved the thermal stability of epoxySynergistic effect of nanocomposite due to crack pinning, bifurcation & bridging [ABSTRACT FROM AUTHOR]

Fluorine rubber (FKM) stands as a pivotal sealing material extensively employed in aerospace and nuclear industries. However, its efficacy will be seriously affected by ionizing radiation. Enhancing its radiation resistance becomes imperative to uphold the stability and safety of associated equipment. This study introduced hexagonal boron nitride (h‐BN) into the FKM as radioprotective fillers through mechanical blending. The interfacial interaction between matrix and h‐BN, the mechanical performances, thermal properties, and radiation stability of composites were systematically examined. Noteworthy findings highlight the presence of robust interaction forces between h‐BN and the matrix, leading to increased crosslink density and improved mechanical properties. The tensile strength of composite with 10 phr fillers (BN/FKM‐10) increased by 30% compared to that of pure FKM. Simultaneously, the introduction of h‐BN greatly enhanced thermal conductivity and radiation stability. The absorbed dose required to achieve a 50% reduction in elongation at break of BN/FKM‐10 surpassed that of FKM by 1.69 times. These results underscore the potential of incorporating h‐BN to simultaneously enhance the mechanical performance, thermal property, and radiation resistance of fluorine rubber. Highlights: The chemical interaction force between h‐BN and FKM was confirmed.FKM composites tensile strength was enhanced by h‐BN as an additive crosslinker.The incorporation of h‐BN improves FKM composites thermal conductivity.The radiation resistance of FKM composites has been improved with h‐BN. [ABSTRACT FROM AUTHOR]

Organic–inorganic composites have attracted great interest, due to their remarkable impact, causing improvements in the mechanical properties of polymers when compared with their pure forms. Hence, this study has been attempted to investigate and compare the various properties of high‐density polyethylene (HDPE), separately doped with two different types of clay minerals using melt‐mixing and compression‐molding techniques. The fourier transform infrared spectroscopy (FT‐IR), x‐ray diffraction (XRD), and scanning electron microscope (SEM) were used to characterize the structural and morphological properties of the resulting composites, while, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were employed to characterize their thermal properties. Morphological investigations indicated homogeneous dispersion of both clay materials in the HDPE matrix. Moreover, an investigation was conducted on the mechanical properties of composites, including elastic modulus, yield stress, tensile strain at break, tensile strain at yield, tensile stress at break, and ultimate tensile strength. According to the mechanical data, adding 6.0 wt% of bentonite or dolomite to HDPE led to an increase in the elastic modulus up to 125% and 116% increments, respectively. An increase in the filler content in the composite from 2.0 to 8.0 wt% resulted in a slight decrease in tensile stress at break, yield stress, tensile strain at break, and tensile strain at yield. [ABSTRACT FROM AUTHOR]

Laminated polymer composites are widely used in ballistic barriers where polyethylene can be applied. The mechanical properties of polymers can be improved with the addition of nanofillers. Therefore, this work evaluates the effect of the combination of montmorillonite Cloisite 30B (OMt) and graphene (Gr) on the dynamics compression properties obtained from a split‐Hopkinson pressure bar (SHPB) test for nanostructured maleinized high‐density polyethylene (HDPE). The nanofillers are incorporated into the polymeric matrix in its molten state, and their dispersion is evaluated through x‐ray diffraction and transmission electron microscopy analyses. Thermal analysis, including differential scanning calorimetry and thermogravimetric analysis are performed. Additionally, the viscoelastic behavior of the materials is studied from the results of storage and loss modulus obtained by dynamic‐mechanical analysis. Under the SHPB test conditions, it is possible to evaluate the material stress–strain curve, identifying its yield point, compressive strength, and deformations to calculate the elastic stiffness and toughness of the material. The nanocomposite with 3% OMt and 0.75% Gr (wt.%) shows the highest average compressive strength and toughness values. Furthermore, this sample shows similar Tpeak temperature, improved crystallinity index, storage, and loss modulus, with similar glass transition temperature compared to the HDPE sample. [ABSTRACT FROM AUTHOR]

Understanding how dangling fragments of polyurethanes (PU) affect its microphase separation structure and damping properties can provide insights for designing desired materials at the molecular scale. By varying the types of diol extenders (such as 1,2‐ethyleneglycol, 1,2‐propanediol, and 1,2‐butanediol), PU samples with different dangling residues were successfully synthesized. Using atomic force microscopy and small‐angle x‐ray scattering, we confirmed that the introduction of dangling chains disrupts microphase separation and demonstrated a correlation between the degree of suppressed microphase separation and the size of the dangling residues. Fourier transform infrared spectroscopy and molecular dynamics simulations confirmed that dangling chains reduce the hydrogen bonding index while increasing the phase compatibility between soft and hard segments. Differential scanning calorimetry (DSC) measurements revealed an increased glass transition temperature (Tg), indicating hindered movement of backbone segments due to dangling chains. Moreover, lengthening the dangling chains further decreased Tg. Dynamic mechanical analysis (DMA) demonstrated improved damping properties with the introduction of dangling chains, although increasing chain length led to deteriorating damping properties, consistent with observations from DSC. These findings suggest that the variations in macroscopic properties of PU induced by dangling chains are linked to hydrogen bonding interactions and micromorphology at the molecular level. [ABSTRACT FROM AUTHOR]

In this work, a novel approach is taken to enhance the thermal conductivity and mechanical properties of composites by developing highly efficient thermally conductive PVDF‐based composites. This is developed by incorporating tetra‐pod zinc oxide whiskers (T‐ZnOw) in conjunction with multiwalled carbon nanotubes (MWCNT) to form binary hybrid fillers within a polyvinylidene fluoride (PVDF) matrix. Polydopamine (PDA), characterized by physical adsorption, is selected for surface coating on T‐ZnOw since T‐ZnOw is easy to self‐agglomerate and difficult to modify by physical and chemical methods. The coating aims to improve the dispersibility of T‐ZnOw and reduce the interfacial thermal resistance with the substrate. MWCNT is oxidized to improve its dispersion ability while strengthening the interaction with the matrix, due to the absence of interaction between MWCNTs and polymer matrix and poor dispersibility with the matrix. The dispersity of PDA@T‐ZnOw and o‐MWCNT is improved, and the three‐dimensional hybrid network structure can be better constructed to improve the thermal conductivity of the composite membrane. At a filler content of 25 wt%, the thermal conductivity reaches 0.302 W m−1 K−1 for T‐ZnOw–MWCNT–PVDF and 0.222 W m−1 K−1 for PDA@T‐ZnOw–o‐MWCNT–PVDF. [ABSTRACT FROM AUTHOR]

A structural adhesive series of biomass-based polyurethane (Biomass-PU) is synthesized using polypropylene glycol (PPG2000), isosorbide-based polyol (RPO300) as polyols, isophorone diisocyanate (IPDI) as an isocyanate and 4-tert-butylphenol (BP) as a capping agent. Three different equivalent ratios of PPG2000/RPO300, 9/1 (Biomass-PU1), 7/3 (Biomass-PU2), and 1/1 (Biomass-PU3), are evaluated to determine the effect of isosorbide-based polyol content on the properties and the optimizing formulation of biomass-PU structure adhesive. The 9/1 ratio of PPG2000/RPO300 substantially leads to the improvement of impact strength by up to 35 MPa, and the PPG2000/RPO300 = 9/1 ratio exhibits better thermal properties and impact strength than those of other ratios. To achieve more compatibility between biomass-PU structure adhesive and core–shell rubber (CSR) toughener, novel CSRs are successfully synthesized using acryl-PU as a shell and biomass-based PU as a core. The chemical structure of biomass-PU structure adhesives is analyzed through FT-IR Spectroscopy and NCO% titration. Thermal properties are evaluated using TGA and DSC analysis. Their molecular weights are measured by GPC. Also, the core–shell rubber (CSR) with a polyurethane shell is prepared to reinforce the impact strength of Biomass-PU structure adhesive. [ABSTRACT FROM AUTHOR]

Highlights Increasing miniaturization and integration of microelectronic devices have led to an unprecedented attention on heat dissipation and signal transmission of electronic equipment. However, the mostly used method to enhance the thermal conductivity of polymers by adding thermally conductive fillers usually results in the increase of dielectric constant (Dk). It was still challenging to synergistically achieve low Dk and high thermal conductivity of polymer‐matrix composites. Herein, hydroxylated boron nitride nanosheet (BNNS‐OH) with a high yield of 35.67% was prepared by the liquid ultrasonic exfoliation under the assistance of sodium cholate (SC), and grafted with (1H,1H,2H,2H‐perfluorodecyl) trimethoxy silane to prepare fluorinated boron nitride nanosheets (F‐BNNS), which can uniformly disperse in liquid silicone rubber (LSR) and reduce the Dk of LSR composites. The thermal conductivity of LSR composites with 20 wt% F‐BNNS reached 0.489 W·m−1·K−1, showing an increase of 307.35% in comparison with pure LSR (0.12 W·m−1·K−1). Meantime, the Dk of as‐obtained LSR/F‐BNNS (20 wt%) composites is reduced from 3.4 to 2.6, and the dielectric loss (Df) is less than 0.012. The facile and rational design of fluorinated BNNS offers a new insight for the high‐end electronic packaging materials. A new method of exfoliation and fluorinated treatment of h‐BN was proposed. The LSR composites achieved an ultralow Dk of 2.63 via fluorinated BNNS. Thermal conductivity of LSR composites increased by 307.35% than pure LSR. [ABSTRACT FROM AUTHOR]

Highlights Thermal expansion of materials is a critical factor influencing their dimensional stability. This study explores the regulation of thermal expansion in composite materials through the incorporation of carbon fibers and zirconium tungstate particles. The influence of fiber length on the thermal expansion behavior of these composites was investigated. The investigation reveal that the variation in the relative elongation ratio (dl/L0) of the carbon fiber‐reinforced zirconium tungstate composites is nonlinear, characterized by an initial increase, subsequent decrease, and a final resurgence. Notably, an increase in fiber length results in a mitigated rate of increase in the (dl/L0) ratio. Furthermore, composites fabricated with shorter fibers exhibit a higher coefficient of thermal expansion (CTE). Upon elevating the temperature to 250°C, the CTE for composites reinforced with 100 and 500 mesh carbon fibers escalate to 24.5 × 10−6/K and 74.6 × 10−6/K, respectively. These values represent an 8% and 116% enhancement relative to those measured at 50°C. The thermal expansion properties are improved by adding carbon fiber and ZrW2O8 nanoparticles. Utilizing fiber lengths ranging from 100 to 500 mesh effectively diminishes the CTE. The Cf‐ZrW2O8/9621 composite exhibits non‐linear behavior in its dl/L0 ratio. Within the range, longer fibers are more beneficial for reducing the CTE. [ABSTRACT FROM AUTHOR]

Here, we propose a sensing scheme based on an all-dielectric metamaterial with the smooth reflection and transmission spectral lines in 10-60THz, and verify the applications of the measuring the resonance characteristics of Xuan paper samples. The reflection and thermal conductivity of Xuan paper samples enhance with the concentration of alum water increasing and weaken due to the thickness increasing. These results provide a solid foundation for this metamaterials in measuring the reflective and thermal resonance properties of Xuan paper samples. [ABSTRACT FROM AUTHOR]

This work addresses the problem of obtaining of Ca 3 Co 4 O 9+δ -based ceramics with enhanced thermoelectric performance. Phase-inhomogeneous layered calcium cobaltite ceramics with cationic nonstoichiometry were prepared by solid-state reactions method and a field assisted sintering technology (FAST). Comprehensive experimental characterizations were conducted on the prepared bulk samples, focusing on their phase composition, as well as thermal (including thermal expansion, thermal diffusivity, and thermal conductivity), electrical (encompassing electrical conductivity and the Seebeck coefficient), and functional properties (such as power factor and figure-of-merit). The FAST technique allowed to obtain ceramics with low porosity and high electrical conductivity, which increased as the Ca:Co ratio within the samples decreased, while sample phase inhomogeneity considerably increased the Seebeck coefficient. The best thermoelectric performance was demonstrated for cationic nonstoichiometric Ca 3 Co 4.4 O 9+δ , which power factor and figure-of-merit values at 825 °C reached 427 μW⋅m−1⋅K−2 and 0.146, respectively. • Ca 3 Co 4 O 9+δ -based ceramics prepared by field assisted sintering technology possessed low porosity and high conductivity. • Electrical conductivity of bulk samples increased at decreasing Ca:Co ratio. • Phase inhomogeneity of prepared ceramics increased the Seebeck coefficient. • Ca 3 Co 4.4 O 9+δ ceramics showed the best thermoelectric performance. [ABSTRACT FROM AUTHOR]

Low-cost amorphous nano-carbon (ANC) was employed as an absorbent to modify the microwave performance of AlN ceramics (AlN-4 wt% Y 2 O 3 - x wt% C, x = 0, 2.0, 3.8, 3.9, 4.0) via hot-pressing sintering, and the thermal and mechanical properties were also investigated. With the increase of ANC content from 0 to 4.0 wt%, the relative density of AlN composite decreases from 3.28 g cm−3 to 3.16 g cm−3 when sintered at 1800 °C for 2 h, and with the increase of sintering temperature from 1700 °C, the density of the 4.0 wt% ANC doped AlN composite presents trend of increase and reaches the maximum value of 3.16 g cm−3 at 1800 °C and then decreases. The XRD pattern shows that the composites are composed of AlN and Y–Al–O (YAG, YAP, YAM et al.) phases. SEM results indicate that average grain sizes for AlN and secondary phases gradually decrease with increasing carbon content, suggesting inhibited grain growth due to ANC addition. No obvious changes in phase constitution nor intensity changes were detected with the increase in carbon content and sintering temperature. As the carbon content increases from 0 to 4.0 wt%, the dielectric constant gradually increases from ∼9 to 13.89 at 10 GHz, the dielectric loss gradually increases from the vicinity of 10−3 to 0.38 at 10 GHz, and the reflective loss decreases from −27.92 dB to −49.40 dB, the thermal conductivity of the AlN-ANC composite decreases from 116.63 W m−1 K−1 to 50.13 W m−1 K−1. In addition, with 4.0 wt% ANC addition, the dielectric constant, dielectric loss, reflective loss, hardness, elastic modulus, bending strength, and fracture toughness are 13.89, 0.38, 49.40 dB, 6.4 ± 0.4 GPa, 262 GPa, 268.78 MPa, and 1.4 ± 0.1 MPa m1/2, respectively. Its ability to efficiently absorb microwave energy enhances the performance of devices including radar systems, communication equipment, and microwave heating systems, making it a promising candidate for microwave vacuum electronic applications. [ABSTRACT FROM AUTHOR]

In order to suppress the damage of cable insulation caused by water tree structure formed by micro‐droplets at insulation defects in low density polyethylene (LDPE) materials under AC electric field. In this paper, the siloxane group is grafted onto LDPE by melt grafting method, and different content of comonomer styrene (St) is added to improve the grafting rate of siloxane group grafted polyethylene. The effect of St on the microscopic characteristics of LDPE grafted KH570 is studied. In order to verify the accuracy and timeliness of water tree self‐healing of grafted polymer insulation materials, the microstructure characteristics of LDPE ungrafted and grafted polymer samples are analyzed by Fourier transform infrared spectroscopy, gel content test, and differential scanning calorimeter. Second, the AC dielectric properties of LDPE ungrafted and grafted polymer samples are studied by AC breakdown experiment and space charge test. Finally, the water tree length, micropore defects, and self‐healing of the samples are observed by optical microscopy and polarization and depolarization current method, and the changes of chemical composition in the water tree area before and after aging are analyzed by infrared spectroscopy. The principle and mechanism of repairing water tree defects with grafted monomers are explained. This paper not only combines the previous research results of self‐healing materials, but also provides a new method for the preparation process of LDPE grafted polymer, which has a good research prospect in practical application. [ABSTRACT FROM AUTHOR]

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

To improve the comprehensive properties of polybutylene furandicarboxylate (PBF), 2,5‐furandicarboxylic acid (2,5‐FDCA), and aliphatic chain diol 1,8‐octanediol and 1,4‐butanediol were used as monomers to synthesize a series of bio‐based polybutylene glycol‐octanediol 2,5‐furandicarboxylate (PBOF). The results showed that the chemical composition of PBOF could be controlled through the molar ratio of monomers. Compared with PBF, as the proportion of octanediol segments gradually increased, PBOF could gradually transform from semi‐crystalline thermoplastic to amorphous form, and the glass transition temperature (Tg) gradually decreased. The crystallization ability reduced but a part of the crystal area was still retained. The copolyesters still has a decomposition temperature above 370°C, indicating excellent thermal stability. The introduction of the octanediol segment significantly improved the tensile mechanical properties and flexibility of the POBF copolyester. These meet the requirements for the preparation of bio‐based engineering plastics. The water absorption rate of PBOF showed that it may have certain degradable potential. PBOF copolyesters have potential application prospects in bio‐based medical plastics and biodegradable packaging polymer materials after copolymerization modification. [ABSTRACT FROM AUTHOR]

The study primarily focuses on the in situ synthesis of polystyrene (PS) and copper oxide (CuO) nanocomposites. An extensive analysis was conducted on the optical, thermal, mechanical, and electrical properties of PS with different CuO concentrations. The effective inclusion of CuO into PS was characterized by Fourier-transform infrared spectroscopy (FTIR), UV–visible spectroscopy, filed emission scanning electron microscopy (FE-SEM), X-ray diffractometry (XRD), differential scanning calorimetric analysis (DSC) and thermal gravimetric analysis (TGA). The reinforcement of CuO into the PS was established through FTIR. The optical bandgap energy deduced from UV–visible spectra decreases with CuO addition, whereas the refractive index rises significantly with the addition of CuO nanoparticles up to 7 mass%. The XRD analysis revealed the amorphous to crystalline transformation of PS with the homogeneous dispersion of nanoparticles. The SEM–EDX analysis revealed the uniform distribution of CuO nanofillers in the PS matrix. The CuO addition considerably increased the glass transition temperature and thermal stability of PS. The tensile strength, impact resistance and hardness of nanocomposite were significantly increased with the loading of CuO in the polymer matrix. The AC conductivity and dielectric constant of the PS was improved with the addition of CuO nanoparticles. The effect of temperature on conductivity, activation energy, and pre-exponential factor was determined using the universal power law and the Arrhenius equation. The highest electrical and mechanical properties were observed for 7 mass% nanocomposite. The synthesized PS/CuO nanocomposites with excellent optical characteristics, thermal stability, electrical conductivity, dielectric constant and mechanical strength can be used in supercapacitors and flexible nano-electronic devices. [ABSTRACT FROM AUTHOR]

In this study, Ni20Ti50Sn30 (atomic %) sample was prepared using the arc melting method. Some thermodynamic parameters (phase transformation temperatures, PTT; enthalpy, ΔH; and phase transformation hysteresis, H) obtained from the phase transformations of the alloy were determined using differential scanning calorimetry (DSC). The sample exhibited high-temperature shape memory alloy (HTSMA) properties. X-ray (XRD) analysis was performed to determine the crystal structure properties at the alloy. The presence of B2, B19′, Ti2Ni, β-Ti, Ni3Sn4, TiNiSn and Ti3Sn phases was identified through X-ray analysis of the alloy. Scanning electron microscopy (SEM) was used to examine the pre- and post-corrosion surface morphologies of the sample, with EDX analysis being performed to reveal chemical structure determinations (matrix phases, precipitates and weathering zones). The presence of dendritic arms was observed, while martensite plates were absent in all SEM images. Particularly in the SEM image taken after corrosion, it was noted that the TiO2 layer placed on the surface of the matrix rich in Ti elements altered the surface morphology of the alloy. The presence of Ti and O elements in the post-corrosion EDX analysis confirmed the existence of this layer. Biocompatibility studies of the alloy were conducted using potentiodynamic corrosion tests and electrochemical impedance spectroscopy (EIS) methods. It was determined that the NiTiSn sample was in the excellent stability class according to corrosion standards. [ABSTRACT FROM AUTHOR]

This study aims to assess the effect of physical modification techniques on the properties of millet starch. The starch isolated from barnyard millet (Echinochloa frumentacea) is subjected to ultrasonication (20 kHz; 30 and 60 min) and gamma irradiation (5 and 10 kGy). The protein content decreases slightly (by 2.5–3.8%) with gamma irradiation and significantly (by 5.7–6.9%) with ultrasonication. As compared to the native starch (20.56%), the amylose content of ultrasonicated starch is significantly higher (21.42% and 21.88%), while it is significantly lower (19.73% and 19.18%) for gamma‐irradiated starch. The swelling power of the native starch (13.57%) increases significantly with ultrasonication (14.21% and 14.33%) treatment; while it decreases significantly with gamma irradiation (13.17% and 12.25%) treatment. The solubility increases to 11.23%, 11.19%, 12.09%, and 13.31% from 10.45%, with both modifications. The peak viscosity of modified starches decreases significantly (2872 and 2700 cP) as compared to the native starch (3832 cP). The starches exhibit a greater value for storage modulus (G′) as compared to loss modulus (G″), reflecting their elastic nature. These transformations in the microstructure, gelatinization, and physicochemical properties of native starch can further be explored for food and textile industrial applications. [ABSTRACT FROM AUTHOR]

One of the most advanced and versatile nanoscale diagnostic tools is atomic force microscopy. By enabling advanced imaging techniques, it allows us to determine various assets of a surface, including morphological, electrical, mechanical, magnetic, and thermal properties. Measuring local current flow is one of the very important methods of evaluation for, for instance, photovoltaic materials or semiconductor structures and other nanodevices. Due to contact areas, the current densities can easily reach above 1 kA/m2; therefore, special detection/measurement setups are required. They meet the required measurement range, sensitivity, noise level, and bandwidth at the measurement scale. Also, they prevent the sample from becoming damaged and prevent unwanted tip–sample issues. In this paper, we present three different nanoscale current measurement solutions, supported with test results, proving their performance. [ABSTRACT FROM AUTHOR]

This review explores the integration of graphene and liquid crystals to advance sensor technologies across multiple domains, with a focus on recent developments in thermal and infrared sensing, flexible actuators, chemical and biological detection, and environmental monitoring systems. The synergy between graphene's exceptional electrical, optical, and thermal properties and the dynamic behavior of liquid crystals leads to sensors with significantly enhanced sensitivity, selectivity, and versatility. Notable contributions of this review include highlighting key advancements such as graphene-doped liquid crystal IR detectors, shape-memory polymers for flexible actuators, and composite hydrogels for environmental pollutant detection. Additionally, this review addresses ongoing challenges in scalability and integration, providing insights into current research efforts aimed at overcoming these obstacles. The potential for multi-modal sensing, self-powered devices, and AI integration is discussed, suggesting a transformative impact of these composite sensors on various sectors, including health, environmental monitoring, and technology. This review demonstrates how the fusion of graphene and liquid crystals is pushing the boundaries of sensor technology, offering more sensitive, adaptable, and innovative solutions to global challenges. [ABSTRACT FROM AUTHOR]

As a critical material for high-temperature components of aero-engines, the mechanical properties of Ti65 alloy, subjected to high-temperature and long-term thermal exposure, directly affect its service safety. The room-temperature tensile properties of the Ti65 alloy after thermal exposure to temperatures ranging from 450 °C to 650 °C for 100 h were investigated. The results indicate that as the thermal exposure temperature increases, the strength of Ti65 alloy initially increases and then decreases, while ductility exhibits a decreasing trend. The strength of the thermally exposed alloy positively correlates with the size and content of the α2 phase. The ductility of the thermally exposed alloy is comprehensively influenced by the surface oxidation behavior, α2 phase, and silicides. After the prolonged thermal exposure, stress concentration at the crack tips within the oxide layer was enhanced with the increased thickness of the surface TiO2 oxide layer, leading to premature fracture due to reduced alloy ductility. Furthermore, the α2 phase in the matrix promotes the planar slip of dislocations, while silicides at the α/β phase boundaries hinder dislocation motion, causing dislocation pile-ups. Both behaviors facilitate crack nucleation and deteriorate alloy ductility. [ABSTRACT FROM AUTHOR]

In the present research, the impacts of Ce additions at various concentrations (0, 1.0, 3.4, and 4.0 wt.%) on the evolution of the microstructure, mechanical properties, and thermal conductivity of as-cast and as-extruded Mg-3Sn alloys were investigated. The findings demonstrate that adding Ce caused the creation of a new ternary MgSnCe phase in the magnesium matrix. Some new Mg17Ce2 phases are generated in the microstructure when Ce levels reach 4%. The thermal conductivity of the Mg-3Sn alloy is significantly improved due to Ce addition, and the Mg-3Sn-3.4Ce alloy exhibits the highest thermal conductivity, up to 133.8 W/(m·K) at 298 K. After extrusion, both the thermal conductivity and mechanical properties are further improved. The thermal conductivity perpendicular to the extrusion direction of Mg-3Sn-3.4Ce alloy could achieve 136.28 W/(m·K), and the tensile and yield strengths reach 264.3 MPa and 227.2 MPa, with an elongation of 7.9%. Adding Ce decreases the dissolved Sn atoms and breaks the eutectic α-Mg and Mg2Sn network organization, leading to a considerable increase in the thermal conductivity of as-cast Mg-3Sn alloys. Weakening the deformed grain texture contributed to the further enhancement of the thermal conductivity after extrusion. [ABSTRACT FROM AUTHOR]

The study examined the possibility of intercalation of montmorillonite with neomycin in an aqueous drug solution and the factors influencing the effectiveness of this process, such as the ion exchange capacity and process conditions, including the time and temperature of incubation with the drug. X-ray diffractometry (XRD), infrared spectroscopy (FTIR), thermal analysis (DSC/TG), and Zeta potential measurement were used to confirm drug intercalation as well as to investigate the nature of clay–drug interactions. The obtained conjugates with the most favorable physicochemical properties were also tested for antibacterial response against Gram-negative bacteria (Escherichia coli) to confirm that the bactericidal properties of neomycin were retained after intercalation and UV–VIS spectrophotometry was used to examine the kinetics of drug release from the carrier. The results of the conducted research clearly indicate the successful intercalation of neomycin in montmorillonite and indicate the influence of process parameters on the properties of not only the conjugates themselves but also the properties of the intercalated drug, particularly its bactericidal activity. Ultimately, a temperature of 50 °C was found to be optimal for effective drug intercalation and the conjugates obtained within 2 h showed the highest antibacterial activity, indicating the highest potential of the thus-obtained montmorillonite conjugates as neomycin carriers. [ABSTRACT FROM AUTHOR]

Sea surface temperature (SST) is an important factor in the marine environment and has significant impacts on climate, ecology, and maritime activities. Most existing SST prediction methods consider the ocean as a uniform field and use a uniform grid to predict SST. However, the marine environment is a complex system, and factors such as solar radiation, differences in land and sea thermal properties, and ocean circulation lead to uneven spatial distributions of SSTs. We propose a non-uniform grid construction method based on an SST spatial gradient to encode SST data, as well as a Non-uniform Grid Graph Convolutional Network (NGGCN) model. The NGGCN consists of two spatiotemporal modules, each of which extracts spatial features from the GCN module, captures temporal correlations through the GRU module, and performs feature restoration and output results through the fully connected module. We selected data from the Yellow Sea and Bohai Sea to validate the effectiveness of the NGGCN in predicting SST at different time scales and prediction steps. The results indicate that our model shows a significant improvement in prediction performance compared to other models. [ABSTRACT FROM AUTHOR]

Fluorosilicone was combined with aluminum trihydrate (ATH) to induce synergistic flame-retardant and thermal-resistant properties. The surface of ATH was modified with four different silane coupling agents. The flammability and mechanical properties of the fluorosilicone/ATH composites were assessed using an UL94 vertical test and a die shear strength test. The change in shear strength was investigated under aging for 1000 h at −55 °C and 150 °C. Pure fluorosilicone had inherent fire resistance and thus achieved a V-0 rating even at 20 wt.% ATH loading. Upon addition of ATH treated with 3-glycidoxypropyl trimethoxysilane, the composites exhibited the highest shear strength of 3.9 MPa at 23 °C because of the additional crosslinking reaction of fluorosilicone resin with the epoxide functional group of the coupling agent. Regardless of the types of coupling agents, the composites exhibited similar flame retardancy at the same ATH content, with a slight reduction in shear strength at 180 °C and 250 °C. The shear strength of the adhesives gradually decreased with aging time at −55 °C, but increased noticeably from 3.9 MPa to 11.5 MPa when aged at 150 °C due to the occurrence of the additional crosslinking reaction of fluorosilicone. [ABSTRACT FROM AUTHOR]

Polymer coatings are widely used in industries for protection, decoration, and specific applications, typically including volatile organic compounds (VOCs) to achieve low viscosity. The growing environmental concerns and the anticipated limits on fossil feedstock have driven the coating industry towards eco-friendly alternatives, with UV-curing technology emerging as a promising solution due to its energy efficiency, low-temperature operation, reduced VOC emissions, and high curing speed. Polyurethane acrylates (PUAs) are critical in UV-curable formulations, offering excellent flexibility, impact strength, optical, and adhesion properties. However, UV-cured PUA coatings face limitations in thermal stability and tensile strength, which can be addressed by incorporating fillers. This study investigates the effects of multi-functionalized hexagonal boron nitride (hBN) nanoparticles on the mechanical, thermal, optical, and adhesion properties of UV-cured PUA films and coatings for pre-coated metals. The results demonstrated that incorporating hBN nanoparticles enhanced the mechanical and thermal properties of the nanocomposite films, with optimal performance observed at 0.5% hBN loading. Despite the improved properties, the FTIR spectra indicated that the low concentration of hBN did not produce significant changes, potentially due to the overshadowing signals from the difunctional polyurethane acrylate. [ABSTRACT FROM AUTHOR]

As an important biodegradable and partially biobased copolyester, poly(butylene succinate-co-terephthalate) (PBST) possesses comparable thermal and mechanical properties and superior gas barrier performance when compared with poly(butylene adipate-co-terephthalate) (PBAT), but it was found to display poorer melt processability during pelletizing and injection molding. To make clear its melt crystallization behavior under rapid cooling, PBST48 and PBST44 were synthesized, and their melt crystallization was investigated comparatively with PBAT48. PBST48 showed a PBAT48-comparable melt crystallization performance at a cooling rate of 10 °C/min or at isothermal conditions, but it showed a melt crystallization ability at a cooling rate of 40 °C/min which was clearly poorer. PBST44, which has the same mass composition as PBAT48, completely lost its melt crystallization ability under the rapid cooling. The weaker chain mobility of PBST, resulting from its shorter succinate moiety, is responsible for its inferior melt crystallization ability and processability. In comparison with PBAT48, PBST48 displayed higher tensile modulus, and both PBST48 and PBST44 showed higher light transmittance. The findings in this study deepen the understanding of PBST's properties and will be of guiding significance for improving PBST's processability and application development. [ABSTRACT FROM AUTHOR]

Petroleum-based food packaging causes environmental problems such as waste accumulation and microplastic generation. In this work, biobased films from stable polyelectrolyte complex suspensions (PECs) of xylan and chitosan (70 Xyl/30 Ch wt% mass ratio), at different concentrations of citric acid (CA) (0, 2.5, 5, 7.5 wt%), were prepared and characterized. Films were treated at two temperatures (135 °C, 155 °C) and times (30 min, 60 min) to promote covalent crosslinking. Esterification and amidation reactions were confirmed by Fourier Transform Infrared Spectroscopy and Confocal Raman Microscopy. Water resistance and dry and wet stress–strain results were markedly increased by thermal treatment, mainly at 155 °C. The presence of 5 wt% CA tended to increase dry and wet stress–strain values further, up to 88 MPa—10% (155 °C for 60 min), and 5.6 MPa—40% (155 °C for 30 min), respectively. The UV-blocking performance of the films was improved by all treatments, as was thermal stability (up to Tonset: 230 °C). Contact angle values were between 73 and 84°, indicating partly wettable surfaces. Thus, thermal treatment at low CA concentrations represents a good alternative for improving the performance of Xyl/Ch films. [ABSTRACT FROM AUTHOR]

Thermoset-based polymer composites containing functional fillers are promising materials for a variety of applications, such as in the aerospace and medical fields. However, the resin viscosity is often unsuitably high and thus impedes a successful filler dispersion in the matrix. This challenge can be overcome by incorporating suitable low-viscosity modifiers into the prepolymer. While modifiers can aptly influence the prepolymer rheology, they can also affect the prepolymer curing behavior and the mechanical and thermal properties of the resulting matrix material. Therefore, this study investigates the effects that a commercial-grade low-viscosity additive (butyl glycidyl ether) has on a common epoxy polymer system (diglycidyl ether of bisphenol-A epoxy with a methylene dianiline curative). The weight percentage of the modifier inside the epoxy was varied from 0 to 20%. The rheological properties and cure kinetics of the resulting materials were investigated. The prepolymer viscosity decreased by 97% with 20 wt% modifier content at room temperature. Upon curing, 20 wt% modifier addition reduced the exothermic peak temperature by 12% and prolonged the time to reach the peak by 60%. For cured material samples, physical and thermo-mechanical properties were characterized. A moderate reduction in glass transition temperature and an increase in elastic modulus was observed with 20 wt% modifier content (in the order of 10%). Based on these findings, the selected material system is seen as an expedient base for material design due to the ease of processing and material availability. The present study thus provides guidance to researchers developing polymer composites requiring reduced prepolymer viscosity for successful functional filler addition. [ABSTRACT FROM AUTHOR]

The objective of this study was to prepare a co-amorphous blend of BCS class II drug, glipizide (GPZ), using arginine (ARG) as co former. The co-amorphous GPZ-ARG mixtures (molar ratios 1:1, 1:2 and 2:1) were prepared by mechanical activation (ball milling) with different milling times. The obtained mixtures were characterized with respect to their thermal properties, possible molecular interactions, dissolution properties and physical stability and compared to the behaviour of pure crystalline form. Solid-state characterization of mixture revealed amorphization of GPZ after 90 min. of ball milling. GPZ-ARG co amorphous mixture (1:2) upon ball milling for 90 min. exhibited maximum solubility (3876.8 µg/ml) compared to pure drug (300.89 µg/ml). The resulting best co amorphous blend was incorporated into pellets which were prepared by extrusion spheronisation technique. The parameters related to process of pelletisation and product related parameters were optimized by using 4-factor, 5-level Central Composite Design. The pellets containing co amorphous blend, prepared by using optimal parameter settings, showed 95.67% Drug Release in 120 min. (F23). The co-amorphous mixture and the optimized formulation were found to be stable when subjected to stability study as per ICH guideline. It was concluded that co amorphous is a promising approach to overcome the solubility constraint of Glipizide which would be helpful in better management of the disease. [ABSTRACT FROM AUTHOR]

Summary: The present study investigates the impact of germination (72 h) on physicochemical, protein solubility, in vitro protein digestibility, antinutrient, antioxidant, and structural properties of sorghum flour. Germination resulted in a reduction of crude protein, fat, fibre, and ash. However, it significantly improved the DPPH (58.42%–69.44%), total phenolic content (1.31–3.58 mg GAE g−1), and total flavonoid content (57.66–80.16 mg QE g−1). Germination also increased in vitro protein digestibility (50.12%–75.52%) and Fe2+ chelating activity (11.18%–48.06%), while reducing antinutrients such as phytic acid (176 to 86 mg/100 g) and tannin (3.53–2.16 mg/100 g). Structural analyses (XRD and FTIR) revealed modifications in crystalline and molecular structures, while scanning electron microscopy showed disrupted starch granules in germinated flour. These findings suggest that germination enhances the functional and nutritional properties of sorghum flour, making it more suitable for various applications in food products. [ABSTRACT FROM AUTHOR]

Manufacturing of several products with better quality and features in industries depends upon the cooling processes. Based on the thermal properties, this research aims to investigate the effect of dissipative heat in non-Newtonian Jeffrey nanofluid flow along horizontal channels embedded in a porous matrix. Due to cross-diffusion, the time-dependent electrically conducting fluid presents the role of Brownian motion and thermophoresis. Further, the conjunction of binary chemical reactions encourages the flow phenomena. The appropriate choice of the similarity variables helps to transform a dimensional system of the governing equations into their non-dimensional form. Further, the shooting-based Runge–Kuta–Fehlberg method is used to solve the transformed governing equations. The structural behaviour of the characterising constraints is presented via graphs and described briefly. The validation with the earlier result is presented in a particular case showing a good correlation. [ABSTRACT FROM AUTHOR]

The susceptibility of either oxidation into Sn(IV) or disproportionation into Sn(IV) and Sn(0) limits the study of metal tin‐(II)‐borate ceramics. We report mullite‐type SnCrBO4 and SnVBO4 synthesized in sealed quartz tubes by conventional solid‐state method. X‐ray powder diffraction data Rietveld refinements confirm that both compounds are isostructural to PbMBO4 phases for M = Al, Ga, Cr, Mn, and Fe. The end‐members show a complete miscibility within the Sn(Cr1−xVx)BO4 solid solution. Both the microstructural (average crystallite size, microstrain, and degree of crystallinity) and crystal structural (metric parameters, bond lengths, polyhedral volume, and polyhedral distortion) parameters are observed with respect to the compositional x‐value. The stereochemical activity of the 5 s2 lone electron pairs of Sn2+ cations has been measured by using the Wang–Liebau eccentricity parameter. The structural features are complemented by 119Sn Mössbauer, Raman, and Fourier‐transformed infrared spectroscopy. The 119Sn Mössbauer isomer shifts and the quadrupole splitting values confirm the SnO4 coordination and an Sn(II) valence state. The electronic band gap has been calculated from the UV/Vis diffuse reflectance spectra, which slightly increases with successive decrease of the cationic radius from V to Cr. Temperature‐dependent inverse DC magnetic susceptibility suggests that SnCrBO4 and SnVBO4 are antiferromagnetic and ferromagnetic (FM) with a Néel temperature of 17.2(1) K and a Curie temperature of 29.8(1) K, respectively. Alike the end‐member SnVBO4, Sn(Cr0.5V0.5)BO4 is also found to be a rare FM insulator. The thermal stability decreases with increasing vanadium content in the solid solution. [ABSTRACT FROM AUTHOR]

Thermal and electrical properties were investigated for five nominally phase‐pure high entropy carbide ceramics. The compositions (Hf0.2Nb0.2Ta0.2Ti0.2Zr0.2)C, (Cr0.2Hf0.2Ta0.2Ti0.2Zr0.2)C, (Hf0.2Mo0.2Ta0.2Ti0.2Zr0.2)C, (Hf0.2Ta0.2Ti0.2W0.2Zr0.2)C, and (Hf0.2Mo0.2Ti0.2W0.2Zr0.2)C were synthesized by carbothermal reduction of oxides. The thermal diffusivity and heat capacity were measured from room temperature to 1800°C. The room temperature thermal conductivity ranged from 5.1 W/mK for (Hf0.2Mo0.2Ti0.2W0.2Zr0.2)C to 9.0 W/mK for (Cr0.2Hf0.2Ta0.2Ti0.2Zr0.2)C. The thermal conductivity increased over the temperature range with maximum conductivities of 19.6 W/mK measured for (Hf0.2Mo0.2Ta0.2Ti0.2Zr0.2)C to 29.7 W/mK for (Cr0.2Hf0.2Ta0.2Ti0.2Zr0.2)C at 1800°C. The electron contribution to thermal conductivity calculated from measured electrical resistivity varied from 41% to 52% of the total thermal conductivity. The tungsten and molybdenum containing compositions had higher phonon contributions while the niobium and chromium containing compositions had nearly equal electron and phonon contributions to thermal conductivity. [ABSTRACT FROM AUTHOR]

In this paper large deformation of the skew microplate made of laminated composite enhanced with graphene nanosheets is investigated using first shear deformation theory (FSDT) when the plate undergoes combination of mechanical and thermal loads. Halpin-Tsai model is utilised to model mechanical properties while for thermal properties Schapery model is considered. First, shear deformation of the plate was obtained while using Green-Lagrange tensor the non-linear strain of the microplate is extracted using the von-Karman assumptions. Then, by Modified Coupled Stress Theory (MCSD), the components of Cauchy and Couple stress tensors are specified. Finally, using Hamilton Principle the governing equation of the microplate and boundary conditions are computed. After deriving analytical governmental equation results are presented for the simple support boundary condition and the proposed model is validated by previously reported data and it proves to be promising. Primary results showed that with raising skew angle deflection and bending moment decreases which means microplate becomes more rigid in higher skew angles. Higher mechanical loads lead to higher deflections and bending moments. Four different configurations of the layers were analysed from which angle-ply configuration possessed highest deflection and bending while UD configuration revealed the lowest values of deflection and bending moment. [ABSTRACT FROM AUTHOR]

The present study intends to investigate the impact of fractionation and micronization on the compositional, functional, and thermal characteristics of two protein concentrates derived from corn and barley. Fractionation of protein concentrates (by sieving) resulted in three fractions, i.e., fine (< 100 µm), medium (100–300 µm), and coarse (> 300 µm), while micronization resulted in an average particle size of 30 µm. No specific pattern was observed between particle size and chemical composition of corn and barley protein concentrates due to the complex interplay between particle size, surface area, structural changes, and botanical origin. Protein solubility varied depending on the pH and particle size, showing that the coarse fraction exhibited higher solubility than the fine fraction. For both corn/barley protein concentrates, coarse fraction had higher water-/oil-holding capacity. The barley fine fraction showed high foaming capacity, while all proteins lacked emulsification ability. Across all samples, a trend of increasing enthalpy with decreased particle size was observed, except for micronized barley, where enthalpy decreased, indicating possible protein structural changes. Thus, variations in properties among fractions highlight the importance of particle size in determining the proteins' functionality for potential applications in food systems. [ABSTRACT FROM AUTHOR]

In the present study, the fatty acid composition (FAC), triacylglycerol (TAG) composition, crystallization, and melting behaviors of mango kernel fats (MKFs) extracted from seven Ivorian mango varieties—Amelie (AM), Kent (KT), Palmer (PR), Keitt (KI), Brooks (BR), Dadiani (DI), and Djakoumankoun (DN)—were characterized by complementary techniques: pNMR, DSC, polarized light microscopy, and X-ray diffraction. Regardless of the variety, Ivorian MKF is rich in stearic (St) and oleic (O) fatty acids. (72–84% of the total FA), with three main TAGs: StOSt (23.9–45.8%), StOO (15.5–25.8%), and StLSt (10.4–12.5%). Their crystallization onset temperature (Tco) ranged from 15 to 20 °C. All samples showed complete melting around 35 °C, except DN (~ 38 °C). The β-polymorph appeared to be the most predominant and stable polymorph for the seven MKFs. The thermal properties investigated were linked to monounsaturated and triunsaturated triacylglycerol content, indicating the significant influence of chemical composition. The fine analysis of the results allows the seven Ivorian varieties to be divided into four groups, based on both their physical properties and thermal behavior, and the StOSt wealth: hard high-StOSt fat (DN), half-hard medium-StOSt fat (DI, BR), soft low-StOSt fat (KT, PR, KI), and very-soft very-low-StOSt fat (AM). The seven investigated mango varieties from Ivory Coast might offer a wide range of applications in food, pharmaceutical, and cosmetic industries. [ABSTRACT FROM AUTHOR]

Characterization of isolated lignin and utilization of nanotechnology to produce nanolignin as a functional material are paramount. Lignin was extracted from acid-saccharification sugarcane trash (SCT-ASac) to produce acid-saccharification lignin (ASac-lignin). Then, lignin was further processed to nanolignin by a self-assembly dialysis process using THF:ethanol (1:1) as the solvent. The chemical, physical, and thermal properties of the lignin were evaluated, and the nanolignin size was confirmed via morphological analysis and PSA. SCT-ASac treatment prior to lignin isolation affects the structure of SCT and enhances the accessibility of lignin. Furthermore, this pretreatment can reduce residual carbohydrates, increasing the purity value. ASac-lignin has a nonconjugated phenolic group structure with a high number of β-O-4 bonds, a syringyl content, aromatic groups with low thermal stability, and a molecular weight with good phenolic hydroxyl content and total phenolic compounds. The obtained nanolignin is a spherical and more uniform particle with sizes less than 100 nm. ASac-nanolignin has the potential to be an environmentally friendly material in derivative lignin synthesis. [Display omitted] • acid-saccharification treatment of sugarcane trash to improve lignin accessibility. • the higher purity (94.23 %) was ASac-lignin. • ASac-lignin has good chemical traits, low thermal stability, and molecular weight. • nanolignin preparation using THF: Ethanol (1:1) and dialysis process. • ASac-nanolignin has a spherical shape with a particle size below 100 nm. [ABSTRACT FROM AUTHOR]

YBCO openwork structures were 3D-printed as cuboids with 4.5 × 4.5 × 2 mm dimensions and various filling degrees. Initial pycnometric data showed a slight variation in specimen densities (∼6.153 g/cm3), proving the production process uniformity. The consistency of YBCO superconducting phase (Y-123) was confirmed by Raman spectroscopy, X-ray diffraction and X-ray absorption spectroscopy. Microstructural and chemical homogeneity was proven by scanning electron microscopy with microprobe analysis. Transport (electrical and thermal) measurements accompanied by simulations of magnetic flux density at the produced structures revealed that they are heavily dependent of filling ratio and geometry. Additionally, this work proves that the 3D printing is an excellent method of fabricating high-quality superconducting structures of desired shapes accordingly to applicational demands. [ABSTRACT FROM AUTHOR]

To realize the high-brightness of yellow light-emitting diodes (LEDs), the yellow-emitting phosphor ceramics with high luminous efficiency (LE) are urgently explored. Based on the idea of spectrum regulation, the Lu 3 -x-y Gd y Al 5 O 12 : x Ce3+ (LuGdAG:Ce) phosphor ceramics were prepared via vacuum solid-state sintering. The effect of Gd3+ and Ce3+ content on the structure, luminescence and thermal properties of LuAG:Ce ceramics were investigated. The distortion ratio (D) of CeO 8 and bandgap were effectively modified via Gd3+ doping, resulting in massive red-shifting of Ce3+ emission (513→561 nm). The LEDs lighting encapsulated by LuGdAG:Ce ceramics changes from green to yellow. Importantly, the yellow LEDs with a LE up to 139.0 lm/W@180 W and a warm correlated color temperature (CCT) of 3620 K were achieved based ceramic Ce07Gd9. The LuGdAG:Ce phosphor ceramic has the best of luminescence performance in phosphor-converted yellow LEDs lighting so far, which is considered to be the highly promising color converter. [ABSTRACT FROM AUTHOR]

High-entropy ceramics have garnered significant attention in recent years owing to their exceptional properties and structural diversity. In this work, single-phase medium/high entropy ceramics, namely (Ca 0.2 Sr 0.4 Ba 0.4)(Zr 0.5 Ti 0.5)O 3 and (Ca 0.2 Sr 0.4 Ba 0.4)(Zr 0.1 Ti 0.9)O 3 , were successfully designed and prepared utilizing Spark Plasma Sintering (SPS). A comprehensive investigation was conducted into the phase structure, microscopic morphology, dielectric properties, and thermal behavior of these ceramics. It was observed that all ceramics maintained a cubic perovskite structure (space group: Pm 3 ‾ m), and the introduction of multi-element doping rendered them more stable across a wide frequency and temperature range. Notably, (Ca 0.2 Sr 0.4 Ba 0.4)(Zr 0.5 Ti 0.5)O 3 exhibited remarkably low dielectric loss (0.0001 at 1 kHz) at room temperature, along with excellent dielectric temperature stability (25–400 °C). By reducing the zirconium concentration in (Ca 0.2 Sr 0.4 Ba 0.4)(Zr 0.1 Ti 0.9)O 3 , a slight decrease in dielectric temperature stability was observed (25–350 °C); however, it demonstrated lower thermal conductivity (0.41 W/(m·K), 1200 °C) and maintained good high-temperature stability. The discovery highlights the promising practicality of both ceramics for high-temperature dielectric applications. [ABSTRACT FROM AUTHOR]

Borophosphosilicate glasses with varying sodium ion concentrations were investigated for their, structural, thermal, and electrical properties. All the obtained glasses were transparent except the glass with the highest sodium content, which exhibited translucency due to inhomogeneities. Increasing sodium content led to reduced boron and silicon content while maintaining a constant B/Si ratio, indicating progressive depolymerization of the glass network. Confocal microscopy, scanning electron microscopy, and atomic force microscopy showed homogeneous and granular structure for samples with lower sodium content, but higher sodium content resulted in visible agglomeration/nanocrystallization. X-ray diffractograms showed amorphous nature for most samples, with samples doped with the highest concentrations of Na 2 O showing several broad reflections suggesting nanoscale crystallinity. Fourier-transform infrared spectroscopy revealed shifts in dominant bands with increasing sodium content, indicating depolymerization of the borate network. An observed decrease in glass transition temperature and thermal stability with increasing sodium content was attributed to depolymerization and formation of non-bridging oxygens. Impedance spectroscopy revealed two relaxation processes associated with the transport of Na+ ions through two different regions. DC conductivity and activation energy predominantly increased with the sodium ion content at high temperatures. [ABSTRACT FROM AUTHOR]

Aluminum nitride (AlN), prized for its high thermal conductivity and electronic insulating properties, finds widespread use in electronic applications, particularly as a substrate material. However, its relatively low fracture toughness limits its application. In this study, to enhance both the thermal and mechanical properties of AlN ceramics, we thoroughly investigate the microstructure, thermal, and mechanical properties of self-reinforced AlN ceramics fabricated by spark plasma sintering, with self-reinforcement achieved through the integration of AlN whiskers within the AlN matrix. Unlike previous studies utilizing conventional pressureless sintering with limited sintering conditions, this work employs spark plasma sintering with a wide range of temperatures (1600–1900 °C) and holding times (10–30 min), providing a comprehensive understanding of the sintering behavior. Microstructural features, observed through optical and scanning electron microscopy, reveal distinct toughening mechanisms via crack deflection and branching, with a maximum 20% enhancement. The self-reinforced AlN ceramics exhibit remarkable improvements in thermal conductivity, reaching up to 150 W m−1 K−1, surpassing reported values for spark plasma-sintered AlN ceramics. Adding AlN whiskers enhances the thermal and mechanical properties of AlN simultaneously, particularly at 1800 °C for 10 min with controlled grain size and nicely integrated AlN whiskers. This work not only contributes valuable insights into the complex relationship between processing parameters, microstructure, and resulting thermal and mechanical properties but also highlights the enhanced thermal and mechanical properties of self-reinforced AlN ceramics. [ABSTRACT FROM AUTHOR]

Addressing the issue of carbon contamination during the smelting of specialty metals or alloys, utilizing graphite crucibles, has attracted considerable research attention, prompting the exploration of novel ceramic crucible materials. AlN ceramic, renowned for their exceptional high-temperature stability and resistance to corrosion, have emerged as promising candidates to mitigate this concern. Nonetheless, the limited mechanical properties and thermal shock resistance of AlN curtail its widespread application. In this study, Y 2 Zr 2 O 7 was introduced as an additive to enhance AlN's properties, and AlN-based composite ceramics were fabricated by employing pressureless sintering. The effects of Y 2 Zr 2 O 7 addition (3–10 wt%) on the mechanical properties and thermal shock resistance of the resulting composites were examined. The findings revealed that the incorporation of 5 wt% Y 2 Zr 2 O 7 (AlN-5YZO) led to the highest relative density and a refined grain structure, resulting in superior mechanical properties. Notably, the flexural strength, fracture toughness, and Vickers hardness of AlN-5YZO reached 322 MPa, 3.70 MPa m1/2, and 13.34 GPa, respectively. Furthermore, the presence of crack branching and crack deflection within the composite ceramics impeded crack propagation, effectively augmenting their thermal shock resistance. AlN-5YZO samples exhibited residual strength retention rates of 91.0 %, 84.2 %, and 76.7 % after 10, 20, and 50 thermal shocks between 1000 and 1600 °C, surpassing those of pure AlN. The findings of this study present promising avenues for advancing crucible materials tailored for high-temperature applications. [ABSTRACT FROM AUTHOR]