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In transportation applications, filling high pressurised hydrogen tanks within a few minutes implies a fast and large temperature increase that can compromise the structural integrity of the storage system and the safety of the process. Common approaches to control this temperature increase mainly involve hydrogen pre-cooling using complex and energy-demanding refrigeration systems. This study proposes and assesses alternative and energy efficient thermal management strategies for fast filling of hydrogen tanks including the modification of the liner's thermal properties and the use of existing on-board refrigeration systems. The analysis is performed by means of a Computational Fluid Dynamics model validated against experimental observations. Results show that proposed solutions provide a robust and efficient alternative to hydrogen pre-cooling, potentially simplifying the hydrogen supply system, reducing its associated energy demand, maintaining the hydrogen temperature below admissible limits and increasing the state of charge of the tank. • Strategies are based on liner pre-cooling and its thermal properties modification. • Similar H 2 temperature is achieved when pre-cooling it or changing liner properties. • Energy consumption of liner pre-cooling is up to 42–68% lower than H 2 pre-cooling. • Liner heat capacity increase is more effective than thermal conductivity increase. • Strategies increase the SOC up to 3.5% points compared to H 2 pre-cooling. [ABSTRACT FROM AUTHOR]

In this study, we designed four groups of A-substituted medium-entropy perovskites, synthesized (Ba 0.4 Sr 0.4 Ca 0.1 La 0.1)ZrO 3 , a non-equimolar medium-entropy perovskite, and studied its microstructural uniformity. The medium entropy of these perovskites imparts unique mechanical and thermal properties. Compared to pure BaZrO 3 , the cold moduli of rupture of the four samples improved by 164.29%, 121.22%, 91.49%, and 81.87%, respectively, and the relative density increased from 69.47% to over 90%. The thermal conductivities of these materials were lower than those of conventional low-thermal-conductivity perovskite materials, with a minimum value of 1.513 W/(m·K). The high strengths and low thermal conductivities of these novel perovskite materials could provide vast opportunities for various future applications. [ABSTRACT FROM AUTHOR]

Mullite fiber-based porous ceramics is one of the most commonly used high-temperature insulation materials. However, how to further reduce the thermal conductivity and improve the strength of such materials has been a challenge in the field of high-temperature insulation. In this paper, mullite micro/nano fiber-based porous ceramic was prepared by introducing mullite nanofibers into mullite microfiber-based porous ceramics and the effect of microfiber/nanofiber weight ratio on the samples properties were characterized and analyzed. Results showed that the compressive strength and high-temperature thermal insulation properties of the porous ceramics increased significantly with an increase in the nanofiber content. For the porous ceramics with similar density (about 0.50 g/cm3), the compressive strength of the sample with a microfibers/nanofibers weight ratio of 1:2 was 1.43 MPa, which was much higher than that of the porous ceramics prepared with only microfibers (0.26 MPa). Meanwhile, the backside thermal equilibrium temperature of the sample with a microfiber/nanofiber weight ratio of 1:2 at 900 °C environment was 355.8 °C, which was much lower than that of the porous ceramic prepared with only microfibers (476.5 °C). In addition, in order to investigate the temperature resistance of mullite micro/nano fiber-based porous ceramics, the sintering temperatures was increased from 1400 °C to 1500 °C. Results shows that the high-temperature thermal insulation performance of mullite micro/nano fiber-based porous ceramics with high mullite nanofiber content decays more seriously. The back-temperature test showed that the thermal equilibrium temperature of the samples with a mullite micron/nanofiber weight ratio of 1:1 in 900 °C environment increased rapidly from 386.3 °C to 454.2 °C when the sintering temperature was increased from 1400 °C to 1500 °C. The preparation of mullite micro/nanofiber-based porous ceramics provides a new strategy to improve the performance of fiber-based porous ceramics. [ABSTRACT FROM AUTHOR]

Dichromatic phosphor-in-glass films (PiFs) are recognized as ideal color converters for high-quality laser lighting, but photon reabsorption among multiple phosphor degrades the luminescence performance. Therefore, there is urgent to design a suitable PiF structure to alleviate this problem. Herein, the green-emitting phosphor YAGG:Ce and the orange-yellow-emitting phosphor GdYAG:Ce are mixed with silicate glass powder respectively, and print on the sapphire plate with high thermal conductivity (TC) to prepare spatially separated structure PiF (SS-YG PiF). Under the excitation of blue LD with power of 6.15 W, the luminous flux (LF) of SS-YG PiF reaches 1020.4 lm, and the corresponding luminous efficiency (LE) reaches 165.92 lm/W and CRI∼80. Notably, the perfect white light color coordinates (0.3354, 0.3253) are obtained at 6.15 W. In addition, SS-YG PiF has a lower surface temperature and a higher TC (9.89 W m−1K−1), reflecting the excellent luminescence performance and thermal properties of SS-YG PiF. [ABSTRACT FROM AUTHOR]

Ni-containing SiOC bulk ceramics have been prepared by spark plasma sintering at 1300 °C from polysiloxane at Ar atmosphere in the present work. The microstructure and properties of SiOC ceramics with different Ni content were studied. The resultant Ni-containing SiOC ceramics consists of in situ formed turbostractic layer carbon, CNTs (C nanotubes) and SiC crystals which dispersed in the SiOC matrix. With increasing content of Ni, the Ni-containing SiOC ceramics displayed less porosity. And the increasing Ni improved the mechanical, thermal and friction properties of SiOC ceramics. Ni-containing SiOC ceramics developed a carbon friction layer, which enhanced abrasion resistance to provide friction materials with stable friction coefficients and low abrasion values. A decrease in wear mass, from 2.06 to 0.18 mg was observed as the Ni content increasing from 0 to 2 wt%. The primary wear mechanisms of SiOC ceramics were recognized as abrasive wear, fatigue wear, and adhesion wear. [ABSTRACT FROM AUTHOR]

Entropy plays a crucial role in designing new functional materials or enhancing material performance. The design of high entropy ceramics (HECs) introduces a larger composition space, thus the understanding of the correlation between the composition, entropy effect, and the performance of HECs is becoming increasingly important. In this work, to pursue superior properties, a series of CeNbO 4 -based solid solution ceramics with a maximum of 9 species cations in a single sublattice were synthesized by using high entropy configuration strategy. The interaction of composition, size disorder, and configurational entropy on the properties of HECs was emphasized. The potential conflict between high resistivity and low material constant of thermosensitive ceramics was overcome and thus achieving excellent thermal sensitivity properties having an extremely wide temperature range from room temperature to 1623 K and long-term high-temperature stability. This will bring innovative prospects for the design and application of high-temperature functional ceramics. [ABSTRACT FROM AUTHOR]

In this work, the influence of AlN particle size (250 nm, 1.2 µm, and 5 µm) on the curing behavior, stability and viscosity of ceramic suspensions was evaluated. It was revealed that an increase in the particle size of AlN powders reduced the stability and viscosity of the suspension. For curing behavior, the ceramic suspension prepared with 250 nm AlN powder exhibited the smallest curing depth and excess width, whereas the 5-μm ceramic suspension had the largest curing depth. The analysis of the scattering length revealed that a decrease in AlN powder particle size reduced the scattering length. After sintering, both the 250-nm and 1.2-μm samples could be sintered densely at temperatures more than 1800 °C with the relative density greater than 99%. Finally, following a 5 h sintering at 1850 °C, the 250-nm and 1.2-μm samples obtained thermal conductivities of 171 and 174 W/mK, respectively. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the impact of polysaccharide type on the physicochemical, structural, and thermal properties of dielectric barrier discharge (DBD) plasma glycosylated sodium caseinate (SC). The polysaccharides Quince seed gum (QSG), carboxymethyl cellulose (CMC), and maltodextrin (MD) were mixed with SC and treated with DBD plasma at 18 kV for 10 min. The grafting degree, electrophoresis pattern, FTIR, XRD, carbonyl, sulfhydryl, and di-tyrosine content, FE-SEM, color, and thermal properties of SC and its polysaccharide mixtures before and after plasma treatment were analyzed. Results showed that the SC-QSG conjugate had the highest glycation degree and color change after plasma treatment. The SC-CMC and SC-QSG conjugates exhibited disappearance of distinct SC bands in electrophoresis pattern compared to SC. Also, significant changes in functional group and crystallinity were occurred in SC-CMC conjugate. Plasma treatment caused oxidation of SC, but the presence of polysaccharides offered protection against oxidation. The microstructure of SC was altered by mixing with polysaccharides and exposure to plasma. Also, the mixtures indicated higher thermal stability after plasma treatment. Results confirmed that the generation of protein-polysaccharide conjugates through DBD plasma technique was depended on with SC-MD conjugate unable to form through this method. [ABSTRACT FROM AUTHOR]

This comprehensive research explores the starch isolated from four browntop millet cultivars to determine physicochemical, thermal, morphological, powder flow, pasting, and rheological properties. Significant variations (p ≤ 0.05) were observed among the cultivars. Aerated bulk density (ABD) and Tapped bulk density (TBD) values ranged from 0.476 g/mL (BTM4) to 0.591 g/mL (BTM1), and 0.591 g/mL (BTM1) to 0.476 g/mL (BTM4). Amylose content varied from 22.55% (BTM4) to 25.86% (BTM3), influencing gelling strength and film-forming properties. Water absorption capacity ranged from 1.78 g/g to 1.92 g/g, while oil absorption capacity varied from 2.20 g/g to 2.47 g/g. DSC analysis showed gelatinization temperatures (Tp, and Tc) ranging from 85.44–91.61 °C, and 147.08–154.21 °C, respectively. X-ray diffraction (XRD) patterns revealed A-type crystalline patterns, with relative crystallinity ranging from 22.66% (BTM3) to 27.81% (BTM2). Pasting properties exhibited variations among cultivars, with peak viscosity ranging from 2480 c P to 3119 cP, and pasting temperature from 77.50 °C to 82.35 °C. Rheological analysis indicated shear-thinning behavior. The findings offer insights into the diverse properties of browntop millet starch, contributing to its potential applications in various industries and potentially guiding future studies on browntop millet starch modifications and novel utilization. [ABSTRACT FROM AUTHOR]

Fiber-reinforced biocomposites were widely considered as the optimal sustainable alternative to traditional petroleum-based polymers due to their renewable, degradable, and environmentally friendly characteristics, along with economic benefits. However, the poor interfacial bonding between the matrix and natural fiber reinforcement remained a key issue limiting their mechanical and thermal properties. Focusing on cost-effective, convenient, and low-pollution chemical methods, this work proposed a strategy for in-situ synthesis of composite structures on bamboo fiber (BF) surfaces. Crude chitosan (CS) and reclaimed tannic acid (TA) were utilized as the raw materials, to construct stereo-netlike chitosan @ tannin structures (CS@TA) via a one-pot method facilitated by hydrogen bonding and complexation. The influence of reactant concentration and pH value on the process was further investigated and optimized. The CS@TA structure improved the interfacial bonding between the BF reinforcement and matrix poly(3-hydroxybutyrate) (PHB), and this non-amino-driven construction provided a potential reaction platform for functionalizing the interfacial layer. The modified biocomposite showed improvements in tensile and impact strengths (51.58 %, 41.18 %), also in tensile and flexural moduli (13.59 %, 26.88 %). Enhancements were also observed in thermal properties and heat capacity. This work presents a simple and promising approach to increase biocomposite interface bonding. [Display omitted] • CS@TA structures were respectively constructed in situ and in vitro. • Effects of varying reactant concentrations and pH values were investigated • Morphology and crystallinity of the BFs were modified. • Mechanical and thermal properties of the biocomposites were enhanced. [ABSTRACT FROM AUTHOR]

Cellulose, as a biomass resource, has attracted increasingly attention and extensive research by virtue of its widely sources, ideal degradability, good mechanical properties and easy modification due to its rich hydroxyl groups. Nevertheless, it is still a challenge to attain high performance cellulose-based composite film materials with diverse functional combinations. In this work, we developed a multifunctional cellulose-based film via a facile impregnation-curing strategy. Here, benzoxazine resin (BR) is used as an optically functional component to endow the microfibrillated cellulose (MFC) film with powerful light management capabilities including UV and blue light double shielding, high transmittance, and high haze. Meanwhile, the introduction of tannic acid (TA) substantially enhanced the mechanical properties of the film, including tensile strength and toughness, by constructing energy-sacrificial bonds. An effective self-healing of the film was achieved by controlling the degree of BR curing. The final films exhibited 98.24 % UV shielding and 89.98 % blue light blocking, good mechanical properties including a tensile strength of 202.21 MPa and tensile strain of 7.1 %, as well as desirable thermal healing properties supported by incompletely cured BR. This work may provide new insights into the high-value utilization of biomass resources. [ABSTRACT FROM AUTHOR]

Core-shell structured copper-boron nitride (Cu@BN) spherical fillers were synthesized to fabricate thermally conductive composites. To enhance the interaction between the fillers and the matrix, polysilazane (PSZ) was coated on the surface of the filler. The resultant composite exhibited remarkable characteristics, including a substantial tensile strength of 32.36 MPa, excellent electrical insulation properties, and impressive thermal conductivity of 3.47 W/mK. When applied in a light-emitting diode (LED) application, the composite effectively managed heat, reducing the operating temperature by 34 °C. The epoxy/PSZ-Cu@BN composites hold great promise for improving thermal management in electronic devices. • The copper-boron nitride (CuBN) core-shell structured filler was fabricated. • The PSZ coating of CuBN reinforced thermal and mechanical properties of composites. • The Epoxy/PSZ-CuBN composites achieved high thermal management performance. [ABSTRACT FROM AUTHOR]

In this study, SiCp-SiO 2 /6061Al composites were synthesized by integrating SiC and SiO 2 particulates into a 6061Al matrix, followed by ball milling and hot isostatic pressing sintering. The impact of ball milling duration on microstructure, mechanical properties, corrosion resistance, and thermal properties was evaluated. After 10 h of ball milling, reinforcement particles were uniformly dispersed, achieving a material density of over 98 %. Extending milling to 15 h enhanced tensile strength to 253.53 MPa and flexural strength to 433.56 MPa, with a maximum elongation at break of 6.4 %. Uniform SiO 2 distribution improved corrosion resistance, evidenced by a self-corrosion potential of −1209 mV and a self-corrosion current density of 53.02 µA·cm−2. After 20 h, the lowest thermal expansion coefficient, 19.87×10−6·K−1, was achieved. However, agglomerated particles after 5 h resulted in inferior thermal properties, including a thermal expansion coefficient of 20.45×10−6·K−1 and thermal conductivity of 94 W·m−1·K−1. The optimal ball milling duration for these composites was determined to be 10 h, balancing performance and cost-effectiveness. • High Performance and Versatility: The composite material exhibits excellent mechanical strength and ductility, with enhanced thermal stability. After 15h of ball milling, it achieved a tensile strength of 253.53 MPa and an elongation at break of 6.4 %, with an average thermal expansion coefficient of 20.26×10−6·K−1 between 25 and 300℃. These properties make it ideal for applications in the aerospace, automotive, and electronics industries. • Enhanced Corrosion Resistance: Uniform SiO 2 distribution after 15 h ball milling significantly enhances corrosion resistance. • Optimized Thermophysical Properties: SiO 2 reinforcements reduce thermal expansion coefficient and enhance the stability of composites; milling time also impacts thermal properties. [ABSTRACT FROM AUTHOR]

Phase change materials (PCM) have attracted much attention in the field of thermal energy storage because of exceptional heat storage capacity, stable operating temperature, and recyclability. However, organic phase change materials, represented by palmitic acid (PA), are limited by inherent leakage problem, unsatisfactory thermal responsiveness and inefficient photo-thermal storage capacity, which severely hamper the development of PCMs technology. As a means of addressing these challenges, we developed one novel support material with 2D/0D structure for palmitic acid via thermal polymerization, specifically, in which highly dispersed Ag quantum dots (Ag QDs) was firmly anchored on graphitic carbon nitride (g-C 3 N 4). PA was further infiltrated into the layered structure of nanoporous g-C 3 N 4 /Ag QDs to successfully synthesize novel shape-stabilized PA/g-C 3 N 4 /Ag QDs composite phase change materials (CPCM). On the one hand, benefiting from the tightly stacked porous structure of g-C 3 N 4 /Ag QDs, PA is effectively encapsulated to avoid leakage problem during the solid-liquid transition with a superior adsorption capacity up to 65 %. On the other hand, the combination of g-C 3 N 4 and Ag QDs in PA/g-C 3 N 4 /Ag QDs CPCM demonstrated a synergistic effect resulting in faster heat transfer capability and more efficient solar energy capture capability compared to pure PA, which is capable of dual utilization of heat and solar energy. The newly developed PA/g-C 3 N 4 /Ag QDs CPCM features a high melting latent heat and an appropriate phase change temperature, which are 128.35 J/g and 61.92 °C, respectively. The corresponding solidification enthalpy and temperature are 121.70 J/g and 60.02 °C. The photo-thermal conversion efficiency of the material is improved to 78.6 %, facilitating a rapid capture and storage of solar energy. Furthermore, through the optimization of the preparation process, Ag QDs are densely anchored on the surface of g-C 3 N 4 , which retains the excellent properties of metallic silver while eliminates the metal agglomeration phenomenon after repeated utilization of CPCMs. PA/g-C 3 N 4 /Ag QDs CPCM is proved to be extremely recyclable and thermally stable after massive thermal cycles. This innovative and operational encapsulation modified method significantly optimizes the practicality of phase change materials. The obtained shape-stabilized PA/g-C 3 N 4 /Ag QDs CPCM is more versatile, and its unique comprehensive properties can provide high-quality materials for photo-thermal storage systems. • 2D/0D structure g-C 3 N 4 /Ag QDs are constructed to encapsulate PA. • Novel PA/g-C 3 N 4/ Ag QDs CPCM is developed with outstanding and stable thermochemical properties. • PA/g-C 3 N 4 /Ag QDs CPCM exhibits stronger photo-capture capability with increased photo-thermal conversion efficiency of 78.6 %. • By the optimized synthesis process, CPCM has outstanding shape and structural stability to overcome metal agglomeration. [ABSTRACT FROM AUTHOR]

The development of photoresponsive shape memory materials based on the photothermal conversion properties of lignin and the low activation energy of the dynamic covalent borate bond is of great importance. In this paper, a kind of lignin-based vitrimer polymer (LBP) containing dynamic boronic ester bonds was prepared by a "sulfhydryl-epoxy" click reaction and etherification reaction. The results show that the rigid segment EP-EL (lignin-based epoxy resin) and BDB (2,2′-(1,4-phenylene)-bis-[4-mercapto-1,3,2-dioxaneborane]) with benzene ring structure can impart tensile strength (20.8 MPa) to the LBP, while the flexible segment PEG imparts good elongation at break (15 %). The dynamic binding and dissociation exchange mechanism of the boronic ester bonds enables LBP to exhibit thermal remodelling properties (up to 36.2 %) and water-assisted self-healing properties at room temperature (up to 49.0 %). In addition, LBP exhibits excellent thermal and light-responsive shape memory properties due to its own photothermal conversion performance (photothermal conversion efficiency up to 18.2 %) and the dynamic boronic ester bond thermal activation bond exchange mechanism. The insulating properties of LBP make it suitable for use in high temperature protection circuit devices and light-responsive circuit devices. This study provides new insights into the design and application of Vitrimer and photoresponsive shape memory polymers, and also offers a new avenue for high-value utilization of lignin. [Display omitted] • Combining the low activation energy of boronic ester bonds with the photothermal properties of lignin • Solar responsive shape memory material based on lignin produced for the first time • LBP is applied to high temperature protection circuit devices and light response circuit devices. [ABSTRACT FROM AUTHOR]

This study thoroughly examines the structure, mechanical properties and thermal stability of ZrN coating with oxygen modification. Incorporation of oxygen atoms initiates a structural transformation from fcc-ZrN to fcc-Zr(O)N solid-solution, followed by a mixed state comprising primarily fcc-Zr(O)N solid solution alongside a minor ZrO 2 oxide phase, ultimately forming a pure ZrO 2 coating. This structural transition induces initially an increment in hardness from ∼23.5 GPa of Zr(O 0.02 N 0.98) 0.96 to ∼31.7 GPa of Zr(O 0.17 N 0.83) 1.08 due to solid solution strengthening effect, but a subsequent reduction was noted as a result of the increment in ionic bonds and the formation of oxide phase. Remarkably, optimal oxygen levels (10 and 17 at.%) were found to enhance fracture toughness within cubic coatings, which were validated by combined experimental and DFT analyses, showcasing the nuanced influence of oxygen content on mechanical properties. Following thermal annealing, Zr-O-N coatings exhibited a systematic decomposition with the occurrence of ZrO 2 oxide phase in contrast to the stable ZrN coating. • Oxygen incorporation forms c-Zr(O)N prior to c-ZrN transforming into pure ZrO 2. • Moderate oxygen introduction enhances the intrinsic toughness of ZrN coating. • Formation of various ZrO 2 phase accelerates the decomposition of Zr-O-N coatings. [ABSTRACT FROM AUTHOR]

With the widespread application of carbon fiber reinforced polymer (CFRP) in engineering, the characteristics of uniformly carbon fiber (CF) orientation within a single-ply and laminated structure have inspired us to develop high-efficiency, low-consumption, manufacture-friendly, and non-destructive anti-icing/de-icing methods. Here, we propose a CFRP surface ply-centric electrified spatiotemporal self-heating (STSH) approach, which utilizes CFs in the surface ply as natural heating elements to achieve in-situ adaptable electrothermal anti-icing/de-icing. By adjusting the current waveform, the temporal heating profile can flexibly switch between a consistently stable temperature and periodically high peak temperatures, meeting the different heating characteristics required for anti-icing and de-icing, respectively. Simultaneously, the entangled CFs branch current, generating a spatial temperature gradient that enhances the design flexibility of temperature distribution. This enables energy concentration in icing-prone areas while maintaining a baseline temperature in less susceptible areas, thus reducing energy waste by up to 20%. Overall, this STSH approach is simple, efficient, and holds significant application potential, offering an innovative and feasible solution to long-standing challenges associated with anti-icing/de-icing. [Display omitted] • Simple and efficient solution to CFRP icing problems in extreme environments. • Without altering the manufacturing process and incurring additional costs. • With no introduction of heterogeneous elements, preserving mechanical integrity. • Imparts anti-icing/de-icing capabilities requiring only minor sanding. [ABSTRACT FROM AUTHOR]

The development of multifunctional electromagnetic interference (EMI) shielding materials has garnered significant attention, yet achieving flexible composites that integrate EMI shielding, thermal conductivity, and other functionalities under low filler loading remains a challenge. This study presents a novel flexible composite with segregated structure prepared via a simple co-mixing and hot-pressing method. By selectively distributing conductive Liquid metal (LM) and Multi-wall carbon nanotube (CNT) on the surface of Polyurethane (TPU) particles, a continuous and compact conductive network is successfully constructed, enabling the attainment of a high EMI shielding effectiveness of 80.2 dB and a thermal conductivity of 4.8 W m−1 K−1 even at low LM loadings. Furthermore, the composite exhibits low-voltage-driven Joule heating performance, excellent photothermal conversion efficiency, and promising potential for wearable sensor applications. The combination of these outstanding properties highlights the great potential of LM-based composites for next-generation wearable devices. Multifunctional TLMC composites that integrate EMI shielding, thermal conduction, strain sensing, and photothermal conversion properties. [Display omitted] • TLMC flexible composite with segregated LM/CNT structure. • Remarkable photothermal and electrical-to-thermal conversion capabilities. • Excellent conductivity (100.2 S/cm) and superior EMI SE (up to 80.2 dB). • Strain sensing application capable of monitoring wearable motion. [ABSTRACT FROM AUTHOR]

Of large length-to-diameter ratio and specific area, inorganic whiskers were widely applied for polymer reinforcement. As a well-known nanofiller, titanium dioxide (TiO 2) has been welcome by polymer engineering, mostly for whitening with spherical shapes favored. To date, there have been no TiO 2 whiskers reported for polymer reinforcement. In this work, a rutile type TiO 2 whisker was compounded with polyamide 66 (PA66) to prepare nanocomposites with surficial modification being conducted to further improve the compatibility between them. It was found that the rutile-type TiO 2 whisker significantly improves the mechanical properties of PA66 at high loadings and the performance went better when surficial modification for it was applied. Under 50 wt% addition of TiO 2 whisker either modified or not, the tensile strength, tensile modulus, flexural strength, flexural modulus, impact strength and heat deformation temperature of prepared PA66 composites were respectively increased by 52 %, 279 %, 44 %, 313 %, 20 %, 199 % and 84 %, 279 %, 88 %, 303 %, 114 %, 207 %, comparing with the pristine PA66. The mechanism regarding the overall reinforcement was analyzed, which was attributed to the shape-relevant multiple interactions between TiO 2 and PA66. Besides, the improved adhesion due to strong stable chemical bonding by surficial modification of fillers, is also accountable. [Display omitted] [ABSTRACT FROM AUTHOR]

Conducting biopolymer blend nanocomposites of cashew gum (CG) and polypyrrole (PPy), with varying concentrations of copper oxide (CuO) nanoparticles were synthesized through an in-situ polymerization method using water as a sustainable solvent. The formation of blend nanocomposites was characterized using UV–visible (UV–vis) spectroscopy, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). UV spectroscopy revealed a significant reduction in absorption intensity with the addition of CuO, indicating enhanced optical properties. FT-IR and XRD analysis confirmed the successful incorporation of CuO into the CG/PPy blend. FE-SEM images revealed the uniform distribution of nanoparticles throughout the biopolymer blend, particularly in the 7 wt% sample. TGA and DSC results demonstrated a significant enhancement in thermal stability, increasing from 352 °C to 412 °C and a rise in the glass transition temperature from 89 °C to 106 °C in the blend nanocomposites. The dielectric constant, dielectric loss, impedance, Nyquist plot, electrical conductivity, and electric modulus were extensively examined at different temperatures and frequencies. The dielectric constant of the CG/PPy blend increased from 2720 to 92,950 with the addition of 7 wt% CuO, measured at 100 Hz. The improved glass transition temperature, thermal stability, and superior electrical properties imply potential usage of the developed nanocomposite in nanoelectronics and energy storage applications. • Ecofriendly synthesis of cashew gum (CG)/polypyrrole (PPy)/copper oxide (CuO) biopolymer blend nanocomposites. • Enhancement in optical, structural, and thermal properties of CG/PPy/CuO. • Temperature and frequency dependence of AC electrical conductivity and dielectric properties are summarized. • Blend nanocomposite shows higher AC conductivity and dielectric constant. • These blend nanocomposites are suitable for energy storage applications. [ABSTRACT FROM AUTHOR]

Building and construction waste contributes to global carbon emissions, leading to the need to seek alternative materials that are more environmentally friendly. Mycelium Biocomposite (MB) is a sustainable material that utilizes agricultural waste as its main substrate and can be degraded after-use. This study aimed to investigate mechanical performance of additional layers in sandwich panel fabrication of MB. The experiment was conducted in two phases including (1) Composite 1: Oil Palm Empty Fruit Bunch (OPEFB) fiber layer with pine resin and (2) Composite 2: MB sandwich panel. In Composite 1, the mechanical test results showed the S50 sample (50 % fiber and 50 % resin) had the highest tensile strength of 0.18 N/mm² and was selected as the surface layer. In Composite 2, the variable of layer binder was produced using mycelium hyphae (MB-M) and resin (MB-R). The results of the physical, mechanical, and thermal properties tests were compared with the JIS A 5905:2003 standard and previous studies. The MB sample (no layer) had the best mechanical and thermal conductivity values due to the binding method effects, such as flexural strength at 25.38 N/mm² and bending strength at 0.53 N/mm². MB-M showed incomplete drying that caused lower tensile strength and higher thermal conductivity. Meanwhile, MB-R showed mechanical values similar to MB, such as flexural strength at 21.22 N/mm² and bending strength at 0.52 N/mm². Yet, MB had higher thermal conductivity, where MB-R showed 0.1558 W/mK and MB showed 0.1037 W/mK, due to Composite 1 addition. This study suggests the development of MB thermal values and considers its application as non-structural insulation panels. • Sustainable alternative material: Mycelium Biocomposite (MB) with additional layer in sandwich panel fabrication. • Oil Palm Empty Fruit Bunch (OPEFB) with pine sap bioresin binder as additional layer. • Investigating physical, mechanical and thermal properties of Mycelium Biocomposite (MB). • Mycelium Biocomposite (MB) sample with no additional layer has a high mechanical and thermal conductivity value. • MBs exhibit potential as renewable materials and alternative insulation panels for non-structural insulation panels. [ABSTRACT FROM AUTHOR]

[Display omitted] • High-performance m -aramid copolymers containing p -aramid side chains were obtained. • The aramid lateral chains were terminated with nitro groups. • Copolymers resulted in a 48% increase in the Young's modulus compared to MPIA. • The performance of the new copolymers improved in upon exposure to hydrogen. • They can be applied as steel coatings in high-pressure hydrogen storage. This study aimed to enhance the mechanical properties of m -aramids by incorporating varying percentages of p -aramid side chains through copolymerization while ensuring solubility for practical applications. The mechanical performance of the resulting copolymers was compared with the commercial m -aramid, MPIA (poly(m -phenylene terephthalamide)). Notably, even with a 20% incorporation of p -aramid side chains, there was a substantial increase of 48% in Young's modulus and 7% in tensile strength compared to MPIA. Additionally, the nitro group capping the p -aramid side chains demonstrated significant efficacy in enhancing the mechanical performance of the materials upon exposure to hydrogen. Specifically, there was an increase of more than 11% in Young's modulus upon initial contact with hydrogen. This finding suggests potential applications in protective coatings for stainless steel used in high-pressure hydrogen storage environments. In such applications, exposure to hydrogen can accelerate embrittlement and limit operational lifespan, and coating with these materials can mitigate embrittlement and improve operational lifespan. [ABSTRACT FROM AUTHOR]

Systematization and analysis of standalone waste materials that can serve as phase change materials (PCMs), and composites consisting of commercially available PCMs combined with organic and inorganic waste materials is presented. Within the conducted review research, obtained thermal properties of so far investigated waste-derived PCMs were presented, assessing, among other, their latent heat storage capacity, thermal conductivity, and thermal and cyclic stability. Refined coconut oil and Allanblackia oil exhibited exceptional thermal and cyclic stability along with high values of latent heat, amounting 105 kJ kg−1 and 81 kJ kg−1, respectively. In some cases incorporation of waste materials significantly improved thermal properties, e.g. the addition of carbonized waste tire rubber to dodecyl alcohol increased its thermal conductivity to 0.431 W m−1K−1, representing an increase by a factor of 2.3. This enhancement led to a 17.2 % reduction in heating times and a 20 % reduction in cooling times compared to using pure PCM. Besides providing extensive data on thermophysical properties of phase change composites, the study provides a comprehensive overview of their applications, economic feasibility, and environmental implications. This extensive review shows the potential of waste-derived PCMs to contribute to a circular economy by repurposing waste materials for sustainable energy solutions and reducing environmental impacts. The findings indicate that while valorising wastes or by-products as latent thermal energy storage materials is feasible, more research efforts are required towards potential commercialization. • Valorisation of waste materials for LTES (Latent Thermal Energy Storage) applications. • Categorized and analysed applications of waste in LTES systems. • Summarized thermal properties of waste-based phase change materials (PCMs). • Economic and environmental aspects of waste-based PCM discussed. • Future directions for usage of waste-based PCMs in LTES elaborated. [ABSTRACT FROM AUTHOR]

• The vertical Bridgman method was first used to grow large-sized La 3 Ga 5.5 Nb 0.5 O 14 (LGN). • LGN crystal has wide transmittance range and high transmittance up to 80%. • LGN crystal possesses wide band gap of 4.16 eV and large laser damage threshold of 1.416 GW/cm2. • LGN crystal has stable thermal properties which is suitable for high energy laser applications. La 3 Ga 5.5 Nb 0.5 O 14 (LGN) crystal is a promising material for optical parametric chirped-pulse amplification (OPCPA) with high laser damage threshold and wide transmission range which is able to achieve high peak power laser. LGN with a diameter of 25 mm was successfully grown by the vertical Bridgman method for the first time and a series of characterizations were performed. The 1.7 µm absorption peak in transmittance spectra of LGN crystal which was caused by the Czochralski technique can be effectively eliminated by the vertical Bridgman method. LGN crystal possesses a high transmittance of 81.3 % in the range of 0.294 ∼ 7.500 μm. The experimental optical band gap of LGN is 4.16 eV which is positively correlated with laser damage threshold. The experimental laser damage threshold of LGN was determined to 1.416 GW/cm2 by Nd:YAG. The outstanding thermal properties of LGN indicate that it possesses thermal stability in high energy laser field. This work demonstrates that LGN crystal holds great potential for OPCPA applications and the vertical Bridgman method is proved to be a effective and excellent technique to grow high quality LGN crystal. [ABSTRACT FROM AUTHOR]

• A novel geopolymer concrete is developed incorporating waste ceramic aggregates. • The designed geopolymer exhibit ultra-high residual strength after 1000 ℃ thermal exposure. • The high temperature resistance and mechanism of designed geopolymer are investigated. A novel geopolymer concrete is developed, incorporating waste ceramic aggregates, with ultra-high residual strength after exposure to elevated temperatures. Different aggregate volume fractions and particle size gradations are designed, and the variations in mass loss, volume shrinkage, compressive strength, mineral composition, and microstructure of geopolymer mortar after exposure to high temperatures ranging from 20 ℃ to 1000 ℃ are investigated by testing mass loss, volume change, strength, XRD and SEM. The results show that the waste ceramic aggregates (WCA) applied in the preparation of geopolymer mortars improve the mechanical properties and high-temperature resistance. By optimizing aggregate particle size gradation, the microstructure of the geopolymer mortar becomes denser and more homogeneous, and the high-temperature resistance is further improved. The residual compressive strength at 1000 °C is 115.2 MPa, 476 % higher than that of reference. These findings demonstrate the great potential of geopolymer mortars using ceramic aggregates with optimized gradation for high temperature resistant applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Facile synthesis of eco-friendly wheat husk biomass derived microparticle. • Maximum thermal conductivity increments of the A-70 + WH composite is 66.66 %. • Heating enthalpy increment of WH derived PCM composite is 4.57 %. • Proven thermal reliability of A-70 + WH composite for 500 thermal cycles. Organic phase change materials (PCM) exhibit poor volumetric latent heat storage capacity and have low thermal conductivity. Therefore, this study aims to develop a PCM composite with better thermal conductivity and latent heat by dispersing newly synthesized wheat husk microparticles in Paraffin wax (A-70) PCM via a two-step technique. As per the results, the developed composite materials latent heat and thermal conductivity were 217.1 J/g & 0.45 W/m K, which was 4.57 % and 66.66 % higher than base PCM, respectively. Moreover, after 500 thermal cycles, the newly synthesized composite was found to be thermally and chemically stable. [ABSTRACT FROM AUTHOR]

Transparent bamboo proved to be a promising substitute for glass due to its high light transmittance and excellent mechanical properties. Nevertheless, it was susceptible to outdoor weathering, which negatively affected its physical and mechanical properties. In this study, two decolorisation methods, namely the delignification method and the lignin modification method, were used to produce transparent bamboos with epoxy resin, referred to as DL-TB and LM-TB, respectively. The changes in surface color, optical and mechanical properties, wettability, thermal stability, and thermal insulation properties of transparent bamboo during accelerated UV weathering were evaluated. Additionally, the deterioration mechanism of DL-TB and LM-TB was investigated. The findings revealed that DL-TB demonstrated better transparency and mechanical properties than LM-TB, although it exhibited lower thermal insulation properties. Furthermore, DL-TB demonstrated enhanced color stability and higher hydrophobicity on weathered surfaces than LM-TB. Unexpectedly, the tensile properties of both two transparent bamboos significantly improved after weathering, especially for LM-TB, which was due to the EP post-curing and the formation of more hydrogen bonds between lignin and EP. These observations revealed that lignin played a key role in the photodegradation process of transparent bamboo, but further attempts should be made in future studies to improve its color stability. [Display omitted] • Transparent bamboo was prepared through two decolorisation methods. • The weatherability of transparent bamboo during weathering was studied. • Transparent bamboo without less lignin showed better color stability. • Lignin in transparent bamboo was beneficial for thermal and mechanical properties. [ABSTRACT FROM AUTHOR]

The effects of high-temperature storage at 37 °C on the crystallinity, pasting, rheological, and thermal properties of adlay seed starches from three famous Chinese varieties were studied. The results showed that high-temperature storage altered the natural structure of adlay seed starch, resulting in increased peak viscosity for all starch pastes after one month of storage at 37 °C. Jinsha adlay seed starch (JSC), which had the highest amylose content (11.21 %), showed increased D 50, relative crystallinity and OD values, demonstrating strong regrowth ability and hydrophobicity, with starch gels having greater hardness and gumminess after storage. In contrast, Pucheng adlay seed starch (PSC) and waxy Ninghua adlay seed starch (WSC), with similar amylose proportions, showed distinct starch gel properties. PSC (with an amylose content of 3.35 %) exhibited better starch gel properties, whereas WSC (amylose content of 5.74 %) demonstrated improved gumminess and chewiness after storage and exhibited stronger anti-starch regrowth capabilities. This study provides valuable insights into the selection of future starches based on their specific processing requirements. [Display omitted] • Three regional sources of adlay seed starch in China were analyzed. • The edible quality of adlay seed starch is best in Pucheng. • The storage had effect on the crystal structure. • The initial content of amylose was not affecting storage quality for starch. [ABSTRACT FROM AUTHOR]

The novel multi-stage method for preparation of especially pure Ge x As y Sb z S 100-x-y-z (x = 10–13; y = 20–23; z = 4–6) glasses is presented. The method includes the stages of deep purification of initial elements using different chemical getters, transport reactions and vacuum distillation. The glass samples with compositions close to stoichiometric ones and a low content of gas-forming impurities are synthesized; their structure, optical, thermal and magneto-optical properties are investigated. The studied characteristics of the samples meet the requirements for their use in the IR optics and are relevant for multifunctional applications. [ABSTRACT FROM AUTHOR]

In the present study, tellurium-rich (45–55 mol%) As-Se-Te chalcogenide glasses were synthesized and purified further to eliminate the impurities for achieving extended far infrared transmission. The glasses were characterized and studied for physical, thermal, optical, structural and mechanical properties. All the glasses have shown transparency in the wavelength range of ∼1.6–19 µm, with >45 % transmission with impurities. The purification process through vacuum distillation has eliminated the oxide impurities in the glass and the glass displayed ∼52 %T in the wide infrared region. The refractive index for purified glass decreased from 3.487 at 2 µm to 3.362 at 10 µm. The purified glass was heat treated for four hours, and the most dominant crystal phase, As 2 Te 3 was observed in XRD analysis. Presence of sharp Raman peak at ∼120 cm−1 belonging to As 2 Te 3 pyramids in heat-treated sample well agreed with the XRD results. [ABSTRACT FROM AUTHOR]

• The method of in-situ melt pool control was proposed. • A mathematical model of the heat accumulation effect was derived. • The effect of in-situ melt pool control on forming quality was determined. • The influence of cooling rate on the microstructure evolution was revealed. • The rules of plastic deformation induced by twins were investigated. Thin-walled aerospace components manufactured by laser directed energy deposition are susceptible to thermal accumulation effects owing to their deposition path and efficiency, further leading to the edge collapse. The melt pool width, as the carrier of thermal input, is an important geometric factor reflecting the state of the melt pool. Therefore, an in-situ melt pool control technique was proposed. The melt pool width as the control target was monitored using a coaxial camera, and the laser power was adjusted in real time based on the proportional-integral-derivative algorithm. A thermal accumulation model in conventional mode and a thermal suppression model in control mode were derived. The surface roughness, porosity, microstructure, and tensile properties of AISI 316 L stainless steel were compared between two modes. The results demonstrated that the roughness and porosity of thin-walled parts were respectively reduced by 45.3% and 82.7% after control. The periodic evolution of interlayer columnar and equiaxed crystals, and the increase in deformation twins contributed to a simultaneous increase in tensile strength and toughness, with a maximum increase of 35.7% in elongation. [Display omitted] [ABSTRACT FROM AUTHOR]

To design such a hybrid battery thermal management system (BTMS), it is crucial to establish a practical and realistic approach from the point of view of: i. simulated operating conditions, ii. assumed materials/compounds, iii. Fast-charging performance test. To avoid oversizing, this work considers the World Harmonized Light-duty Vehicle Test Procedure Class 3 (WLTP3) driving cycle, instead of constant charge/discharge rates. Power requirements of a medium-sized vehicle during this WLTP3 cycle have been used to estimate the heat generated by the proposed battery module (18650 NMC cylindrical cells, hexagonal arrangement). This allows the minimum mass required by the phase change materials (PCM) to maintain the battery module at a given temperature threshold to be determined. Once this PCM mass requirement was established, a comprehensive optimization of the key thermal properties that characterize PCMs was carried out, investigating carbon-based additives (CBAs) to improve the low thermal conductivity of PCMs. The results show that the proposed approach can sustain up to 10 consecutive WLTP3 driving profiles without the need for additional energy input. This approach passively minimizes energy consumption during operation and absorbs up to 27 % of the heat emitted by the cell during fast charging, reducing the liquid cooling power requirement. • A hybrid BTMS composed of ssPCMs and liquid cooling is optimized. • WLTP3 drive cycle used instead of constant rates are used to size PCM thickness. • Hexagonal cell arrangement ensures minimum space use in battery packs. • Optimal properties: Cp eff ∼85 kJ/(kg·K) and k eff ∼8 W/(m·K) with 20 wt% additive. • SsPCM holder absorbs 27 % of battery heat during fast charging. [ABSTRACT FROM AUTHOR]

The topics covered in this paper are relevant to the further development of polyurethane materials and propose a new method for producing sustainable and innovative foams. In this study, the effect of filler silanization on the flammability and thermal stability of rigid polyurethane foam (RPUF) was investigated. The RPUF composites study was preceded by an analysis of sunflower husk ash (SHA). Thermal decomposition behaviour and particle size distribution were carried out for the SHA samples. More, the elemental composition and structure of the fillers were investigated. The use of silanization of the filler results in homogenization of its structure. Sunflower husk ash has higher characteristic melting points than most biomass ashes and good thermal stability. The foam flammability results were preceded by an analysis of density and cell morphology. The use of silanized filler in RPUFs results in a homogenized structure and a 14 % reduction in apparent density. A wide range of tests were carried out as part of the flammability tests, which included: limiting oxygen index (LOI), gross calorific value, cone calorimeter, and optical density test. Additionally, thermal analysis methods were used to investigate the thermal stability of the foams. Flammability tests carried out confirm the positive effect of filler salinization on flammability. Heat release during combustion is reduced by 10 % and the release of toxic gases is also reduced. On the other hand, the thermal stability results are similar for foam with unmodified filler and those with silanized ash. Based on the comprehensive flammability and smoke results, a trend towards improved flame-retardant properties of RPUFs was observed. [Display omitted] • Sunflower husk ash consists mainly of Zn, Cr, B, Mn and Cu elements. • The addition of silanized ash to polyurethane foam reduces the apparent density. • Silanization of sunflower husk ash does not affect the thermal stability of foams. • Addition of silanized ash reduces the intensity of heat release during combustion. • Silanization reduces the amount of toxic gas release during fire. [ABSTRACT FROM AUTHOR]

Vanillin produced from lignin is an environmentally friendly compound having various active structures that can be crosslinked with hexanediamine and epoxidized soybean oil (ESO) to form water resistant composite. Inclusion of ammonium dihydrogen phosphate (ADP) could render the composite flame retardant, but its mechanical properties could be influenced. Therefore, walnut shell powder (WSP), as a common biomass waste, can be incorporated to improve its hardness and compressive strength. A matrix named VHEA was prepared by the condensation of vanillin, hexanediamine, ESO, and ADP. WSP was used as the skeleton for blending with VHEA to create VHEAW composite. Mechanical properties, dimensional stability, UV-resistance, thermal conductivity and flame retardancy of the composites were evaluated. The inclusion of WSP at a ratio of 1:1 to VHEA improved the compressive strength, Brinell hardness and flexural strength of the composite. Meanwhile, its water contact angle reaches 131.48 °, indicates its superior hydrophobicity. It also has high UV resistance and good flame retardancy as the LOI value is as high as 35.1 %, and its peak heat release rate is as low as 123.19 kW/m2. Its outstanding thermal insulation and flame retardancy, combined with excellent UV-resistance, render it suitable for various building components, including roofing, exterior siding, windows, and doors. [Display omitted] • Vanillin-based thermosetting composite was reinforced with walnut shell powder. • The composite exhibited good hydrophobicity and UV resistance. • Reinforcement of walnut shell powder improved the strength of the composite. • The composite had excellent flame retardancy. • Vanillin-based composite exhibited outstanding thermal insulation properties. [ABSTRACT FROM AUTHOR]

This study investigates the unidirectional (UD) jute/snake plant fiber-reinforced epoxy composites with various fiber weight percentages (100/0, 75/25, 50/50, 25/75, and 0/100) manufactured by the hand lay-up technique. Their mechanical properties (tensile, flexural, and impact), thermal properties (thermal conductivity, heat resistance, thermal stability, and thermal transitions (e.g., melting, crystallization, and T g)), water absorption, and morphologies are then evaluated. It is found that the UD hybrid composite made with 25 % jute and 75 % snake plant exhibits better tensile modulus and strength of 4.02 GPa and 112.83 MPa, respectively, and maximum impact strength of 185.18 kJ/m2, whereas the UD hybrid composite of 50 % jute/50 % snake plant shows a maximum flexural strength of 159.89 MPa. The thermal conductivity of UD composites increases with the increase in snake plant fiber, and the UD hybrid composite consisting of 75 % jute/25 % snake plant displays the minimum thermal conductivity (0.20 W/mK). Thermogravimetric and differential scanning calorimetry analyses show that all UD composites offer moderate thermal stability at high temperatures. The degree of water absorption of UD composites decreases with increasing snake plant fiber, and the UD composite of 25 % jute/75 % snake plant shows minimum water absorption. The outcome of this study indicates that the UD hybrid composites with comparatively higher contents of snake plant fiber can potentially be used for applications where significant mechanical properties are required with moderate thermal stability (e.g., aircraft interior panels, car door panels, seat foundations, the inner structure of trains, helmets, surfboards, and so on). [Display omitted] • Composite comprising 25 % jute and 75 % snake plant exhibits better tensile properties and impact strength. • Flexural strength increases with increasing snake plant fiber except for slight inconsistency. • Failures of composites occur predominately due to fiber pull-out, fracture of fibers, fiber-matrix debonding, and voids. • Thermal conductivity of composites rises with the increase in snake plant fiber. • All composites represent moderate thermal stability at high temperatures. [ABSTRACT FROM AUTHOR]

With the increasing demand for highly integrated circuits to optimize energy efficiency, reduce weight, and improve mechanical properties, finding a Magnesium (Mg) matrix material with excellent mechanical strength and high thermal conductivity poses a significant challenge. In this work, titanium (Ti) particles were introduced into AZ91 (Mg-9Al-1Zn) alloy to fabricate Ti/AZ91 composites, employing a combination of stir casting, extrusion and rolling processes. This strategy simultaneously enhances the mechanical properties and thermal conductivity of the Ti/AZ91 composites compared with AZ91 alloy. The incorporation of Ti particles serves to refine grains, expediting the formation of Mg 17 Al 12 phase within the Mg matrix. Optimal comprehensive mechanical properties are attained in 10 wt% Ti/AZ91 composite, exhibiting an ultimate tensile strength of 365 MPa, an elongation of 11.9 %, and a significantly low wear rate of 4.548×10−3 mm3/m. Notably, the 10 wt% Ti/AZ91 composite shows a 41.1 % reduction in wear rate relative to the AZ91 alloy, attributed to the incorporation of hard Ti particles. Furthermore, the thermal conductivity of the 2.5 wt% Ti/AZ91 composite exhibits a significant enhancement over that of the AZ91 alloy. Detailed discussions are provided on the fundamental mechanisms responsible for strengthening, wear resistance, and thermally conductive in Ti/AZ91 composites. These results highlight the substantial potential of Ti/AZ91 composites for lightweight structural applications, such as highly integrated circuits requiring excellent mechanical properties and high thermal conductivity. [Display omitted] • The 10Ti/AZ91 composite demonstrates a remarkable improvement in UTS, EL and wear resistance. • Enhanced mechanical properties results from the deformable Ti particles, refined grains, and weakening of texture. • The Ti/AZ91 composites possess exceptional thermal conductivity while maintaining high strength. [ABSTRACT FROM AUTHOR]

Spark plasma sintering (SPS) shows great potential in the fabrication of bulk YH 2- x. For the first time, the high-pressure SPS (HPSPS) of YH 2- x is explored and compared with the routine SPS. It is found that HPSPS remarkably reduces the densification temperature, and thus the thermal dehydrogenation phase transition (δ-YH 2- x → α-Y) and the hydrogen loss of YH 2- x can be avoided. Nearly fully dense δ-YH 1.80 monolith is successfully prepared by HPSPS under 500 MPa at a relatively low temperature of 800 °C. HPSPS is effective in overcoming the thermal dehydrogenation problem during the sintering of YH 2- x. Compared with significant grain growth in the routine SPS, the grain growth in the HPSPS is very limited. In terms of thermal properties, the thermal conductivity of HPSPS prepared YH 2- x is relatively low below 600 °C, then tends to be closed above 600 °C, compared with routine SPS prepared and directly hydrided YH 2- x. The thermal expansion of HPSPS prepared dense YH 2- x is basically consistent with that of directly hydrided bulk. This study provides a valuable reference for the sintering of high-quality δ-YH 2- x and other metal hydrides monoliths. • High-pressure SPS (HPSPS) is used to fabricate dense δ-YH 2- x for the first time. • The differences between routine SPS and HPSPS of dense YH 2- x are clarified. • HPSPS provides a "low-temperature sintering" and very limited grain growth. • The thermal dehydrogenation problem in the sintering of YH 2- x is overcome by HPSPS. [ABSTRACT FROM AUTHOR]

SiC is a promising structural material for future advanced nuclear energy systems. However, the inherent brittleness and difficulty of densification of SiC limits its practical application. In this study, medium entropy alloy (CrCoNi) reinforced silicon carbide composites (CCN/SiC) were sintered at 1950–2200°C by spark plasma sintering (SPS). The influence of CCN addition on the CCN/SiC composites was investigated in terms of microstructure, mechanical and thermal properties. The results show that SiC sintered at 2200℃ has the highest density, and the addition of 7.5 wt% CCN can significantly improve the fracture toughness of SiC. Transgranular fracture, crack deflection, and premature crack termination due to interfacial passivation are considered as potential toughening mechanisms. Although the addition of CCN can degrade the thermal conductivity of SiC ceramics, it has little effect on the structural stability of the SiC matrix at high temperatures. • A dimpled fracture feature was found in the CCN/SiC composites. • The composite exhibits very good structural stability at 1200 °C. • The addition of CrCoNi doubled the fracture toughness of SiC ceramics. [ABSTRACT FROM AUTHOR]

Anionic polyamide 6 (aPA6), synthesized via the ring-opening polymerization of ε-caprolactam, has emerged as a promising matrix for high-performance thermoplastic composites, offering advantages over conventional thermoplastics and thermosets. However, optimizing the microstructure and mechanical properties of aPA6 requires a comprehensive understanding of how processing conditions influence polymerization kinetics and resulting material characteristics. This work systematically investigates the interplay between two critical processing parameters, i.e., the mold temperature and catalysts concentration, on the microstructural and thermomechanical properties of aPA6, via a combined experimental and statistical approach. Increasing the mold temperature from 145 °C to 175 °C and the catalysts concentration led to a reduction in crystallinity, due to the promotion of polymerization over crystallization. Higher temperatures and concentrations also slightly anticipated thermal degradation onset from 388 °C to 327 °C. The elastic modulus decreased from 3.4 GPa to 2.7 GPa as temperature increased, primarily governed by the diminishing crystallinity. Similarly, the ultimate tensile strength declined from 80 MPa to 68 MPa with rising temperature. Interestingly, the strain at break exhibited a complex dependence, peaking at 48 % for an intermediate temperature of 165 °C and lower catalysts concentration, suggesting an optimal balance of crystallinity, branching, and high molecular weight. Statistical empirical models captured these relationships, enabling prediction and tailoring of aPA6 properties by tuning processing conditions. These insights pave the way for optimized manufacturing of high-performance aPA6 composites via techniques like thermoplastic resin transfer molding and expand potential applications to thermally sensitive reinforcements like natural fibers. [Display omitted] • Crystallinity reduced by increasing mold temperature and catalysts. • Elastic modulus peaked at 3.4 GPa with low mold temperatures. • Ultimate tensile strength rised from 68 MPa to 80 MPa with decreasing mold temperature. • Strain at break peaked at 48 % for 165 °C mold temperature and low catalysts concentration. • Statistical models captured property-processing relationships, enabling property tailoring. [ABSTRACT FROM AUTHOR]

Polydimethylsiloxane (PDMS) exhibits exceptional thermal stability and processability, however, limited adhesion and carbonization performance hinders its applications as flexible thermal protection materials. Herein, a phenolic epoxy modified silicone rubber (KFAP@PDMS) was synthesized, and the microscopic morphology, macroscopic mechanical properties, adhesive properties, thermal properties and ablative properties were systematically investigated. Compared to pure PDMS, the modified material exhibits a maximum tensile strength increase of 170 %, maximum elongation at break increases of 141 %, maximum adhesion strength increases of 209 %, and linear ablation rate decrease 84.9 %, respectively. Thermal degradation analysis indicates that the introducing of KFAP increases crosslink density while the degradation products mainly consist of D 3 , D 4 , and toluene compounds. Ablation analysis reveals that the inclusion of KFAP promotes an in-situ carbon-silicon multiphase ceramization reaction, resulting in densification of the carbon layer and significant improvement of the ablation performance. [Display omitted] • A carbon silicon composite hybrid network of phenolic epoxy silicone rubber was constructed. • The adhesion, mechanical and ablation properties of silicone rubber have been simultaneously improved. • Thermal degradation mechanism of hybrid material was discussed in detail. [ABSTRACT FROM AUTHOR]

General approaches for preparing epoxy vitrimers required lots of catalysts to accelerate transesterification to form the cross-linked network and the residual catalyst not only resulted in toxicity but also poor compatibility with other components. Herein, a green and facile strategy for preparing gallic acid epoxy resin (GA-EP) was developed under catalyst-free condition using renewable gallic acid, xylitol and hexahydro 4-methylphthalic anhydride (MHHPA) as feedstocks. The results indicated that the bio-based epoxy vitrimer had higher glass transition temperature (122 °C), satisfactory mechanical, thermal and degradation properties compared to neat Bisphenol A-based epoxy vitrimer. Furthermore, recycled GA-EP was ground into powder and added to the fresh resin to investigate its reusability. Compared to the original, the recycled epoxy vitrimer system demonstrated comparable performance, except for minor reductions in glass transition temperature (T g) and modulus, likely stemming from the inherent inhomogeneity of the reprocessed material. This work provides a new approach to the production of high T g bio-based epoxy vitrimers without adding any catalyst. [Display omitted] • Vitrimers based on gallic acid are utilitarian materials and prime contenders for industrial applications. • The glass transition temperature of the vitrimers was controlled by the addition of polyol (xylitol). • Gallic acid-derived catalyst-free epoxy vitrimers exhibit high T g (122.3–182.8 °C) and recyclability. [ABSTRACT FROM AUTHOR]

Mixing forest industrial by-products, wood chips, with cement to produce thermal insulation concrete can help reduce energy consumption associated with temperature control in buildings. However, wood chips-based concrete usually has low strength due to the incompatibility between wood chips and the widely used ordinary Portland cement (OPC). To address this issue, this study explored using belitic calcium sulfoaluminate (BCSA) cement to replace OPC to enhance the mechanical performance of wood chips-based thermal insulation concrete. The investigation includes the analysis of thermal properties, physical properties, unconfined compressive strength (UCS), hydration reaction, and carbon footprint analysis for mixtures. The findings show that the wood chips concrete achieved an average oven-dry bulk density of 803 kg/m3 and thermal conductivity of 0.237 W/mK, establishing it as a lightweight thermal insulation concrete. In addition, the UCS results highlight BCSA cement's superior compatibility with wood chips. When replacing OPC with BCSA cement, the one-day unconfined compressive strength (UCS) of wood chips concrete increased from 0.7 ± 0.0 MPa to 5.1 ± 0.0 MPa, and the 28-day UCS increased from 4.3 ± 0.2 MPa to 8.0 ± 0.4 MPa. The carbon footprint analysis showed that utilizing BCSA cement and wood chips to develop thermal insulation concrete can result in a negative net carbon footprint of −34 kg CO 2 per tonne of mixture. The results show that replacing OPC with BCSA cement in wood chips concrete can achieve higher mechanical performance, excellent thermal insulation properties, and a negative carbon footprint. • Thermal insulation concrete was developed with belitic calcium sulfoaluminate (BCSA) cement and wood chips. • BCSA cement significantly increased the strength of wood chips-based concrete. • BCSA cement showed better compatibility with wood chips than Portland cement. • Concrete developed with BCSA cement and wood chips has a negative carbon footprint. [ABSTRACT FROM AUTHOR]

The inferior mechanical strength and thermal resistance of foam concrete limited its application in thermal insulation engineering. This study focused on enhancing the mechanical strength and thermal resistance of foam concrete by incorporating glass lightweight microspheres (GLM) to partially replace foam. The roles of GLM in foam concrete were investigated through physical, mechanical, and thermal properties tests. The improvement mechanism behind the mechanical strength and thermal resistance was further revealed. Results indicated that the addition of GLM enhanced mechanical strength of foam concrete by promoting hydration reaction, optimizing pore structure, and improving GLM-paste interfaces. The mechanical strength of foam concrete with 20 % GLM increased by about 40 %. Moreover, GLM improved the residual compressive strength after exposure to 800°C, with an enhancement of 39.8 %. The inclusion of GLM reduced the risks of crack formation, densified the paste, and strengthened the foam wall due to its hollow structure, pozzolanic reactivity, melting and filling effects, and the phase transformation of additional C-S-H into well-packed wollastonite. Additionally, GLM with closed and isolated pores reduced the drying shrinkage and water absorption rate of foam concrete. The finding suggests that incorporating an appropriate amount of GLM can produce high-strength, low-density, and thermal-resistant foam concrete. • Using GLM to partially replace foam improved the performance of foam concrete. • Foam concrete with GLM had high strength of 23.6 MPa and density of 1100 kg/m3. • The introduction of GLM contributed to superior high-temperature resistance. • GLM improved pore structure, foam distribution, and pore wall of foam concrete. [ABSTRACT FROM AUTHOR]

• Cu(dmamp') 2 (1) using aminoalkoxide (dmamp' = 2-(dimethylamino)−2-methyl-1-propoxide) was synthesized. • A plausible dicomposition mechanism of 1 was presented through EI-MS, which suggests that 1 can be used as a single-source precursor for Cu metal thin films. • Thermal properties for 1 was characterized by TGA. • As the reaction temperature increasesse, CuO, Cu 2 O, and Cu were produced when producing nanoparticles utilizing 1. • While the volatility of 1 and the previously reported Cu(dmamp) 2 were similar, thermal stability of 1 was slightly better. Cu(dmamp') 2 (1) (dmamp' = 2-(dimethylamino)-2-methyl-1-propoxide) was synthesized for comparison according to the position of the substituent of aminoalkoxide. When comparing the properties such as structure, thermal stability, and usability with 1 and the previously reported Cu(dmamp) 2 (dmamp = 1-dimethylamino-2-methyl-2-propoxide), other properties were similar, but 1 had better thermal stability. Consequently, 1 is thought to be a better precursor for thin films and nanomaterials containing Cu. [Display omitted] [ABSTRACT FROM AUTHOR]

• Shear fracture properties of SCC granite specimens with varying heat treatments are investigated. • The acoustic emission (AE) characteristics are examined. • Fracture surface morphology is investigated by 3D laser scanning. • Attenuation of shear properties of heating-treated granites origin from microstructure degradation. The exploitation of geothermal resources enhances the energy structure but poses challenges related to thermal–mechanical issues. This study utilizes short core in compression (SCC) specimens of granite to investigate thermo-mechanical properties. We examined the effects of heat treatment temperature on physical properties, shear fracture toughness, as well as acoustic emission (AE) characteristics. Fracture surface morphology and microstructure of the heat-treated SCC specimens were also analyzed using 3D laser scanning and scanning electron microscopy. Results indicate that both mass loss and P-wave velocity decrease with increasing heating-treated temperature, and similar trends are observed in mechanical properties. Specifically, fracture energy and shear fracture toughness decline by 51.48 % and 61.27 %, respectively, as temperature rises from 25 °C to 750 °C. The b -value and proportion of shear cracks initially increase before falling, with an inflection point at 300 °C, linked to thermal-induced microstructural deterioration. Fractal dimension (D) and joint roughness coefficient (JRC) show significant increases with higher heat treatment temperatures. Microstructural degradation, including dehydration and thermal-induced microcracking, drives the reduction in shear properties of heat-treated granites. Overall, our findings offer valuable insights into determining various methods of heat storage reconstruction with great application potential. [ABSTRACT FROM AUTHOR]

The purpose of the present study to prepare hydroxypropyl derivatives (HP) instant (partially cold-water swell-able) starches via extrusion technique (Ex) from sorghum and corn. The native and hydroxypropylated (at propylene level 5 % and 12 %) starch extrudates were evaluated for functional, structural, thermal and rheological properties. The development of extrudates provides ease to industries as they are easily soluble in aqueous mediums and does not require any prior heating. The degree of substitution (DS) for all extrudates varied between 0.0083 and 0.1530 which is under limit and save to consume. The X-ray diffraction (XRD) analysis revealed that all extrudates exhibited V-type pattern while the intensity of peaks increased due to hydroxypropylation. The starch extrudates showed gel-like behavior since storage modulus (G′) was greater than loss modulus (G″). Non-Newtonian shear thinning behavior was observed for all extrudates. At lower temperature, HP-Ex at higher substitution level (12 %) demonstrated higher complex viscosity than native and low-substituted extrudates. Creep recovery of HP-Ex dispersion was more pronounced than native extrudates suggesting elastic nature of sorghum and corn starch extrudates. The differential scanning calorimetry (DSC) results revealed that HP-Ex were observed to gelatinize at lower temperatures and needed lower enthalpy of gelatinization (ΔH gel) because of their weakened structure after modification. • HP-Ex (hydroxypropylated extrudates) showed lower peak viscosity than native extrudates. • Percent crystallinity (%X) of HP-Ex decreased by 50 % compared to native counterparts. • HP-Ex exhibited elastic nature and showed better recoveries as compared to native extrudates. • HP-Ex showed better storage stability and are more suitable for refrigerated and frozen products. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fusion of covalent adaptable networks (CANs) with different mechanical properties using the diverse dynamic chemical bond. • CANs containing bi-dynamic bonds illustrate synergism and variable activation energy. • CANs exhibit outstanding puncture resistance properties and mechanical properties. Covalent adaptable networks (CANs) are widely used because of their outstanding mechanical properties and reprocessibility. However, these materials can only be recycled with mono-dynamic bonding networks during recovery. Here, we report that fused polymer CANs containing bi-dynamic bonds with adjustable mechanical properties are achieved through the dynamic behavior of the β -amino ester bond and the enamine-one bond. The β -amino ester bond-based CANs (P1) and the enamine-one bond-based CANs (P5) were prepared using tris(2-aminoethyl)amine (TREN) and m-xylylenediamine (MXDA) with hexanediol diacrylate and hexane-1, 6-diyl dipropiolate via click reaction, respectively. The mechanical and thermal properties of the fused films obtained after grinding and mixing at room temperature were comparable to those of CANs containing bi-dynamic bonds obtained by pre-mixing TREN and MXDA. Dynamic exchange and topological bond formation by the β -amino ester and the enamine-one at the interface are shown at the molecular level and with high uniformity. CANs containing bi-dynamic bonds showed synergism in stress relaxation experiments, demonstrating variable activation energies over a range of the temperature window. Owing to their excellent puncture resistance, the prepared materials can be used in flexible devices, energy-storage equipment, and various other applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel phenolic resins with phosphazene derivative (CHPP) were synthesized. • The prepared phenolic resins reveal high thermal stability and char yield. • The line ablation rate of prepared phenolic resins was as low as 0.0020 mm/s. • The CHPP could promote the formation of char yield during ablation and carbonization. A novel phenolic resin with combined hydroxymethyl-substituted phosphazene unit as a part of cured network was prepared which exhibited excellent thermal properties and ablation resistance. The novel phenolic resin was synthesized via copolymerizing from hexa (4-hydroxymethylphenoxy) cyclotriphosphazene (CHPP), phenol and paraformaldehyde. The CHPP contains abundant –CH 2 OH groups, which can be a part of phenolic resin network through condensation reactions between the –CH 2 OH groups and active hydrogens on benzene rings of phenolic resins. The optimal curing temperature for the modified phenolic resins was determined using the non-isothermal DSC method. The ablation resistance was investigated using the oxyacetylene flame method. The char yield and linear ablation rate of the modified phenolic resins are 71.3 % and 0.0020 mm/s, respectively. The ablation resistance of the novel resin is significantly improved, compared with other phenolic resin composites. The modification method for the phenolic resin provides a novel pathway to improve the application prospects of phenolic resins in the field of thermal protective materials. [ABSTRACT FROM AUTHOR]