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The annual changes of the scallop’s adductor muscle in Ca2+-ATPase activity, chymotryptic digestion, endogenous fluorescence spectra, sulfhydryl content, and surface hydrophobicity were studied. Ca2+-ATPase activity peaked in February and reached its minimum in August for males and in July for females. However, no significant differences were observed between males and females throughout the year. The inactivation rate of Ca2+-ATPase activity increased by 17- to 36-fold when the temperature rose from 38°C to 45°C. The ratio of free myosin to bound myosin was approximately 5:4 at 0.5  M KCl and changed to 5:1 at 1.0  M, as determined by modeling. Chymotryptic digestion demonstrated that scallop myosin could be cleaved into S-1/rod portions at 0.1  M and HMM/LMM at 0.5  M KCl. Furthermore, no significant seasonal variations were observed in chymotryptic digestion patterns, endogenous fluorescence, surface hydrophobicity, or sulfhydryl content. In conclusion, the structure and thermal stability of both male and female scallops remained stable throughout the year, making them suitable for processing and preservation. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) composite serve as widely used filaments in fused deposition modeling (FDM) 3D printing. This study investigates the enhancement of PLA composite's comprehensive mechanical properties and thermal stability through the incorporation of carbon fiber (CF). The influence of FDM process parameters on the mechanical properties of PLA composite is also analyzed. Results show that adding 5 wt.% CF significantly enhances the stiffness and comprehensive mechanical properties of PLA composite. The order of printing factors affecting the tensile strength of the PLA composite product is as follows: printing layer thickness, bottom plate temperature, printing speed, and nozzle temperature. Finally, optimal tensile strength is achieved under specific conditions: 0.1 mm layer thickness, 60 °C bottom plate temperature, 40 mm/s printing speed, and 215 °C nozzle temperature. [ABSTRACT FROM AUTHOR]

Thermoplastic polyurethanes (TPUs) are a family of thermoplastic elastomers with great properties such as high elongation and excellent chemical and abrasion resistance, which are processable by conventional melting methods. Nevertheless, TPUs lose mechanical properties and thermal stability at higher temperatures. In this work, we designed and synthesized a new TPU with limited crosslinking of the soft segments in order to improve its performance at high temperatures while preserving processability. Additionally, the new TPU maintains its transparency. With the incorporation of 10% trifunctional polyol, the Tg was increased by 7°C, the storage modulus at room temperature (25°C) was improved by 412 MPa (136%), the rubbery plateau was extended by 32°C and the thermal stability was enhanced by 4°C at T5. Moreover, the TPU with controlled crosslinking of the soft segments shows exceptional creep behavior both at room temperature and at 150°C, where the creep rate decreased by 80%. The new TPU shows limited decrease in tensile properties and can be processed by conventional thermoplastic processing techniques. Highlights: Design and synthesis of a new TPU with limited crosslinking of the soft segments.Incorporation of the crosslinks into the soft segments preserves system processability.Enhanced mechanical and thermal properties while preserving system transparency.High temperature application window extended by 32°C.Creep rate at 150°C lowered by 80%. [ABSTRACT FROM AUTHOR]

Bamboo fiber has garnered considerable attention owing to its high specific strength and renewability. However, the hydrophilic nature of the material must be carefully managed to create a bamboo composite with usable thermal‐mechanical properties. Herein, the NaOH‐treated bamboo fiber (particle size ≤200 μm) was used to produce bamboo charcoal (BC). Then, recycled low‐density polyethylene containing BC composites was fabricated by varying the BC composition (between 2 and 8 wt%). Effects of different BC wt% in the BC/recycled low‐density polyethylene composites (denoted as xBCPE, where x indicates BC wt% in the composites) were analyzed for tensile strength, morphology, and thermal properties. In addition, the water absorption capacities of the BCPE composites were compared. These xBCPE composites showed excellent thermal stability and low water absorption properties. Therefore, they are potential candidate materials for electrical device packaging with partial degradability. Highlights: Bamboo charcoal (BC) was prepared via low‐temperature pyrolysis of alkaline‐treated bamboo fiber.BC displayed strong interfacial interaction with recycled low‐density polyethylene.Proportion of BC on the composite properties was investigated and furnished.The xBCPE composites demonstrate low water absorption and excellent thermal stability.The reinforced composite (4BCPE) shows great promise as a functional material. [ABSTRACT FROM AUTHOR]

To meet the current demand for lead-free piezoelectric ceramics, a novel sol-gel synthesis route is presented for the preparation of Ba0.85Ca0.15Ti0.9Zr0.1O3 doped with cerium (Ce = 0, 0.01, and 0.02 mol%) and vanadium (V = 0, 0.3, and 0.4 mol%). X-ray diffraction patterns reveal the formation of a perovskite phase (space group P4mm) for all samples after calcination at 800 °C and sintering at 1250, 1350, and 1450 °C, where it is proposed that both dopants occupy the B site. Sintering studies show that V doping allows the sintering temperature to be reduced to at least 1250 °C. Undoped BCZT samples sintered at the same temperature show reduced functional properties compared to V-doped samples, i.e., d33 values increase by an order of magnitude with doping. The dissipation factor tan δ decreases with increasing sintering temperature for all doping concentrations, while the Curie temperature TC increases for all V-doped samples, reaching 120 °C for high-concentration co-doped samples. All results indicate that vanadium doping can facilitate the processing of BCZT at lower sintering temperatures without compromising performance while promoting thermal property stability. [ABSTRACT FROM AUTHOR]

Scholars are looking for solutions to substitute hazardous substances in manufacturing nanocellulose from bio-sources to preserve the world's growing environmental consciousness. During the past decade, there has been a notable increase in the use of cellulose nanocrystals (CNCs) in modern science and nanotechnology advancements because of their abundance, biocompatibility, biodegradability, renewability, and superior mechanical properties. Spherical cellulose nanocrystals (J–CNCs) were successfully synthesized from Jenfokie micro-cellulose (J–MC) via sulfuric acid hydrolysis in this study. The yield (up to 58.6%) and specific surface area (up to 99.64 m2/g) of J–CNCs were measured. A field emission gun–scanning electron microscope (FEG-SEM) was used to assess the morphology of the J–MC and J–CNC samples. The spherical shape nanoparticles with a mean nano-size of 34 nm for J–CNCs were characterized using a transmission electron microscope (TEM). X-ray diffraction (XRD) was used to determine the crystallinity index and crystallinity size of J–CNCs, up to 98.4% and 6.13 nm, respectively. The chemical composition was determined using a Fourier transform infrared (FT–IR) spectroscope. Thermal characterization of thermogravimetry analysis (TGA), derivative thermogravimetry (DTG), and differential thermal analysis (DTA) was conducted to identify the thermal stability and cellulose pyrolysis behavior of both J–MC and J–CNC samples. The thermal analysis of J–CNC indicated lower thermal stability than J–MC. It was noted that J–CNC showed higher levels of crystallinity and larger crystallite sizes than J–MC, indicating a successful digestion and an improvement of the main crystalline structure of cellulose. The X-ray diffraction spectra and TEM images were utilized to establish that the nanocrystals' size was suitable. The novelty of this work is the synthesis of spherical nanocellulose with better properties, chosen with a rich source of cellulose from an affordable new plant (studied for the first time) by stepwise water-retted extraction, continuing from our previous study. [ABSTRACT FROM AUTHOR]

Rigid porous polymeric monoliths are robust, highly efficient, versatile stationary phases. They offer simple preparation and convenient modification provided by a whole range of synthesis factors, e.g., starting monomers, cross-linkers, initiators, porogens, polymerization techniques, and temperature. The main aim of this study was to synthesize polymeric monoliths and determine the correlation between polymerization parameters and the porosity and thermal stability of the obtained materials. Polymeric monoliths were synthesized directly in HPLC columns using N-vinyl-2-pyrrolidone (NVP) and 4-vinylpiridine (4VP) as functional monomers, with trimethylolpropane trimethacrylate (TRIM) serving as the cross-linking monomer. During copolymerization a mixture of cyclohexanol/decane-1-ol was used as the pore-forming diluent. Polymerization was carried out at two different temperatures: 55 and 75 °C. As a result, monoliths with highly developed internal structure were synthesized. The value of their specific surface area was in the range of 92 m2/g to 598 m2/g, depending on the monomer composition and polymerization temperature. Thermal properties of the obtained materials were investigated by means of thermogravimetry (TG). Significant differences in thermal behavior were noticed between monoliths synthesized at 55 and 75 °C. Additionally, the poly(NVP-co-TRIM) monolith was successfully applied in GC analyses. [ABSTRACT FROM AUTHOR]

Functional cyclophosphazenes have proven to be effective modifiers of polymer materials, significantly improving their performance properties, such as adhesive characteristics, mechanical strength, thermal stability, fire resistance, etc. In this study, 4-(β-carboxyethenyl)phenoxy-phenoxycyclotriphosphazenes (CPPP) were obtained by the condensation of 4-formylphenoxy-phenoxycyclotriphosphazene with malonic acid. Its structure was studied using 31P, 1H, and 13C NMR spectroscopy and MALDI-TOF mass spectrometry, and the thermal properties were determined by DSC and TGA methods. Molecular modeling using the MM2 method showed that CPPPs are nanosized with diameters of spheres described around the molecules in the range of 1.34–1.93 nm, which allows them to be classified as nanosized structures. The epoxy resin DER-331 was cured with CPPP, and the conversion of epoxy groups was assessed using IR spectroscopy. Using optical interferometry, it was shown that CPPPs are well compatible with epoxy resin in the temperature range from 80 to 130 °C. It was established that the cured epoxy composition was fire resistant, as it successfully passed the UL-94 vertical combustion test due to the formation of porous coke during the combustion process and also had high heat resistance and thermal stability (decomposition onset temperature about 300 °C, glass transition temperature 230 °C). The composition has low water absorption, high resistance to fresh and salt water, fire resistance, and adhesive strength to steel and aluminum (11 ± 0.2 MPa), which makes it promising for use as an adhesive composition for gluing parts in the shipbuilding and automotive industries, the aviation industry, and radio electronics. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive investigation into the thermal stability of superlattice-like (SLL) thin films fabricated by varying the sputtering sequences of the SLL [Ge8Sb92(25nm)/GeTe(25nm)]1 and SLL [GeTe(25nm)/Ge8Sb92(25nm)]1 configurations. Our results reveal significantly enhanced ten-year data retention (Tten) for both thin films measured at 124.3 °C and 151.9 °C, respectively. These values surpass the Tten of Ge2Sb2Te5 (85 °C), clearly demonstrating the superior thermal stability of the studied SLL configurations. Interestingly, we also observe a distinct difference in the thermal stability between the two SLL configurations. The superior thermal stability of SLL [GeTe(25nm)/Ge8Sb92(25nm)]1 is attributed to the diffusion of the Sb precipitated phase from Ge8Sb92 to GeTe. This diffusion process effectively reduces the impact of the Sb phase on the thermal stability of the thin film. In contrast, in the case of SLL [Ge8Sb92(25nm)/GeTe(25nm)]1, the presence of the Sb precipitated phase in Ge8Sb92 facilitates the crystallization of GeTe, leading to reduced thermal stability. These findings underscore the significant influence of the sputtering sequence on the atomic behavior and thermal properties of superlattice-like phase change materials. Such insights provide a robust foundation for the design and exploration of novel phase change materials with improved thermal performance. [ABSTRACT FROM AUTHOR]

Dy 2 O 3 –Sm 2 O 3 co-doped transparent glass ceramics (GCs) containing NaBi(WO 4) 2 crystalline phase were prepared by melt-curing-crystallization method. The optimal heat treatment condition is 580 °C/2 h. The optimum incorporation concentration of Dy 2 O 3 is 0.4%, exceeding which a quenching phenomenon dominated by quadrupole-quadrupole interactions emerges. Meanwhile, when the concentration of Dy 2 O 3 was fixed, the chromaticity coordinate of the sample moved the cool white light region to the warm white light region as the concentration of Sm 2 O 3 increased. The temperature-dependent emission spectra of the 0.4% Dy 2 O 3 -0.7% Sm 2 O 3 co-doped GC samples show that emission intensity at 575 nm at 185 °C still reaches 80% of the room temperature. The thermal quenching activation energy was 0.1537 eV and the activation energy after the addition of Mo6+ was 0.1957 eV. This study indicates that Dy 2 O 3 –Sm 2 O 3 co-doped GCs containing NaBi(WO 4) 2 crystalline phase can achieve light-color tunable emission, which is potentially valuable for solid-state color rendering and illumination applications. [ABSTRACT FROM AUTHOR]

Only 0.1% of polyurethanes available on the market are from renewable sources. With increasing concern about climate change, the substitution of monomers derived from petrochemical sources and the application of eco-friendly synthesis processes is crucial for the development of biomaterials. Therefore, polyhydroxyurethanes have been utilized, as their synthesis route allows for the carbonation of vegetable oils with carbon dioxide and the substitution of isocyanates known for their high toxicity, carcinogenicity, and petrochemical origin. In this study, polyhydroxyurethanes were obtained from carbonated soybean oil in combination with two diamines, one that is aliphatic (1,4-butadiamine (putrescine)) and another that is cycloaliphatic (1,3-cyclohexanobis(methylamine)). Four polyhydroxyurethanes were obtained, showing stability in hydrolytic and oxidative media, thermal stability above 200 °C, tensile strength between 0.9 and 1.1 MPa, an elongation at break between 81 and 222%, a water absorption rate up 102%, and contact angles between 63.70 and 101.39. New formulations of bio-based NIPHUs can be developed with the inclusion of a cycloaliphatic diamine (CHM) for the improvement of mechanical properties, which represents a more sustainable process for obtaining NIPHUs with the physicochemical, mechanical, and thermal properties required for the preparation of wound dressings. [ABSTRACT FROM AUTHOR]

Physical parameters are necessary to determine the suitability of the chalcogenide materials for specific applications. The present study reports the physical characteristics of the multicomponent GeTe2-x(SeSb)x (x = 0, 0.2, 0.4, 0.6) chalcogenide glasses synthesised by the melt-quench technique. The differential scanning calorimetric (DSC) technique has been used at separate heating rates β = 5, 10, 15, 20 °C / min. XRD and SEM–EDX studies have been carried out for structural and morphological analyses. The average coordination number and constraints of the compound have been calculated which indicates that the composition forms a glassy system. Lone pair electrons present in the composition have been evaluated. R parameter has a value greater than 1, indicating that the composition has sufficient chalcogen, chalcogen–chalcogen and heteropolar bonds. The overall bond energy of the compound has been calculated using the chemical bonding approach to understand the fine-structure properties of the compound. Cohesive energy has been observed to increase with composition. Thermal stability, glass transition temperature and glass forming ability of the compound have been calculated using different relations like Saad and Poulin relation, Dieztal relation, Hurby parameter (Hr) and reduced glass transition temperature (Trg) and studied theoretically to examine the thermal stability of the composition that shows that the prepared samples are suitable for data storage. [ABSTRACT FROM AUTHOR]

In civil construction, one of the primary challenges associated with wood application is its high flammability and low durability during fires. Although chemical treatment with fire-retardant properties exists, they are expensive and of non-renewable origin. Tannin, a wood extractive, being a phenolic compound, holds promise for enhancing the thermal properties of wood. This study aimed to assess the efficacy of tannin as a fire retardant and compare it with a commercial product, as well as comparing different application techniques for these products. Wood samples from the Simarouba amara Aubl. species were utilized. Tannin and a commercial flame retardant were applied via immersion, vacuum impregnation, brushing, and a treatment of tannin incorporated into water-based wood varnish. Alongside the burning test performance, assessments of the wood's physical properties, such as colorimetry, thermal stability, and mass retention, were conducted. The application of tannin altered the wood's color and reduced the spread of fire; its presence significantly reduced the flame duration and maintained the wood's structural integrity. However, tannin retention was lower compared to commercial flame retardant, leading to reduced fire retardancy. Among the methods tested, immersion proved to be the most effective in enhancing the wood's resistance to flame contact. [ABSTRACT FROM AUTHOR]

The effect of T4 and T6 treatment on the microstructures, precipitates, thermal expansion and thermal conductivity properties of Mg-2Nd-4Zn alloys was systemically investigated. The number of NdZn2 phase increased subjected to T6 treatment. The coherent relationship between the NdZn2 phase and Mg matrix was observed in the Mg-2Nd-4Zn alloys, which plays a great influence on improving the thermal expansion, thermal conductivity and mechanical properties of Mg-2Nd-4Zn alloys. The decrease in the coefficient of thermal expansion (CTE) and the thermal conductivity of Mg alloys were ascribed to the existence of solute atoms in alloys after the T4 treatment. It was also found that the T6-treated alloy has smaller area of the hysteresis loop, which has better thermal stability. Therefore, the high performance was mainly due to T6 treatment, the thermal conductivity of T6-treated Mg-2Nd-4Zn alloy is 124.4 K·m−1·K−1 at room temperature, and TYS of 235.5 MPa, CYS of 393.7 MPa, elongation of tension and compression are 31 and 27%, respectively. [ABSTRACT FROM AUTHOR]

Woven flax-carbon hybrid polyamide biocomposites offer a blend of carbon fibers' mechanical strength and flax's environmental advantages, potentially developing material applications. This study investigated their thermal behavior, degradation kinetics, and durability to water uptake and relative humidity exposure and compared them with pure flax and carbon composites with the same matrix. The hybrid composite exhibited intermediate water/moisture absorption levels between pure flax and carbon composites, with 7.2% water absorption and 3.5% moisture absorption. It also displayed comparable thermal degradation resistance to the carbon composite, effectively maintaining its weight up to 300 °C. Further analysis revealed that the hybrid composite exhibited a decomposition energy of 268 kJ/mol, slightly lower than the carbon composite's value of 288.5 kJ/mol, indicating similar thermal stability. Isothermal lifetime estimation, employing the activation energy (Ed) and degree of conversion facilitated by the Model Free Kinetics method, indicated a 41% higher service life of the hybrid laminate at room temperature compared to the carbon laminate. These insights are crucial for understanding the industrial applications of these materials without compromising durability. [ABSTRACT FROM AUTHOR]

Drug candidates must undergo thermal evaluation as early as possible in the preclinical phase of drug development because undesirable changes in their structure and physicochemical properties may result in decreased pharmacological activity or enhanced toxicity. Hence, the detailed evaluation of nitrogen-rich heterocyclic esters as potential drug candidates, i.e., imidazolidinoannelated triazinylformic acid ethyl esters 1–3 (where R1 = 4–CH3 or 4–OCH3 or 4–Cl, and R2 = –COOC2H5) and imidazolidinoannelated triazinylacetic acid methyl esters 4–6 (where R1 = 4–CH3 or 4–OCH3 or 4–Cl, and R2 = –CH2COOCH3)—in terms of their melting points, melting enthalpy values, thermal stabilities, pyrolysis, and oxidative decomposition course—has been carried out, using the simultaneous thermal analysis methods (TG/DTG/DSC) coupled with spectroscopic techniques (FTIR and QMS). It was found that the melting process (documented as one sharp peak related to the solid–liquid phase transition) of the investigated esters proceeded without their thermal decomposition. It was confirmed that the melting points of the tested compounds increased in relation to R1 and R2 as follows: 2 (R1 = 4–OCH3; R2 = –COOC2H5) < 6 (R1 = 4–Cl; R2 = –CH2COOCH3) < 5 (R1 = 4–OCH3; R2 = –CH2COOCH3) < 3 (R1 = 4–Cl; R2 = –COOC2H5) < 1 (R1 = 4–CH3; R2 = –COOC2H5) < 4 (R1 = 4–CH3; R2 = –CH2COOCH3). All polynitrogenated heterocyclic esters proved to be thermally stable up to 250 °C in inert and oxidising conditions, although 1–3 were characterised by higher thermal stability compared to 4–6. The results confirmed that both the pyrolysis and the oxidative decomposition of heterocyclic ethyl formates/methyl acetates with para-substitutions at the phenyl moiety proceed according to the radical mechanism. In inert conditions, the pyrolysis process of the studied molecules occurred with the homolytic breaking of the C–C, C–N, and C–O bonds. This led to the emission of alcohol (ethanol in the case of 1–3 or methanol in the case of 4–6), NH3, HCN, HNCO, aldehydes, CO2, CH4, HCl, aromatics, and H2O. In turn, in the presence of air, cleavage of the C–C, C–N, and C–O bonds connected with some oxidation and combustion processes took place. This led to the emission of the corresponding alcohol depending on the analysed class of heterocyclic esters, NH3, HCN, HNCO, aldehydes, N2, NO/NO2, CO, CO2, HCl, aromatics, and H2O. Additionally, after some biological tests, it was proven that all nitrogen-rich heterocyclic esters—as potential drug candidates—are safe for erythrocytes, and some of them are able to protect red blood cells from oxidative stress-induced damage. [ABSTRACT FROM AUTHOR]

The ZrO 2 fiber paper exhibits excellent thermal insulation properties, however, its limited mechanical strength and insufficient thermal stability hinder its widespread applications. The composite fiber papers, using mullite fibers possessing a high aspect ratio and exceptional thermal stability combined with ZrO 2 fibers, were fabricated via a vacuum-assisted filtration method. This method involved the successive stacking of composite fibers with alumina sol, using vacuum-induced directed water flow to create a layered structure reminiscent of nacre. The layered structure of the nacre, which demonstrates remarkable strength and hardness, has also served as a source of inspiration for the architectural design of the fiber paper. The tensile strength of pure ZrO 2 fiber paper was significantly enhanced by the addition of 7 wt% mullite fibers, resulting in a remarkable increase to 0.1805 kN/m. The paper exhibited exceptional resistance to bending, maintaining 96 % of its bending strength even after undergoing 100 cycles. The thermal shrinkage of the composite paper, containing 15 wt% mullite fibers, was reduced from 17.75 % observed in pure ZrO 2 fiber paper to a mere 1.32 % after undergoing heat treatment at a temperature of 1300 °C for 2 h. The composite paper, measuring 5 mm in thickness and consisting of 7 wt% compositions, displayed exceptional thermal insulation properties when exposed to a hot side temperature of 1370 °C. It effectively insulated temperatures up to approximately 1000 °C. [ABSTRACT FROM AUTHOR]

Recently, CaO‐doped (≤4 mol.%) tetragonal zirconia (CaSZ) ceramic was recommended as a potential alternative to yttria‐stabilized ZrO2 (YSZ). Here, we investigate the limits of starting particle sizes on the stability of tetragonal (t) phase and other associated benefits on measured properties. Synthesized CaSZ powders calcined with different temperatures were used as a mono‐sized or mixed (i.e., two different calcination temperatures) batch fraction for making dense CaSZ ceramic. The mixed‐batch powders were found to be far more efficient in stabilizing the t‐phase in ceramic. Compared to YSZ, CaSZ recorded remarkable enhancement in toughness (up to 8.3 MPa m$\sqrt {\mathrm{m}} $). Contrary to YSZ, CaSZ ceramic demonstrated outstanding thermal stability. [ABSTRACT FROM AUTHOR]

The long-term operation of motors induces substantial alterations in the surface conductivity and nonlinear coefficient of anti-corona paint, diminishing its efficacy and jeopardizing the longevity of large motors. Hence, the development of high-performance anti-corona paint holds paramount importance in ensuring motor safety. In this study, we integrate two nano-fillers, namely silicon carbide (SiC) and organic montmorillonite (O-MMT), into a composite matrix comprising micron silicon carbide and epoxy resin (SiC/EP). Subsequently, three distinct types of anti-corona paint are formulated: SiC/EP, Nano-SiC/EP, and O-MMT/SiC/EP. Remarkably, O-MMT/SiC/EP exhibits a glass transition temperature about 25 °C higher than that of SiC/EP, underscoring its superior thermal properties. Moreover, the introduction of nano-fillers markedly augments the surface conductivity of the anti-corona paint. Aging tests, conducted across varying temperatures, unveil a notable reduction in the fluctuation range of surface conductivity post-aging. Initially, the nonlinear coefficients exhibit a declining trend, succeeded by an ascending trajectory. The O-MMT/SiC/EP composite displays a maximum nonlinearity coefficient of 1.465 and a minimum of 1.382. Furthermore, the incorporation of nanofillers amplifies the dielectric thermal stability of epoxy resin composites, with O-MMT/SiC/EP showcasing the pinnacle of thermal endurance. Overall, our findings elucidate the efficacy of nano-fillers in enhancing the performance and longevity of anti-corona paint, particularly highlighting the exceptional attributes of the O-MMT/SiC/EP composite in bolstering motor safety through improved thermal stability and electrical properties. [ABSTRACT FROM AUTHOR]

This study primarily aimed to enhance the extraction of cutin from industrial tomato peel residues. Initially, the conventional extraction process was optimized using response surface methodology (RSM). Subsequently, high-pressure homogenization (HPH) was introduced to improve extraction efficiency and sustainability. The optimization process focused on determining the optimal conditions for conventional extraction via chemical hydrolysis, including temperature (100–130 °C), time (15–120 min), and NaOH concentration (1–3%). The optimized conditions, determined as 130 °C, 120 min, and 3% NaOH solution, yielded a maximum cutin extraction of 32.5%. Furthermore, the results indicated that applying HPH pre-treatment to tomato peels before alkaline hydrolysis significantly increased the cutin extraction yield, reaching 46.1%. This represents an approximately 42% increase compared to the conventional process. Importantly, HPH pre-treatment enabled cutin extraction under milder conditions using a 2% NaOH solution, reducing NaOH usage by 33%, while still achieving a substantial cutin yield of 45.6%. FT-IR analysis confirmed that cutin obtained via both conventional and HPH-assisted extraction exhibited similar chemical structures, indicating that the main chemical groups and structure of cutin remained unaltered by HPH treatment. Furthermore, cutin extracts from both conventional and HPH-assisted extraction demonstrated thermal stability up to approximately 200 °C, with less than 5% weight loss according to TGA analysis. These findings underscore the potential of HPH technology to significantly enhance cutin extraction yield from tomato peel residues while utilizing milder chemical hydrolysis conditions, thereby promoting a more sustainable and efficient cutin extraction process. [ABSTRACT FROM AUTHOR]

This study explores the impact of non-stoichiometric aluminum oxide (AlxOy) coatings applied via thermal atomic layer deposition (ALD) on carbon fiber fabrics (CFFs), emphasizing volume per cycle, FESEM analyses, color transitions, and thermal stability enhancements. Using trimethylaluminum and water at 100 °C, AlxOy was deposited across a range of 1000 to 5000 ALD cycles, with film thicknesses extending up to 500 nm. This notable increase in the volume of material deposited per cycle was observed for the 3D CFFs, highlighting ALD's capability to coat complex structures effectively. FESEM analyses revealed the morphological evolution of CFF surfaces post-coating, showing a transition from individual grains to a dense, continuous layer as ALD cycles increased. This morphological transformation led to significant color shifts from green to red to blue, attributed to structural coloration effects arising from variations in film thickness and surface morphology. Thermogravimetric analyses (TGA and dTG) indicated that the AlxOy coatings enhanced the thermal stability of CFFs, with a postponement in degradation onset observed in samples subjected to more ALD cycles. In essence, this research highlights the nuanced relationship between ALD processing parameters and their collective influence on both the aesthetic and functional properties of CFFs. This study illustrates ALD's potential in customizing CFFs for applications requiring specific color and thermal resilience, balancing the discussion between the surface morphological changes and their implications for color and thermal behavior. [ABSTRACT FROM AUTHOR]

Poly(butylene adipate‐co‐terephthalate) (PBAT) is one of the solutions to the energy crisis and white pollution. However, the poor thermo‐oxidative stability limits its wide applications. In this work, Chrysanthemum morifolium extract (CME) as a natural additive was used to modify the PBAT. The oxidation onset temperature (OOT) results showed that the CME could provide PBAT with high thermal oxidation stability. By the presence of 2.5 wt% CME, the OOT value of PBAT‐CME2.5 increased by 52°C compared with the neat PBAT. The outstanding antioxidant capacity is attributed to the excellent free radical quenching capacity of CME, whose main components consist of six kinds of phenolic compounds. Moreover, the PBAT‐CME1.5 composite could achieve the balance between the mechanical property and thermo‐oxidative stability, the OOT result of PBAT‐CME1.5 increased by 42°C, the tensile strength reached 103.1%, and the elongation at break could retain 91.4% of that of neat PBAT. Besides, the processing property, degradation performance, and surface hydrophobic nature of modified PBAT samples were all improved. This work proposes a facile method to obtain completely natural biodegradable composites to expand the practical applications of PBAT. Highlights: The main components in CME are phenolic compounds.CME showed high free radical scavenging efficiency.CME improved the thermal oxidation stability of the PBAT matrix.The addition of CME could still maintain good mechanical properties of PBAT.The introduction of CME promoted the degradation of PBAT films. [ABSTRACT FROM AUTHOR]

2,6-Di-tert-butyl-4-methylphenol (BHT) is an excellent antioxidant that is easily oxidized to 2,6-di-tert-butyl-4-hydroperoxyl-4-methyl-2,5-cyclohexadienone (BHTOOH). For the safety of BHT production and usage, it is meaningful to study the thermal stability and decomposition properties of BHT and BHTOOH. In this paper, the thermal decomposition properties of BHT and BHTOOH were compared by the mini closed pressure vessel test (MCPVT) and differential scanning calorimetry (DSC). Their kinetics of thermal decomposition were studied using thermogravimetric analysis (TGA). The thermal decomposition products of BHT and BHTOOH were analyzed by gas chromatography-mass spectrometry (GC–MS). The results show that there was no significant change in temperature pressure when BHT was warmed up under a nitrogen atmosphere, indicating that BHT was stable within 400 K. The thermal decomposition reaction of BHTOOH was rapid with an initial reaction temperature of 375.2 K. The initial exothermic temperature (Ti) and heat release (QDSC) of DSC were 384.9 K and 865.0 J g−1, respectively. The apparent activation energies (Ea) for the thermal decomposition reactions of BHT and BHTOOH calculated by the Kissinger method were 151.8 kJ mol−1 and 66.07 kJ mol−1, respectively. The main decomposition products of BHT were isobutene and 2-tert-butyl-4-methylphenol. The thermal decomposition products of BHTOOH included BHT, 2,6-di-tert-butyl-4-ethylphenol, 3,5-di-tert-butyl-4-hydroxybenzaldehyde, 4,4′-(1,2-ethanediyl) bis [2,6-bis (1,1-dimethylethyl) phenol, etc. Based on the thermal decomposition behavior and products, the reaction pathway has been described. These results indicate that BHT is a potential thermal hazard during production, storage and application. For the safety of the chemical industry, the oxidation of BHT should be avoided. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) is a bioresorbable and biodegradable polymer extensively used in various biomedical and engineering applications. In this study, we investigated the mass loss and thermal properties of PLA-multi-walled carbon nanotube (MWCNT) composites under simulated physiological conditions. The composites were prepared by melting PLA with 0.1, 0.5, 1.0, and 5.0 wt% MWCNTs using an ultrasonic agitator, and FTIR analysis confirmed composite formation. Subsequently, the composites were subjected to hydrolysis under simulated physiological conditions (pH 7.4 and 37 °C) for up to 60 days. The results revealed that the mass loss of the composites decreased with increasing MWCNT content, suggesting that the presence of MWCNTs decelerated the hydrolysis process. On day 58, the mass loss of pure PLA was 12.5%, decreasing to 8.34% with 0.1% MWCNT, 5.94% with 0.5% MWCNT, 4.59% with 1% MWCNT, and 3.54% with 5.0% MWCNT. This study offers valuable insights into the behavior of PLA-MWCNT composites under physiologically simulated conditions, facilitating the development of new polymer composites with enhanced thermal stability and degradation resistance for biomedical applications. [ABSTRACT FROM AUTHOR]

The potential cooling solutions for the next generation are represented by nanofluids, offering several advantages for various technological applications. The intriguing realm of glycine-based acetone-based Al 2 O 3 nanofluids was explored in the present investigation, with meticulous attention to details given to scrutinizing their stability and thermophysical properties. The stability of the nanofluids was determined through a trifecta of analytical methods, namely visual inspection, UV absorbance measurement, and zeta potential analysis, all applied with caution. The results revealed that stability was observed for a duration of 3 days without glycine, and an impressive 6 week period was achieved when supplemented with the surfactant. The incorporation of glycine enhanced the stability of the colloidal suspension without compromising its thermophysical attributes. Furthermore, the study involved an in-depth examination of the density, viscosity, specific heat, and thermal conductivity of the prepared nanofluids, yielding interesting outcomes. The data showed a marked increase in nanofluid density, viscosity, and thermal conductivity with a corresponding rise in volume concentration, while specific heat exhibited a noticeable reduction. These significant observations were meticulously compared to various existing theoretical models and proposed correlations in the literature. The heat transfer performance of the nanofluid in the context of pulsating heat pipes was evaluated and the results proved riveting. The nanofluid demonstrated superior performance compared to the base fluid, confirming its remarkable efficacy. [ABSTRACT FROM AUTHOR]

Improvement in thermal stability is especially important for the oxide/oxide composites, which are widely applied at high temperatures. Herein, the continuous alumina fiber reinforced alumina matrix (Al 2 O 3 /Al 2 O 3) composites were fabricated at 1200–1400 °C using Al 2 O 3 powders with a mean size of 0.6 μm. The Al 2 O 3 /Al 2 O 3 composite fabricated at 1300 °C achieved a high flexural strength of 392.9 ± 20.1 MPa and a high interlaminar shear strength of 20.6 ± 1.0 MPa. After exposure at 1000 °C for 100 h and 1400 °C for 10 min, the 1300 °C fabricated Al 2 O 3 /Al 2 O 3 composite showed no significant reduction in mechanical properties. A slight decrease in mechanical properties was observed after aging at 1200 °C for 100 h. The high strength retention after the heat treatment benefited from the coarse Al 2 O 3 powders, which could not be easily sintered at high temperatures. This work can expand the selection of the Al 2 O 3 /Al 2 O 3 composites for potential applications at service temperatures as high as 1400 °C for a short term. [ABSTRACT FROM AUTHOR]

Current highly integrated devices require heat interface materials with excellent heat conductivity. A simple approach was employed to synthesize thermally conductive and outstanding thermal stability nanocomposite. Calcium carbonate nanoparticles (nano CaCO 3) reinforced with reduced graphene oxide (rGO) nanoparticles (rGO/CaCO 3) are synthesized using a novel process, and the effect of rGO in CaCO 3 structure is examined by Field Emission Scanning Electron Microscope, X-ray diffraction, TGA-DTA, and thermal conductivity. The experimental results show that adding rGO resulted in higher crystallinity and thermal stability. As the wt.% of rGO increases from 1 to 5%, the crystallite size was suppressed by 21.06%, 27.39%, 32.48%, 41.5%, and 45.30%, respectively, compared to the pure nano-CaCO 3. Additionally, rGO enhances the thermal conductivity by 35.31% and thermal diffusivity to 1.834 mm2/s by adding 5% rGO. [ABSTRACT FROM AUTHOR]

Melt-quenching techniques were employed to produce a series of Nd 2 O 3 doped Al 2 O 3 –Na 2 O–WO 3 –B 2 O 3 glasses. Structure, optical, and thermal properties were investigated to illustrate the effectiveness of the Nd3+ ions in enhancement performance and analyze their behaviour. Nd 2 O 3 demonstrably contributed to the composite, as evidenced by evaluating all features. The density marginally rises with the addition of Nd 2 O 3 instead of B 2 O 3. The relevant physical characteristics had been calculated. The structure was analyzed by FTIR measurement and identified the vibration modes of varied concentrations. From FTIR spectra, N 4 values were reckoned, and the conversion of the network structure unit from BO 3 to BO 4 was verified. Numerous significant peaks have been caught in the absorption bands of the UV–Vis–NIR measurement. Optical bandgap and band tail are determined. DSC measurements were utilized to identify the thermal characteristics. As Nd3+ ions increased, glass thermal stability improved. Overall, the Nd3+ ion modifier rule was realized. [ABSTRACT FROM AUTHOR]

The glass composition (70-x)PbO-(30-y)B2O3-(x+y)AlF3, where x and y ranges from 0 to 20 mol%, were prepared using the conventional melt-quenching-annealing technique. The structural and thermal properties of the glasses were comprehensively analyzed using techniques like Differential Thermal Analysis (DTA), Dilatometry, Fourier-Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Scanning Electron Microscopy (SEM). XRD confirmed the amorphous, non-crystalline structure of the glasses. The glass network was found to be composed of structural units such as PbO4, BO4, BO3 and AlO6 using FTIR spectroscopy. FTIR analysis revealed significant structural changes, including the transformation of BO4 to BO3 units and the increase in non-bridging bonds, particularly with higher AlF3 content. DTA was instrumental in determining characteristic temperatures, such as the glass transition, melting, and peak crystallization temperatures, along with glass stability parameters (ΔT, Hr, Tgr) for all samples. The study found that the addition of AlF3 led to a decrease in these characteristic temperatures when replacing B2O3, but an increase when replacing PbO. Variations in the density and thermal expansion of the lead borate glass were observed upon the addition of AlF3, decreasing when substituting for PbO and increasing when substituting for B2O3. These findings provide insights into the properties of oxyfluoride glasses, paving the way for future optimization in their composition for varied applications. [ABSTRACT FROM AUTHOR]

Sustainable building materials with excellent thermal stability and sound insulation are crucial for eco-friendly construction. This study investigates biocomposites made from cellulose pulp reinforced with beeswax, fir resin, and natural fillers like horsetail, rice flour, and fir needles. Eight formulations were obtained, and their thermal resistance, oxidation temperature, and acoustic properties were evaluated. Biocomposites exhibited significant improvements compared to conventional materials. Oxidation temperature onset increased by 60–70 °C compared to polyurethane foam or recycled textiles, reaching 280–290 °C. Sound absorption coefficients ranged from 0.15 to 0.78, with some formulations exceeding 0.5 across mid-frequencies, indicating good sound-dampening potential. These findings demonstrate the promise of these biocomposites for sustainable construction, offering a balance of thermal and acoustic performance alongside environmental and health benefits. [ABSTRACT FROM AUTHOR]

In this work, the EVOH/Ti3C2 composite fibers were prepared via electrospinning and the effect of added Ti3C2 on the structure and properties of electrospun EVOH fibrous membranes was further investigated. The morphology, crystal structure, thermal properties, wettability, tensile properties, as well as air permeability and water vapor permeability of as-prepared EVOH/Ti3C2 composite fibers were studied. The Ti3C2 is uniformly loaded onto the surface and inside the composite fiber and affects the fiber diameters. Furthermore, The Ti3C2 self-orients along the fiber axis and does not change the crystal structure of the electrospun EVOH fibers, improving the crystallinity and thermal stability of the electrospun EVOH/Ti3C2 fibrous membranes. With the increase in the Ti3C2 concentration in the electrospinning polymer solution, the addition of Ti3C2 not only rapidly improves the wettability of the fibrous membranes, but also enhances their air permeability, compared with the pristine electrospun EVOH fibrous membranes. The experimental results provide theoretical guidance for the preparation of Ti3C2 composite fibers, and also expand the application of electrospun EVOH and EVOH/Ti3C2 fibrous membranes. [ABSTRACT FROM AUTHOR]

Agglomeration is a technological process that is widely applied to obtain powdered products with the appropriate shape and particle size and different physical characteristics and stabilities. The purpose of this research was to study the influences of the composition and storage of powdered infant formulas on their thermal behaviours, as analysed by differential scanning calorimetry (DSC); fatty acid compositions, as determined by gas chromatography; and water activity and water content. This study investigated the influence of the storage time (six months) at temperatures of 20–22 °C and air humidities of 42–45% on powder mixtures and agglomerates. The isotherms of the agglomerates presented a shape and course similar to those of the isotherms of the mixtures from which they were obtained. The agglomeration process affected the stability of the fatty acids in the stored powdered infant formulas. The composition of the fatty acids changed during the storage process. The thermal properties of the powdered infant formulas were not significantly influenced by agglomeration. The compositions of the mixtures and agglomerates influenced the shape and course of the DSC diagrams. Using the DSC method, it was determined whether the fat was a natural component of the powder or it was added in the form of fatty acid preparations. Differences were observed between the shape and course of the DSC curves (heating and cooling) obtained for fresh and 6-month-stored mixtures and agglomerates. [ABSTRACT FROM AUTHOR]

This study aims to explore the viability of adding a hybrid blend of eggshell and banana fibers treated with NaOH to improve the structural characteristics of epoxy composites. In order to determine their appropriateness for different applications, the study includes assessments of mechanical performance, water permeability, and heat transfer properties. Chicken eggshell was used to make calcined eggshell particulate (CEP), and bananas were used to obtain processed banana fibers (TBF). For the creation of bio-composites, NaOH-treated banana fiber (30 wt.%) was integrated into an epoxy matrix with different weight percentages of CEP (like 0, 4, 8, 12, 16, and 20 wt.%) through the hand layup with a vacuum backing technique. Examination of the data revealed that, in comparison to epoxy with no reinforcement, the addition of bio-fillers improved the thermal insulation (4 wt.% of CEP exhibits 0.052 W/mk), water absorption (4 wt.% of CEP produced 5.31%), flexural strength (20 wt.% of CEP exhibit 36.57 MPa), and modulus (12 wt.% of CEP exhibit 300.12 MPa) of the hybrids. This suggests that by lowering the conductivity of the bio-based composites, the inclusion of these bio-based reinforcements improved their thermal insulation ability. The resistance to temperature fluctuations is stronger when there is less thermal conductivity. [ABSTRACT FROM AUTHOR]

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In this work, we present the effect of graphene nanoplatelets (GnPs) modification with ionic liquids (ILs). The textural properties of graphene nanoplatelets (GnPs) used as styrene-butadiene rubber's filler and the thermal properties of the composites obtained with the use of the mentioned fillers were investigated. GnPs were modified with 1-butylpyridinium bromide (BPyBr) and 4-methyl-1-butylpyridinium bromide (BmPyBr) through two different ways. One strategy has been to deposit the filler modifier from the solution. The second one involved the modification of the filler with ionic liquids in bulk during the preparation of elastomer blends. Settlement of the proposed ionic liquids onto the GnPs' surface led to significant changes in the textural characteristics. BPyBr has restricted the filler's microporosity, whereas BmPyBr has caused the formation of a more opened filler structure without the increase in its average pore size. GnPs modified with ILs led to reducing the temperature of vulcanization of SBR compounds and affected the thermal stability of the composites. [ABSTRACT FROM AUTHOR]

Utilizing triethylenediamine (DA), 1,3-propanesultone (PS), whose ring opens during the formation of the dizwiterion-intermediate DA-2PS, and the metal chlorides XCly, where X = Sn(IV), Zn(II),Al(III), Fe(III) and Mn(II), are used for the synthesis of five kinds of acidic metal-based functionalized ionic liquid catalysts ([DA-2PS][XCly]2). Their chemical structures, thermal stability and dual acidic active site were analyzed. We investigated the performance of [DA-2PS][XCly]2 in catalyzing the esterification reaction between 2,5-furandicarboxylic acid (FDCA) and ethylene glycol (EG) to synthesize poly (ethylene 2,5-furandicarboxylate)(PEF). Among the catalysts tested, [DA-2PS][SnCl5]2 exhibited the best catalytic performance under identical process parameters, and the optimal catalyst dosage was determined to be 0.05 mol% based on FDCA. The optimal conditions for the reaction were predicted using response surface methodology: a feed ratio of EG:FDCA = 1.96:1, an esterification temperature of 219.86 °C, a polycondensation temperature of 240.04 °C and a polycondensation time of 6.3 h, with a intrinsic viscosity of 0.67 dL·g−1. The resulting PEF was experimentally verified to exhibit an intrinsic viscosity of 0.68 dL·g−1 and a number average molecular weight of 28,820 g·mol−1. Finally, the structure and thermal properties of PEF were characterized. The results confirmed that PEF possessed the correct structure, exhibited high thermal stability and demonstrated excellent thermal properties. [ABSTRACT FROM AUTHOR]

L‐ and D‐ form oligo(lactic acid)s (OLLA and ODLA) grafted α‐cellulose (OLLA‐g‐cellulose and ODLA‐g‐cellulose) were prepared by the graft polycondensation reaction in C6H5CH3 medium at 130°C and 380 mm of mercury pressure. Para‐toluene sulphonic acid (5 wt% of oligo(lactic acid)) was used as a catalyst whereas potassium persulfate (0.01 wt% of oligo(lactic acid)) was used as a co‐catalyst in the graft polycondensation reaction. OLLA and ODLA with a degree of polymerization (DP) 6–7 used in polycondensation reaction were also prepared by ring‐opening polymerization of L‐ and D‐lactides at 140°C for 10 h with stannous octoate (C16H30O4Sn) as a motivator, L, and D monomer of lactic acids as co‐motivators. FTIR analysis proved the bonding of OLLA and ODLA onto the α‐cellulose surface. The thermal properties of poly(L‐lactic) acid (PLLA) composites were explored by thermal analysis (TG, DTA, and DTG). Degradation, melting, and maximum weight loss temperature of the composites were increased with the increase of grafted cellulose up to 10% and then decreased. TG and DTA results showed that the incorporation of grafted α‐cellulose (grafted cellulose) can improve the thermal properties of PLLA composites. Highlights: Synthesis of oligo(lactic acid)s from L‐ and D‐lactides by ring‐opening polymerization reactions.α‐cellulose extraction and graft modification with oligo(lactic acid)s.Preparation of grafted α‐cellulose composite with PLLA matrix.Evaluation of thermal properties of the grafted α‐cellulose‐reinforced composites. [ABSTRACT FROM AUTHOR]

Piezoelectric ceramics with excellent piezoelectric properties and a high Curie temperature are important for numerous electromechanical devices in a broad range of temperature environments. In this work, the relaxor ferroelectric Pb(Yb1/2Nb1/2)O3 end member was selected to be introduced into a BiScO3-PbTiO3 high-temperature piezoelectric ceramic to reduce the dielectric loss and improve the piezoelectric properties while slightly reducing the Curie temperature. The phase structure and dielectric, ferroelectric and piezoelectric properties of 0.025Pb(Yb1/2Nb1/2)O3-(0.975 − x)BiScO3-xPbTiO3 (0.60 ≤ x ≤ 0.63) ceramics were systematically analyzed, and the best electrical properties were observed in the morphotropic phase boundary region x = 0.61 with d33 = 370 pC/N, kp = 44%, Pr = 33.9 μC/cm2. Importantly, no significant depolarization was observed in the x = 0.61 ceramic from room temperature to 290 °C, demonstrating its good thermal stability and potential applications in a wide range of temperature environments. [ABSTRACT FROM AUTHOR]

Biodegradable polymers have recently become attractive and have been increasingly used as matrix materials to replace fossil plastics due to concerns about the environmental issue. However, their application areas are limited due to their high costs and natural properties. In this study, we fabricated ecofriendly and economical polybutylene adipate terephthalate (PBAT) composites loaded with various concentrations of wood flour (WF) to investigate the effects on the PBAT and WF interfaces as well as the physical properties of the WF/PBAT biocomposites. Then, WF was acetylated with acetic anhydride, and the effect of WF acetylation on the mechanical and thermal properties of the biocomposites were investigated. The results showed that the tensile strength, tensile modulus, flexural strength and flexural modulus increased with WF loading in the composites, and acetylation could not only further increase these properties, but also increase the impact strength and elongation at break. The incorporation of WF would weaken the thermal stability of PBAT, but the thermal stability of the biocomposite could be improved after WF acetylation. The cold crystallization temperature and hydrophobicity of the WF/PBAT samples would be increased with the increasing load of the WF, while the melting enthalpy and the crystallinity of the samples reduced gradually. A morphological analysis of the modified composites revealed that the matrix exhibited greater interfacial interactions with the WF compared to the WF/PBAT. Considering the much lower cost of WF compared to PBAT, the improved properties of WF/PBAT biocomposites will make it economically competitive with other commercial polymers, and these biocomposites should have much wider application areas. [ABSTRACT FROM AUTHOR]

In this work, Ge 8 Sb 2 Te 11 (GST) films with high melting point element Mo doping were prepared by magnetron co-sputtering, and the influence of Mo content on the phase transformation and optical properties of the films was investigated. The results of GIXRD, XPS, and ellipsometry analysis show that Mo will occupy the lattice vacancy, promoting grain growth and accelerating phase transitions. With an increase in Mo content, the phase transition temperature of the films can reach 360 °C, and the amorphous thermal stability of the films can be enhanced by Mo doping. Meanwhile, the optical properties of the films are improved. The optical band gap of Mo-doped films is reduced, the absorption coefficient rises, and the refractive index contrast of GST films with low Mo-doping in the Vis-NIR band is as high as 2.27. This result will make it possible to apply Ge 8 Sb 2 Te 11 thin films in structural color fields and broaden their color spectrum. [ABSTRACT FROM AUTHOR]

Lead-free piezoceramics with superior piezoelectric properties don't meet the requirements of practical applications due to their lower phase transition temperature and poor thermal stability. In the present work, we report a new insight into the effect of glass phase on the piezoelectric, Curie temperature and thermal stability of (Ba 0.85 Ca 0.15)(Ti 0.9 Zr 0.1)O 3 (BCZT) ceramic. Unlike traditional glass materials with more than 80% of B 2 O 3 and SiO 2 as glass formers, our approach is to fabricate a glass phase (Ba 0.85 Ca 0.15)(Ti 0.9 Zr 0.1)O 3 -0.05B 2 O 3 (abbreviate BBCZT) with the same elements and concentrations as the ceramic phase. The ceramics-doped glass samples with the composition [(1-x)BCZT-xBBCZT], where x=(0.0, 0.025, 0.05, 0.075 and 0.1 wt%), were sintered according to the glass phase content. The effect of BBCZT glass composition on the crystal structure, dielectric, ferroelectric and piezoelectric properties of BCZT was investigated in detail. X-ray diffraction revealed that the addition of glass phase causes a defect engineering of the tricritical triple point of BCZT ceramic, where the tetragonal (T) and rhombohedral (R) phases were suppressed by the addition of glass phase and the T-phase has completely vanished at x = 0.05. The maximum value of permittivity (ε = 4102) and converse piezoelectric coefficient (d* 33 = 1150 Pm/V) were achieved for the 0.975BCZT-0.025BBCZT sample at ambient temperature. Furthermore, the diffusion coefficient (γ) and Curie temperature (T c) were observed to increase beyond x = 0.025, indicating enhanced thermal stability of BCZT at high glass content. These results qualify that the addition of (BBCZT) can enhance piezoelectric properties, phase transition temperature and thermal stability of BCZT ceramic which can meet wide requirements of practical applications. [ABSTRACT FROM AUTHOR]

By using the aerodynamic levitation and laser melting technique to well extend the glass‐forming region into the Mg‐rich and peraluminous regime, a series of magnesium aluminosilicate glasses were prepared to investigate the Mg and Al mixed effects on thermal properties, including glass transition temperature (Tg), crystallization behavior, and thermal stability. With the gradual substitution of Mg by Al, Tg exhibits two types of near‐linear rises with different slopes in two compositional regions separated by r = 0.57, where r is equal to the molar ratio of [Al2O3]/([Al2O3] + [MgO]). Moreover, when it comes to other properties, that is, crystallization behavior and thermal stability, this critical point precisely appears at the same r = 0.57. Compared to the slower increase of Tg in Mg‐rich region, the steeper rise of Tg in the peraluminous region is mainly ascribed to the step‐by‐step formation of oxygen triclusters driven by Pauling's second rule. Moreover, the occurrence of the critical point for Tg rise at r = 0.57 rather than the theoretical 0.5 can be seen as a proof of the role of Mg cations partly as a network former. [ABSTRACT FROM AUTHOR]

Silicone foam (SF) is a porous silicone rubber with a lower density, higher elasticity, and good thermal stability. In this work, we selected aluminum spheres and carbon fiber (CF) as thermally conductive fillers to prepare hybrid SF. After optimization, we found that Al and CF hybrid SF (Al-CF-SF) has a higher thermal conductivity (1.37 W·m-1·K-1) than the single-filler filled SF (CF-SF, 1.2 W·m-1·K-1 or Al-SF, 0.52 W·m-1·K-1) under the same filling amount of 60 wt%. The finite element simulation was used further to explore the thermal conductive mechanism of the hybrid SF. Meanwhile, the compressive and tensile modulus of the material (CF-SF) was increased to 10.8 and 3.3 MPa compared with pure SF, respectively, and the mechanical properties were improved. In addition, infrared thermography further demonstrated that Al-CF-SF has a faster heat transfer rate under relaxation and applied pressure. [ABSTRACT FROM AUTHOR]

In this paper, polystyrene (PS)-based reduced graphene oxide (rGO) composites were prepared by mixing PS latex particles with graphene oxide (GO) and the following in-situ reduction. The structure and morphology of PS/rGO composites were characterized, and the effects of rGO content on the dielectric properties as well as thermal stability of PS/rGO composites were investigated. Results showed that rGO sheets armoured on the surface of PS particles and exhibited well dispersion in the PS matrix after hot compression. The introduction of rGO improved the dielectric properties of the composites remarkably. When rGO content was 0.12 vol%, the dielectric permittivity and breakdown strength of PS/rGO arrived at 6.3 at102 Hz and 107 kV/mm, with 50% and 35.4% enhancement compared to the pristine PS. Furthermore, PS/rGO presented better thermal stability than the pristine PS, but the overlapping of rGO sheets in PS matrix induced the instability of dielectric loss with frequency. [ABSTRACT FROM AUTHOR]

The Li-Mn-O system is a crucial constituent of cathode materials used in lithium-ion batteries (LIBs). Numerous research teams have focused on enhancing its electrochemical properties and thermal stability at lower temperatures to develop high-performance cathode materials. However, in the recycling of LIBs in pyrometallurgical processing, the high temperature phase behavior of the Li-Mn-O system is important. Today, there is still a lack of systematic understanding regarding the high-temperature phase behavior of the Li-Mn-O system under well-defined atmospheric conditions, which is highly sought after in the pyrometallurgical process route to increase the recycling efficiency of lithium from spent LIBs. In this study, we investigate the high temperature phase behavior of the pseudo binary system Li2O-MnO under inert atmosphere. Thermal and caloric properties are measured as well as the contact angle at high temperatures to identify the solid-liquid transition. Based on the obtained phase behavior, thermodynamic database of Li2O-MnO within the Calphad framework is developed, where the liquid phase is modelled by the Modified Quasichemical Model (MQM). [ABSTRACT FROM AUTHOR]

Polymer nanocomposites have been of great interest to packaging, energy, molding, and transportation industries due to several favorable properties including a higher resistance to stress and cracking even under flexed conditions, and also a chemical resistance to water, acids, and alkalis. The current work disseminates the studies on the mechanical and thermal properties of the polypropylene HHR102 polymer reinforced with nano dispersoids of silicon dioxide at varied weight fractions. The nanocomposites, fabricated via melt processing followed by injection molding, were tested for tensile strength, % elongation, tensile modulus, and impact toughness. Further, the samples were also subjected to dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA) to determine the dynamic storage modulus and thermal stability. The addition of nano-silica in polypropylene HHR102 resulted in enhanced ductility and well-balanced tensile modulus; however, the tensile strength and impact toughness were found to be decreased. On the other hand, the storage modulus was significantly increased for all nano-silica (NS)-containing polypropylene HHR102 matrices. With the increased nano-silica content, the storage modulus was optimal. Further, with the lower weight loss of 30% and 50%, the thermal stability of the increased silica content PP nanocomposites was much affected. However, it improved at a weight loss of 30% for the lower silica content PP nanocomposite (PP-1%NS). The imbibition was found to increase with the increase in NS. The increase in imbibition is attributed to the micro-voids generated during ageing. These micro-voids act as channels for water absorption. Further, the degree of crystallinity of the nanocomposites was decreased as a result of inhibition by the nano-particles on the regular packing of polymer molecules. The structure–property correlations were explicated based on the achieved mechanical properties. [ABSTRACT FROM AUTHOR]

In our investigation of poly(vinylidene fluoride) (PVDF) films embedded with Au-BaTiO3 (AuBT) nanoparticles, we noted a synergistic improvement in both thermal stability and dielectric properties. PVDF films with varying concentrations of AuBT were expertly fabricated. Remarkably, the films retained their flexibility even at a high volume fraction of filler (fAuBT = 0.5). The predominant phases of PVDF (α, β, and γ) were observed. An increase in fAuBT resulted in a modest decrease in the melting temperature, while simultaneously causing a significant 40% increase in thermal conductivity compared to pure PVDF. The dielectric permittivity reached ∼160 at 1 kHz, while maintaining a loss tangent of ∼0.05. These improvements were attributed to discrete Au growth on BT particles, hindering conduction in PVDF. The rise in dielectric response resulted from interfacial polarization and inherent high dielectric permittivity of BT. [ABSTRACT FROM AUTHOR]

ZIF-L, a metal-organic framework (MOF) material, has a two-dimensional (2D) foliation, a large specific surface area, excellent thermal stability and CO 2 adsorption performance, respectively. In this work, in order to further improve the thermal insulation performance of SiO 2 aerogel composite fabrics, ZIF-L powder was first prepared as a reinforcing particle, and then added to silica aerogel. Finally, SiO 2 /AF/ZIF-L composites were obtained by solution impregnation method. The influence of different ZIF-L concentrations on the insulation performance of composites and their influencing factors were studied. Furthermore, these composites were fully characterized using BET measurement, Instron 5967, precision transient thermal performance tester, infrared thermal imager, insulation performance test, thermogravimetric analyzer, and dynamic thermomechanical analyzer. The results showed that 0.12% SiO 2 /AF/ZIF-L composites had excellent thermal insulation performance, with a thermal conductivity as low as 0.029 W/(m·K). In addition, SiO 2 /AF/ZIF-L composites fabricated by atmospheric drying method had the best thermal insulation performance under the conditions of gel time of 24 h, hydrolysis time of 5 h, and polycondensation pH value of 5–6. [ABSTRACT FROM AUTHOR]

The influences of ethylene-based elastomer (EE) and the compatibilizer agent ethylene-butyl acrylate-glycidyl methacrylate (EBAGMA) on the thermal degradation of PLA/EE blends were evaluated by the thermal degradation kinetics and thermodynamic parameters using thermogravimetry. The presence of EE and EBAGMA synergistically improved the PLA thermal stability. The temperature of 10% of mass loss (T10%) of PLA was around 365 °C, while in the compatibilized PLA/EE blend, this property increased to 370 °C. The PLA average activation energy ( E a ¯ ) reduced in the PLA/EE blend (from 96 kJ/mol to 78 kJ/mol), while the presence of EBAGMA in the PLA/EE blend increased the E a ¯ due to a better blend compatibilization. The solid-state thermal degradation of the PLA and PLA/EE blends was classified as a D-type degradation mechanism. In general, the addition of EE increased the thermodynamic parameters when compared to PLA and the compatibilized blend due to the increase in the collision rate between the components over the thermal decomposition. [ABSTRACT FROM AUTHOR]

Some photosensitive resins have poor mechanical properties after 3D printing. To overcome these limitations, a polyurethane acrylate oligomer (PUA) microsphere was prepared using the Pickering emulsion template method and ultraviolet (UV) curing technology in this paper. The prepared PUA microspheres were added to PUA-1,6-hexanediol diacrylate (HDDA) photosensitive resin system for digital light processing (DLP) 3D printing technology. The preparation process of PUA microspheres was discussed based on micromorphology, and it was found that the oil-water ratio of the Pickering emulsion and the emulsification speed had a certain effect on the microsphere size. As the oil-water ratio and the emulsification speed increased, the microsphere particle size decreased to a certain extent. Adding a suitable proportion of PUA microspheres to the photosensitive resin can improve the mechanical properties and thermal stability. When the modified photosensitive resin microsphere content was 0.5%, the tensile strength, elongation at break, bending strength, and initial thermal decomposition temperature were increased by 79.14%, 47.26%, 26.69%, and 10.65%, respectively, compared with the unmodified photosensitive resin. This study provides a new way to improve the mechanical properties of photosensitive resin 3D printing. The resin materials studied in this work have potential application value in the fields of ceramic 3D printing and dental temporary replacement materials. [ABSTRACT FROM AUTHOR]