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Highlights Microfibrillated cellulose (MFC) was uniformly dispersed in high‐density polyethylene (HDPE) using a large amount of surfactant, and composites were prepared after removing the surfactant at different contents. The structural, morphological, thermal, and tensile properties of these composites were systematically investigated. The results demonstrated an asymptotic relationship between the amount of surfactant removed and the number of removal cycles. A negative linear correlation was observed between the surfactant content and the tensile strength, tensile modulus, and storage modulus at −20 °C of the composites, while a positive linear correlation was found with the loss modulus at −20 °C. Excessive surfactant adversely affected the dispersion of MFC, as well as the mechanical properties and thermal stability of the composites. However, when the surfactant content was below 2.8%, its impact on the composite properties was minimal, and the tensile strength, modulus, and thermal stability of the composites were significantly improved compared to neat HDPE. These findings indicate that surfactant pretreatment is an effective strategy for dispersing MFC in non‐polar polymers, and controlling the surfactant content in the final product can effectively tailor the properties of the resulting composites. Confirms the relationship between surfactant content and MFC/HDPE composite properties. Surfactant content showed an asymptotic relationship with removal cycles. Surfactant content and mechanical properties exhibited a negative linear correlation. Surfactant content and thermal stability exhibited a negative relationship. Surfactant content had minor impact when below 2.8%. [ABSTRACT FROM AUTHOR]

Dy3+, Eu3+ co-doped glass ceramics (GCs) containing SrMoO 4 crystalline phase were prepared by melt-curing-crystallization method. The most favorable heat treatment conditions for the glass ceramics were found to be 610 °C/2 h by differential scanning calorimetry (DSC), ultraviolet spectrophotometer (UV–Vis), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The best doping concentrations of Dy3+ and Eu3+ in this glass ceramic were 0.8 % and 0.6 %, concentration quenching caused by dipole-dipole interactions occurs when the content of rare earth ions in GCs continues to increase. The chromaticity coordinates of the Dy3+- Eu3+ co-doped glass ceramics changed from cool white light to warm white light with the addition of Eu3+ concentration. At the optimal doping concentration (0.8 % Dy3+-0.6 % Eu3+), the chromaticity coordinate of glass ceramics is (0.3972, 0.3331), and the related color temperature is 3047 K. The luminescence intensity can still reach about 80 % of room temperature at 180 °C, and its thermal quenching activation energy is 0.233 eV. This suggests that glass ceramics have excellent thermal stability. After adding an appropriate amount of Li+, the crystalline phase of the glass ceramics remained unchanged and the luminous intensity of the glass ceramics increased by a factor of about 1.4 in the same environment. The thermal quenching activation energy of the glass ceramic doped with 0.2 % Li+-0.8 % Dy3+-0.6 % Eu3+ was 0.344 eV. The experimental results indicate that GCs has potential application prospects in the field of solid-state lighting. [ABSTRACT FROM AUTHOR]

The development of high-power piezoelectric ceramics with superior piezoelectric properties and broad temperature usage ranges is vital for the thriving progress of electromechanical applications. However, achieving high piezoelectricity, high mechanical quality factor, and temperature stability often presents a trade-off. In this study, we present an advanced ceramic material with excellent high-power piezoelectric properties and superior temperature stability. The piezoelectric coefficient d 33 reaches 348 pC N−1, the electromechanical coupling factor k p is 54%, the mechanical quality factor Q m is 1501, the dielectric loss tanδ is 0.35%, and the d 33 variation is less than 10% within 25–210 °C in 0.05Pb(Mg1/3Nb2/3)O 3 -0.05Pb(Mn 1/3 Sb 2/3)O 3 -0.9Pb 0.95 Sr 0.05 (Zr 0.48 Ti 0.52)O 3 ceramic. The excellent piezoelectricity is attributed to the enhancement of intrinsic ionic displacement and reversible domains wall motion because of symmetry-conforming short-range distribution of oxygen vacancy, while the high Q m is a result of increased domain size and oxygen vacancy. The outstanding temperature stability is related to the stable non-180°domains structure due to the oxygen vacancy pinning effect. These properties hold great potential for advanced applications, particularly for piezoelectric high-power applications requiring constant d 33 over a broad temperature range. [ABSTRACT FROM AUTHOR]

The red-emitting material SrBaMoO4:0.16Eu3+ was synthesized by using a high-temperature solid-state method. X-ray diffraction (XRD) and fluorescence spectroscopy were employed to analyze the crystal structure and luminescent properties. The results revealed that the sintering temperature had an influence on the crystal structure of the samples, with an optimal sintering temperature of 800℃. SrBaMoO4:0.16Eu3+ synthesized at 800℃ for 6.5 h exhibited a pure crystalline phase of SrBaMoO4. The luminescent intensity of the SrBaMoO4:0.16Eu3+ sample under excitation at 394 nm was tested at different temperatures. When the temperature reached 100℃, the luminescent intensity was 72.11% of the initial intensity, and the temperature reached 175℃, it dropped to 35.27% of the initial intensity. The sample demonstrated efficient excitation by blue light (464 nm), resulting the emission peak at 615 nm corresponding to the 5D0-7F2 transition of Eu3+. The luminescent intensity of the sample was found to increase with increasing Ba2+ concentration, reaching its maximum intensity when the Ba2+ doping concentration x was 0.27, followed by a gradual decreaseat excessive doping concentration, indicating concentration quenching. The CIE coordinates were calculated for the sample under excitation at 464 nm, revealing exhibited the best red emission at the Ba2+ doping concentration of x = 0.27. Additionally, first-principles calculations were used to determine the band structure and density of states of the sample. [ABSTRACT FROM AUTHOR]

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

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

The segment character of polyurethanes (PUs) determines the micromorphology and properties. The effective segment regulation can customize the favorable performance of PUs. Herein, silicon covalent‐modified polyurethanes (MPUs) were prepared by incorporating diphenylmethane diisocyanate (MDI) and diphenyl silanediol (DPSD) into PU molecules as hard segments via a two‐step method. Distinctive microphase separation structures from sheet morphology to radial sheet or withered flower‐like microdomain were formed by adjusting hydrogen bonding of hard segments and post‐treatment techniques. Thus, with the addition of DPSD in hard segments, the thermo‐optic responses for MPUs occurred due to the different microphase evolution under thermal effect. And with the further addition of DPSD, the effect of thermal stimuli on the transmittance gradually weakened. It was very clear that with increasing the temperature, the transmittance of MPUs showed a gradual increase owing to melting the microcrystals or destroying the ordered accumulation of hard segments. Meanwhile, the high mechanical properties were obtained, higher 15 times tensile strength and more than 100 times elastic modulus than those of pure PU as well as the excellent thermal stability. In sum, this study was of great significance for developing new functionalized PU materials. Highlights: Polyurethanes were prepared by inducing modified silicon functionality.The distinctive microphase separation evolution of MPUs was found.Thermal stimuli responses showed a gradual decrease due to different structure.High mechanical properties and thermal stability were also obtained. [ABSTRACT FROM AUTHOR]

Bismaleimide (BMI) resins is widely used in the aerospace field because of its excellent properties, but its poor toughness limits the possibility of its application in a wider range of fields. Therefore, a novel bio‐compound, 4‐(allyloxy)‐3‐methoxy‐N‐(3‐(triethoxysilyl)propyl)benzamide (AMTPM), was designed and synthesized from renewable vanillin, which has Schiff‐base structure, silico‐oxygen bond structure, and allyl structure. The chemical structure of AMTPM has been characterized and validated by Fourier transform infrared (FTIR) and hydrogen nuclear magnetic resonance (1H NMR). It was found that the addition of AMTPM can effectively promote the curing behavior of BD resins (BMI and diallyl bisphenol A (DBA) was mixed and cured at the ratio of 1:0.87, named BD resins). AMTPM can affect the thermal stability and improve the mechanical properties of BD‐AMTPM resins (BD resins modified by AMTPM in different addition), and the detailed discussion was conducted. With the increase of AMTPM content, the thermal stability of BD‐AMTPM resins was deteriorated while the residual weight percentage at 800°C (Yc) was increased. When the content of AMTPM reached 12 wt%, the results showed that Yc achieved the values at a magnitude of 37.57%. Meanwhile, the glass transition temperature (Tg) achieved 320°C. Among the BD‐AMTPM resins system, the BD‐6 wt% AMTPM has the best toughness and mechanical properties. The impact strength was increased by 29.2%, the tensile strength was increased by 22.1% and the elongation at break was increased by 44%. The fracture morphology of BD‐AMTPM resins was also studied by scanning electron microscopy (SEM) to support the mechanical experimental conclusions. This study provides a more environmentally friendly and convenient modifier, which is of great significance for expanding the application of bismaleimide resin. Highlights: A bio‐based modifying agent (AMTPM) was designed and successfully synthesized.AMTPM has both Si‐O and Schiff‐base structures.AMTPM can effectively improve the toughness of BD‐AMTPM resins through impact and tensile tests. [ABSTRACT FROM AUTHOR]

Highlights To improve the subpar lubricating performance of epoxy resin, this paper presents the preparation of a novel bimetallic phyllosilicate featuring a distinctive rice‐granular morphology, which incorporates nickel and iron metal cations through a facile hydrothermal process. These phyllosilicates were then integrated into the epoxy matrix to form composites. A comprehensive analysis of the target product validates the rationality of the synthesis strategy for the as‐prepared rice‐granular bimetallic nickel/iron phyllosilicate, demonstrating a homogeneous hierarchical structure with numerous tiny nanosheets of nickel/iron phyllosilicate grown in situ on the flat surfaces of the rice‐granular metal–organic frameworks. An adequate addition of nickel/iron phyllosilicates allows for excellent dispersion within the matrix and establishes strongly bonded interfaces, steadily increasing the elastic modulus and hardness. Notably, the average friction coefficients decrease from 0.515 for the pure resin to 0.450 for the composites when the filler content reaches 7%, indicating a significant solid lubrication effect. In contrast, adding just 1% nickel/iron phyllosilicate moderately improves wear resistance, elongation at break, and tensile strength. Furthermore, it was found that as the filler content increased, the weight loss rate was reduced by approximately 43.8%, while the residual char increased by 74.2%, significantly enhancing the thermal stability of epoxy composites at high temperatures. This study offers a promising approach to preparing self‐lubricated epoxy composites with favorable mechanical and thermal properties. NiFePS was successfully synthesized via a facile two‐step self‐polymerization. Excellent mechanical properties of composites could be achieved with low content of NiFePS. The friction coefficient and wear rate were lowered remarkably. The friction mechanism was solid lubrication. [ABSTRACT FROM AUTHOR]

Highlights This study investigated the effect of multi‐walled carbon nanotubes (MWCNTs) and reclaimed gypsum of varying contents on the mechanical properties and thermal stability of polypropylene (PP) composite materials. The results indicated that the incorporation of reclaimed gypsum and MWCNTs powder into PP composites could enhance the tensile strength, impact strength, and bending modulus of PP to a certain extent. The above properties of AGY/MWCNTs/PP composites were increased by 14.6%, 131.8%, and 36.2%, respectively, with the impact properties being significantly affected. Univariate analysis of variance revealed that MWCNTs powder and recycled gypsum exerted a significant impact on the mechanical properties of polypropylene composites. Moreover, the initial weight loss temperature of AGY/MWCNTs/PP demonstrated a notable increase, from 318.71 to 398.48°C, while the maximum weight loss temperature exhibited a comparable rise, from 406.85 to 461.54°C. The impact performance and thermal stability of polypropylene composite materials have been demonstrably augmented. A synergistic effect between reclaimed gypsum and multi‐walled carbon nanotubes in the reinforcement of polypropylene composites was demonstrated. This provides a theoretical framework and practical guidance for the design and preparation of high‐performance and recyclable polymer composites. [ABSTRACT FROM AUTHOR]

Levoglucosenone (LGO), a renewable compound obtained from cellulose biomass, has been utilized to prepare novel monomers bearing alkene functional groups. These monomer derivatives of LGO were subsequently cured via ultraviolet (UV)‐initiated radical thiol‐ene “click” chemistry with commercially available multifunctional thiols to obtain colourless, optically transparent cross‐linked thermosets. The monomers prepared in this work are unique due to utilising the internal double bond of the LGO ring during polymerization as part of the cross‐linked network. The thermal and mechanical properties along with the degradation of thermosets containing both ether and ester linkages within the LGO monomers were studied. These thermosets had tensile strengths of 1.3–3.3 MPa, glass transition temperatures between 23.2 and 27.2 °C, and good thermal stability of up to 300 °C. [ABSTRACT FROM AUTHOR]

Background Results Conclusion Fried dough sticks, widely enjoyed in southeast Asia, are made by frying a mixture of wheat flour and water at high‐temperature. With the move towards industrial production, there is an increasing demand for healthier versions. Understanding the key properties of fried dough sticks and how the ingredients interact is crucial for meeting these health‐focused consumer preferences.In this study, the connections between the dough's rheological and thermal properties, alongside the interactions between gluten proteins and the oil content in fried dough sticks, were examined and analyzed at varying gliadin to glutenin mass ratios (Gli/Glu). The results indicated that a general decrease in the viscoelastic properties of the dough was associated with an increase in the Gli/Glu ratio. Furthermore, a heightened concentration of gliadin was observed to augment the mass loss of gluten proteins, thereby engendering a spatially sparse network structure. Additionally, this excessive presence of gliadin precipitated the thermal instability within the dough, necessitating an augmented chemical force to preserve the stability of the gluten network structure.At the Gli/Glu ratio of 5:5, the gluten protein exhibited enhanced thermal stability and minimal mass loss. At this specific ratio, the gluten network was characterized by a comparatively high prevalence of extended gluten films and short‐chain structures, which resulted in the production of fried dough sticks possessing minimal structural oil content. The study provided a theoretical basis for identifying the Gli/Glu ratio as an effective approach to modulate the oil content in fried dough sticks. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In this study, graphene nanoplatelets were applied to polyester fabrics using the knife‐coating method at different concentrations (50, 100, and 150 g/kg). SEM, DSC, and TGA/DTG analyses were performed. The influence of graphene coating on hydrophobicity and surface roughness was examined by water contact angle (WCA) measurement and root mean square roughness, respectively. Abrasion resistance and tear strength tests were also performed. The effect of graphene used as a filler on the flammability of polyester fabric was evaluated for the first time according to the BS 5852 standard. No significant weight loss (only in the range of 0.4%–1.5%) was observed in the graphene‐coated samples even after 100,000 cycles. While the WCA value was 0 for the uncoated fabric, the blind coating and maximum graphene‐coated sample measured 86° and 95°, respectively. The coating process reduced the roughness of the base fabric, and the decrease continued with the increasing graphene ratio. The tear strength values that were 45.5 N in the warp and 53.6 N in the weft direction in the blind coating, increased to 52.2 and 59.1 N, respectively, at the maximum graphene concentration. Graphene coating enhanced thermal stability, increased hydrophobicity, and improved flame retardancy in the test using a smoldering cigarette. [ABSTRACT FROM AUTHOR]

Epoxy resins, known for their excellent properties, are widely used thermosetting resins, but their tendency towards brittle fracture limits their applications. This study addresses this issue by preparing graphene oxide via the Hummer method, modifying it with hyperbranched polyamide ester, and reducing it with hydrazine hydrate to obtain functionalized graphene. This functionalized graphene improves compatibility with epoxy resin. Using a novel two-phase extraction method, different ratios of functionalized graphene/epoxy composites were prepared and tested for mechanical properties and thermal stability. The results showed significant improvements: the tensile strength of composites with 0.1 wt% functionalized graphene increased by 77% over pure epoxy resin, flexural strength by 56%, and glass transition temperature by 50°C. These enhancements, attributed to the improved compatibility between graphene and epoxy resin, demonstrate the potential of functionalized graphene to mitigate the brittleness of epoxy resins, expanding their application potential. [ABSTRACT FROM AUTHOR]

In this paper, a novel composite phase change material (CPCM) is prepared with inorganic PCM through impregnation and dispersion method which can be used for thermal management applications. Inorganic PCMs have high latent heat and good thermal conductivity and are non-flammable, but there exist leakage (shape stability) and corrosion problems. To overcome these issues, a porous structured material is impregnated with the inorganic PCM (disodium hydrogen orthophosphate dodecahydrate). The CPCM is prepared by loading various wt% of expanded graphite and boron nitride nanoparticles with the PCM, and characterization is performed to find the thermal properties and stability. The findings from FTIR and XRD analyses validate both the chemical compatibility and crystalline nature of the samples. DSC thermographs reveal the CPCM5 sample has a latent heat value of 168.05 J/g during the heating process, an encapsulation efficiency of 78.8% and a thermal conductivity of 4.69 W/mK. The thermal stability and resistance to corrosion of the composite samples are also enhanced. The best composite PCM sample is then selected, and subsequently, the thermal performance of the heat sink is experimentally investigated. The thermal performance of rectangular cavity heat sink filled with CPCM5 is the highest for various power sources and temperatures with a maximum enhancement ratio of 6.57. [ABSTRACT FROM AUTHOR]

A lithium‐ion battery separator facilitates lithium‐ion transportation and prevents direct contact between the cathode and anode. Polyimide separators exhibited superior thermal stability and electrolyte wettability. In this study, carboxylated polyimide separators were prepared by electrospinning carboxyl group‐containing monomers. Polyimide separators were prepared with different content of carboxyl group‐containing monomer. Moreover, the thermal property, mechanical property, and electrochemical performance of separators were studied. The carboxylated polyimide separators exhibited lower interfacial resistance and higher ionic conductivity compared with polyimide separators. Moreover, the LiFePO4/Li half‐cell assembled using the carboxylated polyimide exhibited enhanced cycling stability and rate capability. Therefore, carboxylated polyimide separators with superior electrochemical performances are promising candidates for lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Although significant efforts have been undertaken to explore the toughening of epoxy resins, it remains challenges to establish a simple and effective toughening technique which does not compromise its strength, thermal stability and processing performance. In this paper, toluene‐diisocyanate‐trimer (TDI‐T) was utilized to manufacture a novel epoxy‐terminated dendritic modifier TDI‐T glycol diglycidyl ether (TDI‐T GLDE). When the addition of TDI‐T GLDE reaches 20% of the resin mass, the tensile strength, tensile elongation, compressive strength and impact strength were increased by 28.1%, 75%, 24.8%, and 138.0% respectively, compared to E‐51. The thermal properties of the samples have been improved, including an increased glass transition temperature (Tg) from 68.2 to 73.2°C, as well as an increase in the initial decomposition temperature from 240.6 to 257.7°C. The toughening mechanism of TDI‐T GLDE was studied through a combination of mechanical performance tests, thermal performance tests, and resin fracture surface morphology analysis. [ABSTRACT FROM AUTHOR]

Highlights A fluorinated polyimide (PI‐FTD) was synthesized for preparing a thermally conductive PI matrix and composites. Additionally, surface‐treated boron nitride (BN) was incorporated into the PI‐FTD via the solution casting method to form efficient heat paths along the through‐plane direction. The resultant composite demonstrated remarkable characteristics, including an impressive through‐plane thermal conductivity of 3.6 W mK−1, a substantial tensile strength of 69.4 MPa, and excellent thermal stability. When this composite was applied to light‐emitting diodes, it effectively managed heat, reducing the operating temperature by 29°C. The PI‐FTD/BN‐OH composites can potentially improve thermal management in electronic devices. A novel fluorinated polyimide (PI‐FTD) was fabricated. Introducing CF3 functionalities in the PI‐FTD provides high thermal stability. BN‐OH reinforced the thermal and mechanical properties of the composites. The PI‐FTD/BN‐OH composites achieved excellent thermal management. [ABSTRACT FROM AUTHOR]

Phosphors with multifunctional applications have attracted extensive research, especially in thermometer and anti‐counterfeiting fields. Herein, a series of Pr3+‐doped YNbO4 (YNO) phosphors with adjustable photoluminescence and red persistent luminescence (PersL) performances are developed. YNO host exhibits the blue self‐activated luminescence, and the different Pr3+ emission peaks possess various thermal stability properties due to the thermal quenching channel generated by the intervalence charge transfer state between Pr3+ and Nb5+ ions. Two kinds of fluorescence intensity ratio models with high absolute and relative sensitivities are realized to measure the temperature under dual‐wavelength excitation. Moreover, YNO:Pr3+ exhibits the red PersL with a duration of about 120 s upon ceasing the UV excitation light source. The fabricated YNO:Pr3+‐polydimethylsiloxane films display different luminescence patterns with the passage of time after turning off UV light, which can cleverly achieve dynamic conversion. These results demonstrate that YNO:Pr3+ phosphor has potential applications in dual‐wavelength excited thermometry and dynamic anti‐counterfeiting fields. [ABSTRACT FROM AUTHOR]

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) comes from renewable resources, has a reasonable biodegradability rate, and is used in biomedical, food packaging, textiles, and agricultural applications. PLA offers high mechanical strength and the ability to compost, similar to polyethylene terephthalate (PET) and nylon. However, the brittleness of PLA has always limited its usage. Therefore, bio-based plasticizers in the biopolymer matrices can increase flexibility (elasticity), durability, and workability. This study aims to determine the optimal blending ratio for the PLA blended with epoxidized waste cooking oil (EWCO) to enhance the mechanical and thermal properties of PLA/EWCO. The mechanical strength test consists of the hardness test (N/mm2), flexural strength (MPa), and impact energy (kJ/m2) adopted to evaluate the plasticizing characteristics. The thermal stability analysis involves glass transition temperature (Tg) (°C), cold-crystallization temperature (Tcc) (°C) and melting temperature (Tm) (°C). The blending ratio is 97.5PLA/2.5EWCO, 95PLA/5EWCO, 92.5PLA/7.5EWCO and 90PLA/10EWCO. As a result, 97.5:2.5 of PLA/EWCO reduces intermolecular interactions by stimulating more free volume in biopolymer chains' mobility and enhancing the flexibility and elasticity of the PLA blends. Ultimately, the brittleness of PLA decreased with increasing EWCO bio-based plasticizer. [ABSTRACT FROM AUTHOR]

A novel fluorinated diamine monomer (FPMDA ) was synthesized from p-fluorobenzaldehyde and 2, 6-dimethylaniline, and then reacted with pyromellitic anhydride to obtain a fluorinated polyimide (FPI). The structures of the synthesized FPMDA diamine monomer and polyimide were characterized by FTIR, nuclear magnetic hydrogen spectroscopy, and mass spectrometry (MS) ;the thermal properties of the polyimide film were characterized using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The results showed that FPI has excellent solubility in solvents such as DMF, NMP, and THF. FPI also shows good thermal stability, under nitrogen environment, with thermal decomposition temperature Td5% of 550 °C, Td10% of 580 °C, and char yield of 58.7% at 1 000 °C, its glass transition temperature is greater than 400 °C . [ABSTRACT FROM AUTHOR]

Bast fiber-reinforced polymer composites (BFRPs) are grabbing considerable research attention due to their assertive impact on the environment and excellence in biodegradability. Though BFRPs have excellent ecological performance factors, they also lack in some cases, such as lower mechanical, electrical, and thermal properties, due to the significant moisture absorption, minimal thermal stability, and inherent nature of bast fibers. BFRPs exhibit weaker fiber/matrix interfacial adhesion as compared to synthetic fiber-reinforced polymer composites, resulting in lower mechanical properties. Nowadays, a wide variety of fiber and matrix modification techniques are practiced improving the fiber-matrix interaction, which ultimately improves the mechanical properties. Among the fiber and matrix modification techniques, nanofiller integration is the most promising one. This study reviews the impacts of introducing carbon-based nanofillers, particularly graphene and carbon nanotubes (CNT), in diversified BFRPs. The influence of carbon-based nanofillers on the mechanical, electrical, and thermal behavior of BFRPs and their potential prospects are comprehensively reviewed. The paper concludes with the challenges and difficulties in composite processing, along with the techniques for overcoming them. [ABSTRACT FROM AUTHOR]

The traditional high-temperature preparation process of polyimide can cause many problems and limits the wider application in extreme conditions. An important challenge to be solved urgently is the reduction of imidization temperature. In this work, twelve kinds of polyimide films with different chain rigidity were prepared at low temperature of 200 °C, in the absence or presence of imidazole used as the catalyst. The molecular rigidity and free volume were theoretically calculated, and relationship between structure and properties were systematically studied. The results show that imidization reaction under low temperatures is significantly affected by the rigidity of molecular chains. The rigid structure of polyimide is not conducive to the low-temperature imidization, but this adverse effect can be eliminated by adding catalyst, resulting the notably increased imidization degree. The optical and thermal properties can be improved to a certain extent for the chemically catalyzed system, resulting in relatively higher heat resistance and thermal stability. While the mechanical performance could be determined by complicating factors, greatly different from polyimide films prepared by high temperature method. To investigate aggregation structures of films, the effect of chain rigidity and catalyst on the stacking or orientation of molecular chains was further elaborated. This work can contribute to the understanding of chemically catalyzed imidization that is rarely reported in the existing research, and will provide guidance for the low-temperature preparation of high-performance polyimides. [ABSTRACT FROM AUTHOR]

We report a transformative epoxy system with a microalgae-derived bio-binder from hydrothermal liquefaction processing (HTL). The obtained bio-binder not only served as a curing agent for conventional epoxy resin (e.g., EPON 862), but also acted as a modifying agent to enhance the thermal and mechanical properties of the conventional epoxy resin. This game-changing epoxy/bio-binder system outperformed the conventional epoxy/hardener system in thermal stability and mechanical properties. Compared to the commercial EPON 862/EPIKURE W epoxy product, our epoxy/bio-binder system (35 wt.% bio-binder addition with respect to the epoxy) increased the temperature of 60% weight loss from 394 °C to 428 °C and the temperature of maximum decomposition rate from 382 °C to 413 °C, while the tensile, flexural, and impact performance of the cured epoxy improved in all cases by up to 64%. Our research could significantly impact the USD 38.2 billion global market of the epoxy-related industry by not only providing better thermal and mechanical performance of epoxy-based composite materials, but also simultaneously reducing the carbon footprint from the epoxy industry and relieving waste epoxy pollution. [ABSTRACT FROM AUTHOR]

Highlights High temperature shape memory polymers (HT‐SMPs) have great utilization in self‐deployable hinges/morphing structures for space/aerospace, and high‐temperature sensors/actuators for electronics. However, HT‐SMPs have many drawbacks, such as low stiffness, strength, thermal stability, and dynamic mechanical properties. This work aims at improving these properties of highly utilized space grade HT‐SMP, PEKK (polyether ketone ketone), by reinforcing it with low‐cost carbon fibers (CFs), and developing its composite via additive manufacturing. The additively manufactured CF/PEKK composites are annealed at 200 °C (CF/PEKK‐A200) and 250 °C (CF/PEKK‐A250), and for the first time, investigated for shape memory effect (SME). The shape fixity and the shape recovery of the CF/PEKK‐UNA (un‐annealed), CF/PEKK‐A200, and CF/PEKK‐A250 are noted to be 95.97%, 88.95%, and 86.40%, and 88.70%, 92.70%, and 95.19%, respectively with a significant weight saving potential of ⁓21%. Dispersion of CFs in PEKK and suitability of processing parameters (blending, extrusion, and 3D printing) are confirmed through scanning electron microscopy (SEM). Thermal degradation temperature (Td$$ {T}_d $$) of the printed CF/PEKK composite (⁓568 °C) is found to be ⁓3.5% higher than PEKK (⁓549 °C). CF/PEKK‐A250 exhibited the highest storage modulus (4438.23 MPa), ~158% higher than PEKK (1722.3 MPa), while CF/PEKK‐A200 demonstrated the highest tensile modulus (10.9 GPa), which is 138.5% higher than PEKK (4.57 GPa) and 312.88% higher than CF/PEKK‐UNA (2.64 GPa). Moreover, CF/PEKK‐A200 exhibited 237.46%, 138.51%, 127.08%, 61.48%, 32.93%, and 50.35% higher tensile modulus than PEEK, PEKK, PEK, CF/PEK, CF/PEEK, and CF/PEKK composites, respectively, showing great potential to replace them. Printed CF/PEKK composites are investigated for shape memory behavior. The printed composites exhibited outstanding shape memory properties. Printed‐A200 exhibited 138.51% enhanced tensile modulus than pure PEKK. Also, the printed‐A200 showed 313% enhanced modulus than printed‐UNA. Td$$ {T}_d $$ (568 °C) of the printed composites is found ⁓4% greater than pure PEKK. [ABSTRACT FROM AUTHOR]

Highlights The homogeneous dispersion of multi‐walled carbon nanotubes (MWCNTs) in a polymer matrix significantly affects the overall properties of composites. In this study, MWCNTs/epoxy (EP) composites were prepared using DeoxyriboNucleic acid (DNA) as a dispersant. The MWCNTs were uniformly dispersed in a phenalkamine curing agent and crosslinked with an epoxy resin matrix. The non‐covalent functionalization of DNA‐dispersed MWCNTs was confirmed by characterizing both the pristine and DNA‐modified MWCNTs. Additionally, the dispersion state and stability of MWCNTs in the curing agent solution were evaluated. Tensile strength and single‐lap‐shear (SLS) were employed to assess the mechanical properties of the composites. The results indicated that the DNA‐dispersed MWCNTs composites exhibited superior strength and toughness, with tensile and shear strengths of 46.81 and 19.64 MPa, respectively, at optimal ratios. These values represent increases of 68.38% and 50.96% compared to pure EP. Dynamic mechanical thermal analysis (DMTA) revealed that the energy storage modulus of DNA‐dispersed MWCNTs/EP composites increased to 2722 MPa, a 24.7% enhancement over pure EP. Furthermore, the thermal properties of the composites were thoroughly investigated. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) showed that the initial decomposition temperature of the DNA‐assisted dispersed composites rose to 330°C. The macromolecular relaxation of the EP materials occurred at higher temperatures, leading to an increased glass transition temperature. DNA was used to disperse MWCNTs in phenalkamine curing agent. MWCNTs/EP composites were made by crosslinking DNA‐dispersed MWCNTs with epoxy resin. DNA‐dispersed MWCNTs boosted tensile and lap shear strength. Thermal properties improved due to DNA‐dispersed MWCNTs, and increased the energy storage modulus of the composite. [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]

Background: Hyaluronic acid liquid‐core hydrogel beads (HA‐LHB) is a good way for oral intake of HA. However, HA may affect the reaction–diffusion of sodium alginate (SA) and Ca2+ leading to poor mechanical properties, since HA is a polyanionic electrolyte having electrostatic effect and a certain spatial site‐blocking effect. Results: The mechanical properties of HA‐LHB were modified from bathing solution, core solution and secondary calcium bath time. The mechanical properties varied with the SA structure and concentration in bathing solution, where SA with high G (guluronic acid) segment compounded with SA with high M (mannuronic acid) segment at a mass ratio of 7:3 with a 11 g kg−1 concentration showed the best mechanical properties. The secondary calcium bath can greatly improve the mechanical properties due to the tight network formed by bidirectional crosslinking, and 15 min reaction reached the plateau if Ca2+ is sufficient. And the mechanical properties were positively correlated with calcium lactate concentration only at <70 g kg−1 in core solution, but the diffusion of Ca2+ was hindered by the tight gel network at higher concentrations. Moreover, the mechanical properties can be maintained during heat treatment, due to the rearrangement of alginate network structure. Conclusion: Our results suggested that the problem of poor mechanical properties of LHB in the presence of high HA concentration can be avoided by process control, which may broaden the development of HA and popping boba market. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Over the past years, poly(lactic acid) or polylactide (PLA) is commonly researched as a possible replacement for traditional fossil‐based polymers because of its compostability, biocompatibility, and high mechanical properties. PLA has a variety of applications in packaging, biomedical, and structural. However, PLA has limitations, such as high brittleness, low thermal stability, and a slow crystallization rate, which limits the wide range of applications. To overcome these limitations, the literature reports that blending PLA with other polymers, such as poly(ε‐caprolactone) (PCL), is an economically viable approach. Although blending PLA with PCL is considered a feasible approach, the blend system still suffers from immiscibility, depending on the blend composition. This review aims to highlight recent developments from 2014 to date on the processing of PLA/PCL blends, including their composites, with a primary focus on morphological characteristics and mechanical and thermal properties, including their potential applications in various sectors. [ABSTRACT FROM AUTHOR]

Composites are fabricating by reinforcing waste bambara nut shell powder (BNSP) as a bio-filler into an epoxy resin matrix. The composite is fabricated by varying the mass fractions of filler in the range of 5–35 wt%. The effects of bio-filler content on physical, mechanical, and thermal properties are evaluated. The studies reveal that the tensile strength, tensile modulus, flexural strength, and impact strength increased with increasing bio-filler content. The highest mechanical properties of BNSP-loaded epoxy composites are achieved at bio-filler mass content of 15 wt%, whereas hardness increased for 5–35 wt% with peak value at 35 wt%. The water absorption and thickness swelling of the BNSF/epoxy composites increased with increasing bio-filler contents, while the density decreased with an increase in bio-filler content. The TGA results revealed that an increasing bio-filler content decreased thermal stability, whereas the Tg and Tm of the composites increased with increasing bio-filler content. [ABSTRACT FROM AUTHOR]

As a green and recyclable thermoplastic material, polypropylene (PP) has a good application prospect in high voltage cable line. However, its thermodynamic performance is difficult to directly meet the requirements of the cable line, so the PP material needs to be modified to meet the performance requirements. Therefore, based on molecular simulation technology, a nano-CaCO3/PP composite model with doping mass fraction of 3% and 7% nano-CaCO3 and doped grafted silane coupling agent was built, the data of thermal and mechanical properties were calculated, and the changes of its properties were analyzed from a microscopic perspective. The results show that the thermal and mechanical properties of the composites model with grafting number 2 improved the best. In terms of thermal properties, the glass transition temperature (Tg) value increased by 49 K, the free volume fraction decreased by 2.52%, and the thermal conductivity was the highest. In terms of mechanical properties, the rigidity decreased the most, and the toughness improved the most. [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]

Stereolithography (SLA) is a highly versatile additive manufacturing technique that utilizes various ink formulations to fabricate 3D-printed nanocomposite structures with desired properties. Zinc oxide (ZnO) is a promising candidate due to its excellent mechanical and thermal stability, and compatibility with various polymeric matrices. In this work, varying ink formulations containing ZnO nanoparticles, along with employing appropriate post-printing curing parameters to fabricate SLA 3D-printed acrylate-based nanocomposites with improved mechanical and thermal properties, were reported. This study can significantly contribute to expanding its potential use in practical applications such as biomedical and structural applications. [ABSTRACT FROM AUTHOR]

PDMS-based aerogel layers were synthesized as insulation layers by adopting mullite fiber (MF), hollow glass microspheres (HGM) and silica aerogel (SA) as the main fillers, and their loading amounts and content ratios were checked to investigate their effects on the thermal insulation properties in PDMS composites by thermal conductivity, thermal stability, and thermal insulation. The loading amount of nanofillers can significantly influence the insulation-layer performance, and the best performance with the lowest thermal conductivity of 0.0568 W/(m·K) was obtained by 10 wt% loading in PDMS with MF:SA:HGM = 2:2:1, which can achieve a temperature difference (∆T) of 67 °C on a 200 °C hotplate. Moreover, the variation of the filler content ratios can also affect the thermal insulation behavior when the loading amount is fixed at 10 wt%, and the best thermal barrier performance can be found for the sample with more SA as the filler (MF:SA:HGM = 1:3:1). The formed sample had the best thermal stability and thermal insulation property, which can stand a 9 min flame test without burning by butane spray gun, and the backside of the sample showed ∆T > 500 °C for the whole test. [ABSTRACT FROM AUTHOR]

Lithium‐ion batteries are widely used in various industrial and consumer applications. One key point is the thermal stability of these batteries regarding safety. Thermogravimetric analysis and differential scanning calorimetry (DSC) are ideal methods to study the thermal properties of differently charged electrode materials without safety issues associated with thermal runaway tests of the complete cell. This study shows a significant relationship between state of charge (SOC) and power released by the electrode material during the heating process. For the utilized cathode material LixCoO2, a linear relationship is apparent between the decomposition temperature and the decomposition energy, enabling estimation of the SOC. The decomposition temperature of differently charged anode material strongly correlates with the selected heating rate. This study reveals substantial dependencies of the measured power on the utilized crucibles, providing a systematic approach to benchmark the impact of crucible type on observed DSC signals during battery component analysis. [ABSTRACT FROM AUTHOR]

Highlights Increasing the thermal stability and thermal conductivity of polydimethylsiloxane (PDMS) is a crucial issue for thermal applications. This paper focuses on enhancing PDMS's thermal and structural properties by incorporating nanocomposite into the PDMS matrix. An investigation of the impact of rGO‐CaCO3 nanocomposite on the thermal and structural properties of PDMS was performed using Field Emission Scanning Electron Microscopy (FESEM), X‐ray diffraction (XRD), the thermogravimetric analysis and differential thermal analysis (TGA‐DTA), and thermal analyzer tests. It was observed that PDMS doped with rGO‐CaCO3 nanocomposite shows better thermal stability, thermal conductivity, and higher crystallinity. The thermal stability was enhanced significantly by adding a 5% rGO‐CaCO3 nanocomposite, and the initial and end degradation temperatures rose to 492°C and 605°C, respectively. The thermal conductivity of pure PDMS is approximately 0.17 W/mK, whereas a conductive elastomer filled with 5% rGO‐CaCO3 nanocomposite exhibits a thermal conductivity of 0.44 W/mK at a temperature of 20°C. In contrast, the thermal diffusivity is enhanced from 0.13 mm2/s to 0.366 mm2/s. Additionally, the Fourier Transform Infra‐Red (FTIR) spectrum at 1411 cm−1 becomes sharp and noisy, and an additional peak arises at 1398 cm−1, corresponding to the vibrational rocking of the CC bond and COC bond in CaCO3 and rGO. The manuscript focuses on the development of conductive elastomer by incorporating rGO‐CaCO3 doped and its effect on the morphology, structure, and thermal properties of PDMS. The variation in peak intensity observed in XRD attributed to disparities in the crystalline structure of PDMS due to the inclusion of nanocomposite. The thermal degradation range is observed to shift toward the upper end. The degradation temperature at the beginning and end of the process is observed to move to 492°C and 605°C, respectively, upon introducing a 5% rGO‐CaCO3 nanocomposite. The addition of 5% rGO‐CaCO3 filled conductive elastomers shows a significant improvement of approximately 2.6 times in heat conductivity than bare PDMS. [ABSTRACT FROM AUTHOR]

The concurrent enhancement of toughness, electrical conductivity, and thermal stability in polycrystalline diamond composites represents a formidable challenge. Here, a novel diamond-TiC composites (referred to as DTC) with high fracture toughness and conductivity were synthesized through a high-temperature and high-pressure reaction sintering process utilizing two precursors: diamond mixtures containing TiH 2 and Ti-coated diamonds. On the one hand, the inherent bonding and encasing of TiC onto the diamond matrix form a heterogeneous structure, providing high strength and excellent fracture toughness up to 11.6 MPa·m1/2. On the other hand, the established oxygen barrier and current pathway offer a thermal stability of 765 °C and high conductivity up to 837 S·m−1. Remarkably, this rare combination of mechanical, electrical, and thermal properties has been realized within a single material under relatively moderate sintering conditions, thus positioning diamond-TiC composites as a promising ceramic for electrical applications in high-stress environments. [ABSTRACT FROM AUTHOR]

To further increasing the toughness performance of thermoset resins without sacrificing their other properties is still a challenge task. In this study, the soft core–soft shell nanoparticles based on polydopamine‐modified cellulose nanocrystals (P‐CNC) were synthesized and seamlessly integrated with Bisphenol A‐aniline benzoxazine (BA‐a). Notably, the results underscore the remarkable impact of a mere 0.2 wt% of P‐CNC on BA‐a, boosting the impact strength of the modified system to 19.5 kJ/m2. This achievement represents a substantial 140.7% increase compared with pure polybenzoxazine. Moreover, the flexural strength reaches 133.4 MPa, surpassing pure polybenzoxazine by 16.2%. And the modified system exhibits a 10% weight loss temperature (Td10) at 321.7°C, accompanied by a char yield of 27.6%. This holistic approach results in a notable enhancement of the toughness performance while concurrently maintaining the flexural strength and the thermal stability of the modified system. Consequently, the integration of soft core–soft shell nanoparticles emerges as a promising strategy for enhancing thermoset resin properties without undermining their existing exceptional attributes. Highlights: The core–shell nanoparticles were made by dopamine and cellulose nanocrystals.The core–shell nanoparticles can enhance the toughness of polybenzoxazine.Nanoparticle‐matrix interactions and deformation led to improved properties. [ABSTRACT FROM AUTHOR]

A series of halloysite nanotube‐silica (HNTs‐SiO2) nanocomposite fillers were prepared by in‐situ assembly, and a reinforced SiO2/SR composite was obtained by filling them into silicone rubber (SR). The morphology and structural characterization of HNTs‐SiO2 and HNTs‐SiO2/SR and the properties of the HNTs‐SiO2/SR were studied. As a result, the small particle size SiO2 was firmly anchored onto the HNTs surface, and the obtained HNTs‐SiO2 nanofillers were uniformly dispersed in SR. At a 30 phr fixed filler loading, the weakest filler network and the best filler dispersion were obtained when HNTs content in HNTs‐SiO2 was 5%. This resulted in a maximum tensile strength obtained of 6.2 MPa, 1.55 times that of SiO2/SR with the same filler loading, and a maximum elongation at break of 418%, 1.67 times that of the SiO2/SR with the same filler loading, and at the same time the tearing strength and hardness are also improved. Furthermore, the silicone rubber also showed improved thermal stability, with an initial degradation temperature increase of 30°C under a nitrogen atmosphere. Highlights: HNTs–SiO2 nanocomposites were successfully prepared by the self‐assembly method and used as fillers in SR as a new type of reinforcing material.The 1D HNTs act as a barrier to prevent SiO2 aggregation and improved fillers dispersion.The elongation at break and tensile strength of 5% HNTs‐SiO2/SR are 67% and 55% higher than those of SiO2/SR, respectively.The silicone rubber also showed improved thermal stability. [ABSTRACT FROM AUTHOR]

Highlights The over‐loading of heat‐resistant fillers in silicone rubber creates a contradiction between heat resistance and mechanical properties, thus greatly limiting the durability of silicone rubber products in cutting‐edge applications and complex scenarios. To address this issue, silicone rubber was filled with octavinyl polyhedral oligomeric silsesquioxane (POSS) and carbon nanotubes (CNT) and crosslinked with 2,5‐dimethyl‐2,5‐di(tert‐butylperoxy)hexane (DBPMH) in an attempt to obtain composites with excellent mechanical properties and great thermal stability. Optical microscopy and X‐ray diffraction analyses revealed the size of POSS crystals decreased and the characteristic peaks disappeared after the peroxide crosslinked the polymer at elevated temperature. Specifically, silicone rubber composite filled with 0.1 phr POSS and 1.0 phr CNT exhibited a tensile strength of 10.2 MPa and elongation at a break of 450%. Further, the strength and elongation could be kept after thermo‐oxidative aging at 250°C for 32 h. Thermogravimetric analysis results demonstrate that the addition of POSS and CNT into silicone rubber exhibits a synergistic effect, markedly improving the thermal stability of the material. This method provides a valuable reference for manufacturing silicone rubber products that possess both excellent mechanical properties and high thermal stability under extreme working conditions. A novel silicone rubber composite with excellent mechanical properties and thermal stability was prepared. A small amount of octavinyl polyhedral oligomeric silsesquioxane (POSS) and carbon nanotubes exhibited a synergistic effect to improve thermal stability. The dependence of the morphological evolution of POSS crystals in SR on the 2,5‐dimethyl‐2,5‐di(tert‐butylperoxy)hexane and temperature was studied. [ABSTRACT FROM AUTHOR]

In recent decades, fiber membranes have garnered significant attention and found numerous applications across various fields. This work used the electrospinning method to create fiber membranes with cellulose acetate (CA) as a primary polymer material. The characteristics of the fiber membrane, such as mechanical and thermal properties, were investigated by incorporating Pahae Natural Zeolite (PNZ) microparticles into the CA matrix. The fiber membranes' mechanical properties are improved by adding PNZ to the CA matrix, and the CA/PNZ 10% exhibits the maximum tensile strength of 0.97 MPa and elongation at a break of 4.52%. Meanwhile, incorporating PNZ filler into CA fiber membranes significantly enhances their thermal stability. This improvement is attributed to the formation of hydrogen bonds between CA and PNZ, as evidenced by the increasing residue values with higher PNZ content. Specifically, the residue of pure CA membrane fiber is 13.46%, which increases to 44.06% for CA/PNZ 15% fiber membranes. These favorable thermal and mechanical properties of the fiber membranes indicate the promising potential of CA/PNZ-based membranes for filtration applications. [ABSTRACT FROM AUTHOR]

Walnut cake has the potential for use in preparing wood adhesives because of its richness in protein and carbohydrate. In this work, walnut cakes were treated with sodium periodate or potassium permanganate and then were directly used as wood adhesives. Their bonding properties, curing performances, thermal properties, and chemical structures were compared. The results showed that: (1) The oxidation by KMnO4was nonselective. The reaction was very intense, accompanied by the great variability of oxidation degree and degradation degree, enormous viscosity of oxidation products, high coating difficulty, and low content of active aldehyde groups. (2) The oxidation by NaIO4 was selective; the reaction was mild and easy to control. More active aldehydes could be produced and the treatment was beneficial for constructing a spatial net structure of the adhesive. (3) Compared with oxidation of KMnO4, the walnut cake adhesive prepared by NaIO4 oxidation exhibited a more compact structure, a higher crosslinking degree, low curing temperature, and high thermal stability after curing; its bonding performances met the requirements for Class II plywood specified in GB/T 17657(2013). [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]

• The aging process of leather was artificially accelerated. • Changes in secondary collagen structure was analyzed by deconvoluted FT-IR spectrum. • Thermal stability of vegetable-tanned leather was studied by TG/DTG. Leather artifacts, mainly composed of collagen and tanning agents, possess significant historical importance. However, external factors could lead to the aging of such artifacts during preservation. Therefore, it is crucial to examine the impact of various factors on leather aging. In order to know the effects of high temperature and humidity conditions on the changes of leather artifacts, the traditional vegetable tanning agents (chestnut, tara, quebracho, and mimosa) were used to tan the pickled sheepskins to prepare leather artifact model samples. The leather artifact model samples were aged for 0, 2, 4, 8, 16, and 32 days at 80°C and 40–80 % relative humidity (RH). The changes in appearance, structure and thermal stability of the vegetable-tanned leather samples under the synergistic impact of temperature and RH were analyzed using total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), chromatography, and scanning electron microscopy (SEM). The thermal degradation of the samples before and after being tanned with vegetable tanning agents was analyzed using thermal gravimetric analyzer (TGA) analysis. Furthermore, the shrinkage temperature (Ts), tensile strength and elongation at break of the samples were investigated during different aging periods. The study aims to provide valuable insights into the stability of leather artifacts during long-term storage, as well as guidance for their restoration and conservation. [ABSTRACT FROM AUTHOR]

Silicone resins are widely used in various fields because of their excellent high thermal stability. To improve their comprehensive performances, many organic resins have been used for modification of silicone resins. In this article, silicone resins containing phthalonitrile groups were synthesized by the reaction of the silicone resin containing amino groups and 4-(2-oxiranylmethoxy)-1,2-benzenedicarbonitrile. The structures of phthalonitrile-modified silicone resins were characterized by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (1H-NMR). The curing process was characterized by differential scanning calorimetry and FT-IR. Thermogravimetric analysis results showed that the cured modified silicone resins had good thermal stabilities. Dynamic mechanical analysis indicated that they owned high glass transition temperature, suggesting that silicone resins containing phthalonitrile groups have high-temperature resistance. [ABSTRACT FROM AUTHOR]

Purpose: One of the low-cost minerals that can be used as reinforcing filler in polymer industry is pumice powder. Pumice is a highly porous volcanic glass formed during explosive eruptions. This pumice has received significant interest because of its large surface area with various polar groups and can be processed easily. Design/methodology/approach: This study is carried out to investigate the effect of partial replacement of silica (as traditional filler) by naturally occurring pumice powder to improve the thermal and mechanical properties of nitrile butadiene rubber cured with electron beam radiation (doses from 25 to 150 kGy). Findings: The results indicated that the addition of pumice powder increase the tensile strength at lower doses up to 75 kGy (especially at concentration of 5 phr). Besides, an improvement in the thermal stability was attained with the addition of pumice powder. Originality/value: Pumice powder is volcanic-based alumina and silica which is mainly composed of SiO2. It has porous structure which is formed by dissolved gases precipitated during the cooling as the lava hurtles through air. Due to its porous structure, it has low density and high thermal insulation. It also has high temperature and chemical resistance, for these reasons it became preferable material to be used as filler in the plastic and rubber industry. [ABSTRACT FROM AUTHOR]

Cellulose acetate (CA) has found broad applications for many years. However, the development of mechanically strengthened CA materials without losing the processibility in solution remains quite difficult. In this work, novel CA thermosets are reported that can be readily constructed by employing alkyl diboronic acid as a crosslinking agent, which has allowed convenient reconfiguration of CA networks without demanding catalysts or harsh processing conditions. Various properties including thermal stability, creeping resistance, rheological and mechanical strength have been successfully improved by using small amounts (1–5 wt%) of diboronic acid. The dynamic cross‐linked network based on boron chemistry has facilitated solution processing during three times of recycling. Control experiments have shown that alkyl diboronic acid can deliver superior mechanical strength to CA as compared to aryl diboronic acid or single‐arm alkyl boronic acid. Based on the importance of CA materials, this work should be attractive to the design of reprocessible CA thermosets with high performance. [ABSTRACT FROM AUTHOR]

Ceramic fibers are an important thermal insulation material that are not only widely used in extreme conditions, but also play an important role in energy conservation and energy efficiency for sustainable development. However, the practical application of conventional ceramic fibers has a high thermal conductivity in high-temperature environments, which hinders their widespread application. Here, a novel lamellar structured porous SiTiOC/C composite ceramic materials was designed and prepared with excellent thermal insulating properties. The unique microstructure endowed the porous SiTiOC/C composite ceramic materials with a high IR refractive index (93.81%) and an ultra-low thermal conductivity (0.0562 W·m−1 K−1 at 600 ℃). In addition, the porous SiTiOC/C composite ceramic materials not only exhibited excellent mechanical properties (4.46 MPa at 800 ℃), but also demonstrated impressive oxidation resistance and thermal stability. In summary, the proposed porous SiTiOC/C composite ceramic materials provide a reference for the development of high-temperature insulation with good mechanical properties. [ABSTRACT FROM AUTHOR]