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In the domain of personal thermal protection, there is a growing demand for lightweight and efficient ceramic thermal insulation materials. However, conventional ceramic membranes face challenges such as brittleness, structural collapse, and pulverization, hindering their practical application. To address this issue, aluminum hydroxide-enhanced silica-zirconia ceramic membranes (SZ@ANFMs) have been successfully fabricated using electrospinning followed by subsequent calcination processes, and their properties have been comprehensively evaluated. The results demonstrate that SZ@ANFMs exhibit outstanding high-temperature resistance under an alcohol lamp, along with an extremely low thermal conductivity (only 0.041 W/m·K), excellent tensile strength (2.3 MPa), and flexible characteristics. This makes them highly promising in the domain of personal thermal protection. The study builds upon existing research in lightweight and efficient thermal insulation materials, offering improvements and robust support for the further development of personal thermal protection technology. [ABSTRACT FROM AUTHOR]

Porous high-entropy transition metal compounds, an important type of ultra-high temperature material, have attracted increasing attention in the applications of extreme environments due to their low density, good thermal insulation and stable chemical properties. A robust, flame-retardant and high-temperature resistant high-entropy carbonitride (Ti 1/5 V 1/5 Mo 1/5 Nb 1/5 Ta 1/5)(C 0.55 N 0.45) (HECN) porous ceramic was synthesized and thoroughly characterized. It exhibited a porosity of 93.5 %, a compressive strength of 1.3 MPa and a good high-temperature stability up to 1673 K, which, along with its outstanding fire-retardancy, and low thermal conductivity (as low as 0.150 W m−1 K−1 at 298 K), made it a good candidate material for thermal insulation applications in ultra-high temperature environments. Moreover, the Density functional theory (DFT) calculations predict that the [N]/([C]+[N]) ratio in HECN foam affects its lattice thermal conductivity which is decreased by 67 % upon increasing the ratio from 0 to 1/2. [ABSTRACT FROM AUTHOR]

The high production cost and extremely weak mechanical properties of SiO 2 aerogels have been two major challenges hindering its widespread application. Atmospheric pressure drying (APD) has always been regarded as the optimal process to reduce costs. However, traditional APD is cumbersome, still uses a large amount of expensive raw materials, and is extremely immature. In this study, a novel APD was developed, inspired by the wing changes during adult damselfly process. Inorganic silica source/water was used as the raw material, and CO 2 was used instead of low surface tension solvent to stabilize the aerogel skeleton structure in situ, and ultimately aerogel material was obtained. The thermal conductivity of pure aerogels was as low as 0.0264 W/(m·K), the porosity reached 94.7 %, and the preparation cycle was only 28.5 h. The thermal stability of the skeleton structure and the chemical stability of surface were investigated and showed the hydrophobicity to withstand temperatures up to 400 °C. Aerogel composites feature low thermal conductivity of 0.0283 W/(m·K), and prominent thermal insulation properties over a wide temperature range of 50–300 °C. For traditional APD, this method shortens preparation cycle by 1–6 times. Compared with the commercial aerogel, the cost is reduced by 38.2 %, and the process is simple and environmentally friendly under the premise of ensuring excellent performance. [Display omitted] • A novel atmospheric pressure drying of aerogels preparation inspired by biology. • Stabilization of aerogel structures with CO 2 instead of low surface tension solvents. • The preparation cycle time is shortened by 1–6 times, the cost is reduced by 38.2 %. • Thermal conductivity of 0.0264 W/(m·K) and hydrophobic temperature resistance of 400 °C. • Aerogel composites have outstanding thermal insulation and moisture resistance. [ABSTRACT FROM AUTHOR]

Novel methodology introduced to incorporate peroxide in the rubber matrix led to successful development of peroxide cured EPDM insulation based on precipitated silica, a conventional filler. Effect of Silica Filler on the physical, mechanical, thermal, ablative properties and thermal degradation of such an insulation has been recently published. As an outcome of above study, peroxide cured EPDM insulation with 25 PHR of Silica, has been promulgated as potential low density insulation meeting all the requirements of Large Rocket Motor, while having a density as low as 0.997 g/cm3 and Tg as low as −55°C. Effect of aging on mechanical, thermal properties and thermal degradation behavior of low density peroxide cured EPDM insulation has been studied and the findings have been corroborated by FTIR Spectroscopy and morphological Examination by SEM. [ABSTRACT FROM AUTHOR]

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This study examined the thermal reflective properties of composite inorganic coatings applied to various wall types. It evaluated the influence of these coatings on the thermal insulation and reflectivity of the walls. The findings indicate that coating application markedly enhances a wall's thermal insulation capabilities and increases its heat flux reflection ratio. These results offer crucial theoretical backing and practical guidance for the future use of coating technologies in construction. By refining the coating formulations and application processes, the thermal insulation properties of walls can be further enhanced, thus making a significant contribution to building energy efficiency and environmental protection. Consequently, this research provides essential references and insights for advancing coating technology in the construction industry. [ABSTRACT FROM AUTHOR]

Silica aerogel has remarkable properties, particularly its translucence/transparency, extremely low thermal conductivity and density. Due to these properties, it can be used for the thermal insulation of buildings for energy saving, cost saving, and enhanced comfort. In this context, aerogel products such as aerogel blankets have already started to demonstrate their effectiveness in retrofitting projects and the development and adoption of aerogel glazing systems and aerogel-enhanced renders is promising. Other products, for example, through the incorporation of silica aerogel granules in cement and lime renders were obtained, with high thermal insulation properties, to achieve energy efficiency on buildings facades. This research aims to come up with new aerogel particle composition insulation plasters at cost-effective rates for application in building insulation. Their physical apparent mass density, mechanical–flexural and compressive strengths, thermal conductivity, and properties were investigated. As an experimental study, the thermal conductivities of six sets of cement and lime plasters with aerogel particles (0.1–4.0 mm) were investigated and it was concluded that the thermal conductivity of cement and lime plasters with 80% aerogel was 0.2287 W·m−1·K−1, about 3.4 times smaller than the respective value of traditional lightweight plasters of 0.76 W·m−1·K−1, while the cement and lime plasters with less than 40% aerogel showed a thermal conductivity value as low as 0.3172 W·m−1·K−1. It was confirmed that the end product plasters' mechanical qualities included low apparent mass densities, no apparent shrinkage, and mechanical strength values that matched those of the prepared compositions. This suggests that the obtained plasters are suitable for use in both new constructions and renovation projects. [ABSTRACT FROM AUTHOR]

Research into lightweight structural concrete using volcanic tuff is of great importance to the construction industry. These materials have excellent thermal insulation properties, which helps improve the energy efficiency of buildings. A three-factor experimental design was used to build the statistical model. The test methods used were methods for determining the crushability of volcanic tuff, determining the average density, compressive strength and thermal conductivity of lightweight structural concrete. The influence of basalt fiber on the properties of lightweight structural concrete has been determined. The optimal compositions of lightweight structural concrete using tuff have been selected. The compressive strength of lightweight structural concrete reached 32.0 MPa. The average density range is 1754.6–2114.0 kg/m3. Good thermal conductivity values were obtained in the range of 0.653–0.818 W/m·K. The article obtained the optimal compositions of lightweight structural concrete using volcanic tuff as a filler. [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]

As the research for advanced materials suitable for high-temperature uses continues, the need for oxide ceramic micro-nanofibers with outstanding mechanical and thermal properties becomes increasingly important. By incorporating two types of magnesium sources, specifically Mg(CH 3 COO) 2 ·4H 2 O and MgCl 2 ·6H 2 O, into the precursor, a range of fibers made of magnesium silicate ceramics was produced through electrospinning. X-ray diffraction (XRD) analysis verified that the resulting multiple phases included MgO, MgSiO 3 , Mg 2 SiO 4 , and amorphous SiO 2 , with the phase composition being affected by the diffusion reaction of Mg ions. The fibers produced using the dual-precursor method maintained a stable morphology with a uniform and compact structure after undergoing high-temperature treatments ranging from 1000 to 1200 °C. This study is the first to report the tensile strength of magnesium silicate fibrous membranes, which was found to be 1.54 ± 0.27 MPa and 1.21 ± 0.73 MPa after heat treatment at 800 °C and 1000 °C, respectively. Furthermore, these fibrous membranes demonstrated dependable thermal insulation properties within the testing range of 500–1000 °C, along with a low thermal conductivity at room temperature of 0.0301–0.0306 W m−1·K−1. Characterized by their impressive mechanical strength and high temperature stability, magnesium silicate ceramic micro-nanofibers show significant potential for various applications in the targeted field. [ABSTRACT FROM AUTHOR]

In recent years, attention to the realization and characterization of wetsuits for scuba diving and other sea sports or activities has increased. The research has aimed to establish reliable and standardized measurement methods to objectively assess wetsuit quality, particularly focusing on their mechanical and thermal properties. In this work, we describe and compare two different measurement methods for the characterization of neoprene wetsuit thermal resistivity. The first method follows the existing regulations in the field, while the second one, which we are originally proposing in this paper, offers an alternative yet accurate way based on a simplified experimental set-up and easier measurements. In both cases, the wetsuit sample under testing was shaped in the form of a cylindrical sleeve of proper dimensions and wrapped around a phantom containing water at a higher temperature and surrounded by water at a lower temperature. The wetsuit's cylindrical surface allows heat flow from the warmer water on the inside to the colder water on the outside through the wetsuit area. In the first case, a thermal steady state was achieved, with constant heat flow from the phantom to the exterior. This was obtained with a power balance between two homogenous quantities. Electrically supplied thermal heating within the phantom was used to balance the thermal energy naturally flowing through the wetsuit's surface. In this first case, a stable and fixed temperature difference was obtained between the inner and the outer surfaces of the wetsuit sample. In the second case, a thermal transient was analyzed during the cooling process of the phantom, and the thermal time constant was measured, providing the sample thermal resistance once the phantom thermal capacity was known. In both cases and methods, the heat flow and thermal resistance of other elements than the wetsuit must be evaluated and compensated for if they are not negligible. Finally, the thermal resistivity per unit area of the wetsuit material was obtained with the product of the wetsuit sample's thermal resistance and the wetsuit area. The measurements, conducted until now by immersing the phantom in a free surface tank, show that both methods—under stationary and under transient temperature conditions—were valid to assess the wetsuit's thermal resistivity. The stationary method somehow provided better accuracy while involving less well-known parameters but at the expense of a more complicated experimental set-up and additional energy consumption. The transitory method, on the other hand, is quite easy to implement and, after careful characterization of the phantom's parameters, it provided similar results to the stationary one. An uncertainty budget was evaluated for both methods, and they did provide highly compatible measurement results, with resistivity values of 0.104(9) m2·K/W (stationary method) and 0.095(9) K·m2/W (transient method) for the same wetsuit sample under testing, which is also consistent with the values in the literature. We finally propose that the novel method is a valid alternative for characterization of the thermal insulation properties of a scuba diving wetsuit. [ABSTRACT FROM AUTHOR]

Highlights Epoxy resin (EP) is widely employed in power systems and electronic devices due to its low cost and easy processing along with good insulative and adhesive properties. However, EP insulation properties are compromised at elevated frequencies and temperatures because of its negative temperature coefficient effect (NTC) and poor thermal characteristics. In this context, barium strontium titanate (BST‐60), a positive temperature coefficient (PTC) filler, and hexagonal boron nitride (h‐BN), a thermally conductive filler, both surface‐modified with dopamine, are added in EP to simultaneously improve thermal and dielectric insulation properties at high temperatures and high frequencies. This study finds that below the Curie point of BST, the insulating properties of h‐BN fillers significantly contributes to improving insulation properties. Conversely, above the Curie point, the insulating nature of BST fillers leads to an improvement in the insulation performance of composites. Furthermore, at elevated frequency and temperature, the nano h‐BN enhances thermal conductivity of EP by establishing a thermally conductive network, while micro‐BST suppresses the NTC effect of EP by regulating electrical resistivity above the Curie point. The Heywang model elucidates the PTC effect of BST fillers, while a proposed heat conduction‐dissipation mechanism explains the behavior of incorporated fillers at different temperatures. PDA‐modified Ba0.8Sr0.2TiO3 and h‐BN co‐doped epoxy composites are prepared. Negative temperature coefficient effect of epoxy is mitigated by PTC fillers. The optimal wt.% of filler enhances both dielectric and thermal properties. Dielectric properties are explored at high frequencies and temperatures. Optimized epoxy composites are suitable for high‐frequency applications. [ABSTRACT FROM AUTHOR]

SiO2f/SiO2 composites were prepared by compression molding and sintering using short-cut quartz fibers as reinforcement. The effects of fiber volume fraction (15%∼35%) on bulk density, apparent porosity, and mechanical and thermal properties of the composites were investigated. The results indicated that the samples with 25% fiber volume fraction had the best comprehensive performance, with an apparent porosity and compressive strength of 36% and 46.3 MPa, respectively. The flexural strength of the samples was 13.9 MPa, which represented a 90% increase compared to the samples without fibers. It was attributed to the occurrence of fiber debonding and fiber pull-out in the porous matrix. Meanwhile, the residual strength ratio of the samples after 20 thermal shocks was 74.8%. In addition, the average coefficient of thermal expansion was 0.95 × 10− 6/℃ at 300 ℃∼700 ℃ and the thermal conductivity was 0.388 W·m− 1·K− 1 at 800 °C. This approach can satisfy the requirements of low cost, fast preparation of SiO2f/SiO2 composites, which offers the prospect of its application in the integration of load-bearing and thermal insulation. [ABSTRACT FROM AUTHOR]

Ceramic aerogels are promising candidates for high-temperature thermal resistance and thermal insulation materials. However, their application can be restricted by their brittleness when exposed to harsh conditions. Herein, this study has developed a novel synthesis process based on a sol-gel method and carbothermal reduction-nitridation to produce a porous TiN composite aerogel from an organic/inorganic hybrid. The resulting TiN displays a polyhedral particle size of around 30–60 nm with nanoscale pores. In addition, the TiN aerogel demonstrates a high BET-specific surface area of 653.42 m2/g and a very low thermal conductivity of 0.046 W/(m·K). Furthermore, the TiN aerogel composite displays a good thermal difference with no shrinkage and cracks of the morphology during the butane blazing torch at 1300 °C for 10 min under air environment, demonstrating its excellent thermal insulation property and anti-oxidation characteristics. The gas-solid reaction mechanism of TiN aerogel based on the Gibbs free energy calculations is also proposed. [ABSTRACT FROM AUTHOR]

This study investigates the effect of positive temperature coefficient (PTC) fillers, i.e., barium strontium titanate (BST‐60) and nano hexagonal boron nitride (h‐BN) fillers, on thermal and dielectric insulation properties of epoxy (EP). The electrical resistivity, DC breakdown strength, space charge, thermal conductivity, thermogravimetric analysis, and glass transition temperature (Tg) of EP composites were measured. Results indicate that, below curie temperature, the EP composites containing 0.5 and 1 wt% of BST and 5 wt% of h‐BN have superior electrical resistivity, breakdown strength, and thermal conductivity. However, above curie temperature, the EP composites containing 2 and 2.5 wt% of BST and 5 wt% of h‐BN have superior insulation properties than the pure EP and other composites. While the thermal properties of EP improve with an increase in h‐BN loading to 10 wt%, its dielectric properties are slightly compromised due to the presence of tiny defects in the composite material. It is hypothesized that the BST‐60 suppresses the negative temperature coefficient effect (NTC) of EP by regulating the electrical resistivity above the curie point, whereas nano h‐BN enhances the thermal conductivity of EP by constructing a heat dissipation path. The proposed mechanism for charge dynamics along with heat conduction‐dissipation explains the fillers' behavior at different temperatures. Highlights: Analysis of epoxy composites with polydopamine‐modified BST and h‐BN fillers.PTC fillers are used to mitigate the negative temperature effect of epoxy.Optimal fillers wt% improves dielectric and thermal properties.This study shows that optimized epoxy composites can be used for packaging. [ABSTRACT FROM AUTHOR]

This article is a summary of many years of work by the author, in which the thermal properties of various types of insulating liquids, used in power transformers, were evaluated. Recently, esters have been displacing mineral oil. There is a common view that mineral oil has better thermal properties than esters. This claim is supported by comparative results of tests of both materials as a liquid only filling the remaining volume of the transformer. The effect of the type of liquid on the thermal properties of the paper–oil insulation has not been analyzed so far. On this basis, the conclusions formulated may be incomplete. For this reason, the author has analyzed the influence of the type of liquid on both the thermal properties of the liquid filling the remaining volume of the transformer and the paper–oil insulation. It was proved that the more effective liquid filling the remaining volume of the transformer was indeed mineral oil. On the other hand, a more effective electrical insulating liquid, which is an element of paper–oil insulation, is a natural ester. A comprehensive assessment that takes into account both the paper–oil insulation and the remaining transformer volume showed that the natural ester proved to be a slightly more effective electrical insulating liquid than the other analyzed liquids. [ABSTRACT FROM AUTHOR]

Ambient pressure drying (APD) of silica aerogels has emerged as an attractive method adapting to large-scale production. Spring-back is a unique phenomenon during APD of silica aerogels with volume expansion after its shrinkage under capillary force. We attribute the intense spring-back at elevated drying temperatures to a dense structure formed on the surface and the formation of positive internal pressure. Furthermore, an APD-assisted foaming method with an in situ introduction of NH4HCO3 was proposed. NH4HCO3 decomposing at drying temperatures hastened the emergence of positive pressure, thereby increasing the expansion volume. Compared to the previous method, the porosity of silica aerogel increased from 82.2% to 92.6%, and mesopore volume from 1.79 cm3 g−1 to 4.54 cm3 g−1. By adjusting the amount of the silicon source, silica aerogels prepared by the APD-assisted foaming method generated higher volume expansion and lower thermal conductivity. After calcination to remove undecomposed ammonium salts, the hydrophobic silica aerogel with a density of 0.112 g cm−3 reached a mesopore volume of 5.07 cm3 g−1 and a thermal conductivity of 18.9 mW m−1·K−1. This strategy not only improves the thermal insulation properties, but also offers a significant advancement in tailoring silica aerogels with specific porosity and mesopore volume for various applications. [ABSTRACT FROM AUTHOR]

Thermally stable high-performance phenolic resin aerogels (PRAs) are of great interest for thermal insulation because of their light weight, fire retardancy and low thermal conductivity. However, the drawbacks of PRA synthesis, such as long processing time, inherent brittleness and significant shrinkage during drying, greatly restrict their wide applications. In this work, PRAs were synthesized at ambient pressure through a near-net shape manufacturing technique, where boron-containing thermosetting phenolic resin (BPR) was introduced into the conventional linear phenolic resin (LPR) to improve the pore characteristics, mechanical properties and thermal performances. Compared with the traditional LPR-synthesized aerogel, the processing time and the linear shrinkage rate during the drying of the PRAs could be significantly reduced, which was attributed to the enhanced rigidity and the unique bimodal pore size distribution. Furthermore, no catastrophic failure and almost no mechanical degradation were observed on the PRAs, even with a compressive strain of up to 60% at temperatures ranging from 25 to 200 °C, indicating low brittleness and excellent thermo-mechanical stability. The PRAs also showed outstanding fire retardancy. On the other hand, the PRAs with a density of 0.194 g/cm3 possessed a high Young's modulus of 12.85 MPa and a low thermal conductivity of 0.038 W/(m·K). [ABSTRACT FROM AUTHOR]

The development of smart protective clothing will help detect injuries from contact sports, traffic collisions, and other accidents. The combination of ecoflex, spacer fabric, and graphene-based aerogel provides a multifunctional composite. It shows a strain sensitivity of 17.71 at the strain range of 40~55%, a pressure sensitivity of 0.125 kPa−1 at the pressure range of 0~15 kPa, and a temperature sensitivity of −0.648 °C−1. After 50 impact tests, its protection coefficient only dropped from 60% to 55%. Additionally, it shows thermal insulation properties. The compression and impact process results of finite element numerical simulation analysis are in good agreement with the experimental results. The ecoflex/aerogel/spacer fabric sensor exhibits a simple structure, large pressure strain, high sensitivity, flexibility, and ease of fabrication, making it a candidate for smart protective clothing resistant to impact loads. [ABSTRACT FROM AUTHOR]

Foam-forming technique imparts ceramic fiber paper with excellent uniformity, low density, and high porosity, but its strength loss must be compensated. Herein, a flexible and rigid foam-formed ceramic fiber network was manufactured by using different strength improvement methods and simultaneously investigated their strength and thermal insulation properties. Sufficient strength (1136 kPa) was achieved by combining Polyvinyl alcohol (PVA) 2 % and Polyester (PET) 3 %. However, the tensile strength of fiber networks would decrease under the contribution of inter-fiber bonding area reduced when the fiber length was longer than 24 mm. Benefiting from the developed flocculation system (aluminum sol-anionic polyacrylamide-carboxymethylcellulose), the strength of the foam-formed ceramic fiber network was 20 kPa, the retention rate increased from 75 % to 88 %, and the average aggregation factor of fillers in the Z direction was 0.67. By adjusting the ratio and Z-directional distribution of functional fillers, the sintered foam-formed paper with a tensile strength of 1300 kPa and compressive strength of 1000 kPa could be obtained. The thermal insulation performance (thermal conductivity 0.03252 W/(m·K)) was similar to the quartz fiber paper reinforced silica airgel, and the flame resistance was better than the commercialized aluminum silicate wool board. [ABSTRACT FROM AUTHOR]

Workwear clothing is one of the essential personal protective equipment for workers and plays a crucial role in preventing the entry of environmental heat into the body and facilitating thermal exchanges between the human body and the environment. Improving the coating of workwear fabrics while maintaining air permeability is considered an engineering control measure to protect workers in environments with thermal stress. This study aimed to optimize the coating of workwear fabrics with TiO2 nanoparticles to enhance thermal insulation properties and air permeability using the response surface methodology (RSM) and MATLAB. The input variables were the titanium isopropoxide volume and reaction time in the ultrasonic, while the output variables were the coating percent, air permeability, and thermal conductivity coefficients. The morphology of TiO2 nanoparticle and coated fabric (FE-SEM, EDS, FTIR, FTIR-ATR, DLS, and XRD), The intrinsic properties of fabrics (Yarn Count, Abrasion Resistance, Tensile, Tearing Strength), the Water Vapor permeability, Surface wetting resistance, and Durability test were evaluated according to the standard methods. No significant differences were observed in the intrinsic properties between the coated and uncoated fabrics. Increasing the coating percent of fabrics with TiO2 nanoparticles was accompanied with a decrease in the thermal conductivity coefficient and an increase in air permeability. The positive effect of nanoparticle coating is a significant step towards introducing a new generation of smart textiles with the potential to improve thermal insulation properties while maintaining air permeability. This advancement aims to preserve and enhance the health and safety of workers exposed to thermal stress. [ABSTRACT FROM AUTHOR]

Composite materials have garnered considerable interest in the thermal industry on account of their remarkable mechanical properties and thermal resistance. The objective of this research work is to analyse the impacts of integrating porcelain infill particles into basalt fibre-reinforced polymer (BFRP) composites. Particularly, the study aims to evaluate the consequential modifications in critical thermal and mechanical characteristics. The results of mechanical testing indicate that the incorporation of porcelain fillings significantly influences the composite tensile strength, flexural strength, and impact resistance. Additionally, by employing scanning electron microscopy (SEM), significant knowledge is acquired regarding the interfacial bonding mechanisms and microstructural properties of the filler particles, polymer matrix, and basalt fibres. Utilizing dynamic mechanical analysis (DMA), the maximal values of storage modulus (3429 MPa), loss modulus (489 MPa), and damping factor (0.17) are investigated in relation to the dynamic mechanical properties across a range of temperature conditions. The research additionally illustrates enhancements in thermal characteristics, including heat deflection temperature, thermal conductivity, and coefficient of linear thermal expansion, all of which are improved by 37% when porcelain infill is incorporated into the composite. In addition, thermal gravimetric analysis (TGA) examines the degradation and thermal stability properties of the composites over an extensive temperature spectrum, reaching a maximum of 390 °C. The insights derived from this analysis are particularly pertinent to applications involving thermal insulation. [ABSTRACT FROM AUTHOR]

Polymer composites with lightweight, ultralow dielectric constant, excellent thermal insulation and mechanical properties are in high demand in aerospace, transport, wireless communications and other fields. In this work, the three‐dimensional woven Kevlar/glass hybrid composites (3DKGC) with lightweight, high strength, excellent dielectric and thermal insulation properties were obtained with the Kevlar fiber and glass fiber as the raw materials. The results showed that the volume content of air in 3DKGC is over 82% and the volume density is as low as 0.29 g·cm−3, while the compression strength is as high as 7.68 MPa. 3DKGC exhibits an ultra‐low dielectric constant of 1.21. The wave transmission performance of 3DKGC was simulated using the CST software. The simulation results showed that 3DKGC has a return loss of 0.036 and a gain of 0.9982. Moreover, the 3DKGC provides superior thermal insulation than three‐dimensional woven Kevlar composites (3DKC) and conventional polystyrene foams. In summary, this work offers an attractive material that holds significant potential for application in aerospace, wireless communications and other fields where lightweight multi‐purpose composites are required. Highlights: 3D woven Kevlar/glass hybrid composites (3DKGC) were proposed and fabricated.3DKGC exhibits low density of 0.29 g·cm−3 but high compression stress (7.68 MPa).3DKGC possesses outstanding dielectric and thermal insulation properties.3DKGC leverages the benefits of cost‐effectiveness and holistic functionality. [ABSTRACT FROM AUTHOR]

This study utilizes modulation of ionic disorder and electronegativity differences for targeted component design of high-entropy ceramic compositions. A series of novel multicomponent ceramics with the general formula (LaGdYSm) x 2 Yb x 1 Zr 2 O 7 (x 1 +4x 2 = 2, x 1 = 0.6,0.4,0.2,0) were prepared by solid-state reaction. The evolution patterns of their microstructures were analyzed using XRD and TEM, and the anti-sintering ability and thermophysical properties were evaluated. The results confirm that the multicomponent ceramics gradually transform from the coexistence of pyrochlore/fluorite dual-phase structure to pyrochlore structure with the tuning of the size disorder degree. After 50h of exposure to air at 1500 °C, the ceramics retained excellent phase stability. Segregation of La and Yb elements with large differences in radius size occurs, forming a mixture of the La-rich pyrochlore and the Yb-rich fluorite phases. The specimen with the maximum size disorder exhibits the lowest grain growth rate and the greatest thermal insulation properties. Large lattice distortions and sluggish diffusion effects are responsible for the mutual inhibition of grain growth in the two-phase coexistence zone. The thermal insulation properties of the ceramics show well correlated with the degree of the size disorder, further validating the effectiveness of the component design. Meanwhile, the thermal expansion coefficients of prepared ceramic can reach 11.49 × ∼11.58 × 10−6 K−1 at 1000–1100 °C. The customization principles used in this work fill a gap in the compositional design methodology for multicomponent lanthanum zirconate-based high-entropy ceramics. It is essential for developing rare-earth zirconates with tunable thermophysical properties in the area of thermal barrier coatings. [ABSTRACT FROM AUTHOR]

The article describes the achievement and values of the mechanical and thermal characteristics of composite materials with sludge matrix and the insertion of agricultural waste, focusing on the compressive strength and thermal conductivity coefficient. These two characteristics are essential for civil engineering applications. The compressive strength and thermal conductivity coefficient depend significantly on the insertion concentration in the composite material: the compression strength decreases, and the thermal conductivity coefficient increases as the insertion concentration increases. For mud matrix composites and seed husk insert, the compressive strength varies between 0.375 MPa and 2.292 MPa. In the case of sawdust insert, the compressive strength varies between 0.149 MPa and 2.292MPa. These values indicate that composite materials are at the lower limit of strength of building materials, but have good insulating properties due to the low coefficient of thermal conductivity. These features recommend using them for supporting walls in light, floor-free buildings, and for partitions with good thermal insulation properties. [ABSTRACT FROM AUTHOR]

The application of nanotechnology in the field of Buildings and concrete Build is one of the main goals of this article because of the technology's role in enhances the properties of concrete and increasing the efficiency of building materials, as well as in preserving natural resources, reducing environmental pollutants, and increasing the attention that nanotechnology is currently receiving in various fields of science and engineering applications. By partially replacing cement with silica nanoparticles, the current research is focused on investigate the impact of silica nanoparticles (SiO2) on the concrete thermic properties, including specific heat capacity (SHC), thermic conductivity, and thermic diffusivity, in order to produce lightweight concrete with good thermal insulation capabilities. In order to replace a portion of the concrete's weight, nano-silica (NS) was added in percentages of 1%, 2%, and 3%. The results showed that the mixtures including nano-silica had lower thermic conductivity coefficient values, ranging from 0.5 to 0.92 W/m.°C. This indicates that the thermic insulation capacity of nano-concrete increased by 41.8 percent, 53.15 percent, and 65.57 percent, respectively. Furthermore, based on the data, Thermal conductivity coefficient's can be lowest value at a ratio of (3%). As a result, replacing concrete beyond this proportion will result in a reduction in its various qualities. Furthermore, a reduction in the specific thermic ability values was noted in contrast to traditional concrete. [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]

Clinochlore is a major hydrous mineral in subduction zones, and its thermophysical properties at high temperature and pressure are critical to the thermal structures of subduction zones. Here, we used the pulse heating method to measure thermal diffusivity and thermal conductivity of clinochlore at 0.5-4.0 GPa and 298-1373 K. Our results indicate that upon heating, thermal diffusivity and thermal conductivity decrease from ~9.6 x 10-7 m² s-1 to 4.3 x 10-7 m² s-1 and from ~3.5 W m-1 K-1 to 1.9 W m-1 K-1, respectively, before dehydration, but this trend is reversed after dehydration. In general, the pressure derivatives for the thermal transport properties also decrease with temperature before dehydration. Lattice heat transfer is the dominant mechanism before dehydration, but fluid is involved after dehydration. Using our experimental data, we simulated the temperature distribution of subducting slabs containing clinochlore at volume fractions of 0%, 10%, 20%, 50%, and 100%. Our simulations showed that the heat insulation effect caused by the presence of clinochlore could result in an increase in temperature by 30-60 K for the upper part of the subducting slab. [ABSTRACT FROM AUTHOR]

Using a hand lay-up approach, both orange peel and coconut coir fibres are used in particulate form with an epoxy matrix to create partly green biodegradable composites. The findings indicate great opportunities for employing these natural fibres. The thermal conductivity of orange peel and coconut-coir epoxy composites was measured experimentally for various volume fractions of particulate fibres. The experimental findings show that as fibre concentration increases, thermal conductivity decreases. Experimental data are compared to theoretical models to determine the change in thermal conductivity with fibre amount fraction.There was a clear correlation between the hypotheses and the actual results. Regression analysis using Python programming is also done for the prediction of the thermal properties of particulate orange peel and coconut-coir fibre composites. It is observed that coir fibre composites outperformed the orange peel, indicating that the coir fibre composite is a proper thermal insulator that can be used in many industries, like the automotive industry, buildings, and steam pipes, to reduce heat transfer and thereby save a lot of energy. [ABSTRACT FROM AUTHOR]

The integration of waste materials in extrudable cement mixtures has the potential to make the construction industry more sustainable by reducing carbon footprints and developing eco-friendly materials. This along with advancements in 3D concrete printing (3DCP) provides engineering and architectural benefits by reducing material waste and costs. In this paper, the impact of waste incorporation on properties of mortar and concrete is examined. The use of waste materials, such as pumice, coal slag, agricultural lignocellulosic residues, and recycled rubber tyres, to improve thermal insulation and durability of cementitious composites is discussed. In addition, the incorporation of air-entraining admixtures with surfactant activity is explored for their indirect effect on thermal behaviour, pore size reduction, and enhancement in concrete properties. This review includes important topics such as a strength resistance to freezing and thawing, fire resistance, plasticising effect, and delay in cement hydration. These findings highlight the benefits of using diverse waste materials in construction, providing a multidimensional approach to waste management, cost optimization, and enhanced construction materials in the context of 3DCP. [ABSTRACT FROM AUTHOR]

Hollow glass microspheres (HGM) are expected to be used in cryogenic liquid storage tanks as an insulating material with better insulation performance and lower maintenance cost instead of perlite. Obtaining the effective thermal conductivity of HGM can help to improve the insulation performance of cryogenic tanks. Herein, a test system based on the transient plane source method is designed and constructed, and the effective thermal conductivity of six models of HGMs from four suppliers at 200–300 K is measured. The results show that under atmosphere pressure of 200 K, the effective thermal conductivity of HGM is only 25.87–35.84 mW m−1 K−1. The effective thermal conductivity at room and low temperatures is calculated using the derived system of equations for integrated thermal conductivity and radiative heat transfer, with the error of no more than 13% from the current experimental results. The integrated thermal conductivity is still dominant in low pressure and low temperature, and the reduction of the true density contributes to the improvement of the HGM insulation performance. [ABSTRACT FROM AUTHOR]

With the trend of integration and miniaturization of stretchable electronics, thermal management has been a crucial issue. Developing novel materials with high thermal conductivity (TC) and flexibility is urgent. Herein, we report a stretchable polydimethylsiloxane (PDMS)/boron nitride nanosheet (BNNS)@spherical aluminum oxide (Al2O3) composite with high TC and electrical insulation prepared by a two‐step strategy of sucrose‐template and hot‐pressing. An effective foam‐pressing route benefits the composites to form a three‐dimensional thermally conductive networks, improving the in‐plane TC value of the resultant composite to 4.03 W/(mK) at the filler mass fraction of 35.7 wt% and enhancing to 4.66 W/(mK) under 40% stretching ratio. Meanwhile, the composites can be restored to their former state and retain thermally conductive stability with repeated bending and twisting tests. Moreover, the composites were applied in LED with stretching, exhibiting good heat dissipation performance. These results demonstrate this PDMS composite can be potentially utilized as a high‐performance material to solve thermal management problems in flexible electronics. Highlights: The heat conduction network is prepared by sucrose‐template and hot‐pressing.BNNS@P‐Al2O3 fillers are self‐assembled via the electrostatic interaction.The composites exhibit good thermal conduction and superior flexibility.The thermal conductivity of the composite increases after stretching.The composites can retain thermal conductive stability after deformation. [ABSTRACT FROM AUTHOR]

The optimization of structure and thermal properties in 3D-printed insulation materials remains an underexplored area in the literature. This study aims to address this gap by investigating the impact of 3D printing on the thermal properties of manufactured cellular composites. The materials studied were closed-cell foams with a complex cell structure based on the Voronoi cell model, manufactured using incremental technology (3D printing). The influence of the cellular structure of the composite, the type of material used, and the number of layers in the composite structure on its thermal properties, i.e., thermal conductivity coefficient, thermal resistance, and coefficient of heat transfer, was analyzed. Samples of different types of thermosetting resins, characterized by different values of emissivity coefficient, were analyzed. It was shown that both the type of material, the number of layers of the composite, and the number of pores in its structure significantly affect its thermal insulating properties. Thermal conductivity and permeability depended on the number of layers and decreased up to 30% as the number of layers increased from one to four, while thermal resistance increased to 35%. The results indicate that material structure is key in regulating thermal conduction. Controlling the number of cells in a given volume of composite (and thus the size of the air cells) and the number of layers in the composite can be an effective tool in designing materials with high insulation performance. Among the prototype composites produced, the best thermal performance was that of the metalized four-layer cellular composites (λ = 0.035 ± 0.002 W/m·K, Rc = 1.15 ± 0.02 K·m2/W, U = 0.76 ± 0.01 W/m2·K). [ABSTRACT FROM AUTHOR]

Flexible SiC nanowire aerogel felt has excellent foldability, high-temperature resistance, and thermal insulation properties. However, the large-scale and high-efficiency production of SiC nanofiber aerogel felt remains a challenge. In this work, a three-dimensional network-structured short-chopped carbon fiber felt was used as a template for preparing SiC nanowire aerogel felt. The short-chopped carbon fibers were combed and dispersed using an airflow in a carding machine to obtain the desired felt. This method enables rapid and uniform preparation of carbon fiber felt, enhancing the efficiency of SiC nanowire aerogel felt production. The experimental results showed that the aerogel felt was mainly composed of β-SiC nanowires with a density of 5.29 g/cm3. Additionally, the SiC nanofiber aerogel felt exhibited remarkable superelasticity and low thermal conductivity (0.013 W/m·K). This research contributes to the practical application of flexible SiC nanowire aerogel felt in the field of thermal insulation. • Carding machine dispersed carbon fiber. • Fabrication of large size SiC nanofiber aerogel felt. • SiC nanofiber aerogel felt has flexibility and low thermal conductivity. [ABSTRACT FROM AUTHOR]

This paper presents a detailed exploration of the development and characterization of multifunctional dual-purpose woven fabrics for thermal protective clothing. Through this research, 69 woven fabric prototypes have been carefully designed and produced, integrating various raw materials, yarn, and woven fabric construction parameters, with the aim of optimizing thermal protection properties while ensuring comfort and durability. The analysis led to the identification of two optimal woven fabric samples, which, upon further testing, exhibited exceptional dimensional stability, crease recovery, tear resistance, as well as abrasion and water resistance. Furthermore, the thermal properties were evaluated, demonstrating exceptional flame resistance, limited heat transmission, and high thermal insulation. Additionally, the study evaluated dynamic thermal properties, contact conductive heat transfer, air permeability, water vapour resistance, and thermal resistance of two clothing systems constructed from selected woven fabrics. Statistical analysis confirms significant differences between clothing systems, highlighting the influence of yarn composition and fabric structure on thermal performance and comfort, where one system exhibits better thermal insulation characteristics suitable for colder environments while the other excels in breathability for warmer climates. The developed woven fabrics meet high standards for protective clothing against heat and flame, surpassing currently available comparable woven fabrics on the market in terms of efficacy and performance. This research provides insights into the intricate balance between protection, comfort, and durability of woven fabrics, contributing to advancements in protective textile technology. [ABSTRACT FROM AUTHOR]

This study investigates a sustainable coating method for modified expanded polystyrene (MEPS) beads to improve the thermal insulation of lightweight concrete intended for wall application. The method employed in this study is based on a novel coating technique that represents a significant advancement in modifying Expanded Polystyrene (EPS) beads for enhanced lightweight concrete. This study experimentally assessed the energy-saving capabilities of MEPS concrete in comparison to control groups of uncoated EPS beads and normal concrete by analysing early-stage temperature, thermal conductivity, specific heat capacity, heat flux, and thermal diffusivity. The thermal conductivity of MEPS concrete is approximately 40% lower than that of normal concrete, demonstrating its usefulness in enhancing insulation. The heat flux calculated for MEPS concrete is significantly reduced (approximately 35%), and it has a 20% lower specific heat capacity than ordinary concrete, indicating a reduction in energy transfer through the material and, thus, potential energy-efficiency benefits. Furthermore, the study discovered that all test objects have very low thermal diffusivity values (less than 0.5 × 10−6 m2/s), indicating a slower heat transport through the material. The sustainable coating method utilized fly ash-enhanced thermal efficiency and employed recycled materials, hence decreasing the environmental impact. MEPS concrete provides a practical option for creating sustainable and comfortable buildings through the promotion of energy-efficient wall construction. Concrete incorporating coated EPS can be a viable option for constructing walls where there is a need to balance structural integrity and adequate insulation. [ABSTRACT FROM AUTHOR]

The relatively low melting point of a traditional Si bonding layer limits the upper servicing temperature of environmental barrier coatings (EBC). To explore suitable high temperature bonding layers and expedite the development of EBC, first-principles calculation was used to evaluate the mechanical properties and thermal conductivity of HfSi2, HfSi, Hf5Si4, Hf3Si2, and Hf2Si with much higher melting points than that of Si. Among them, HfSi2 has the lowest modulus capable of good modulus matching with SiC substrate. In addition, these Hf-Si compounds have much lower high temperature thermal conductivity with Hf2Si being the lowest of 0.63 W m−1 K−1, which is only half of Si, capable of improved heat insulation. [ABSTRACT FROM AUTHOR]

Among the family of high-quality fiber materials, mullite fiber membrane is a promising one that possesses abilities of both the thermal resistance and oxidation resistance under high temperature. High-purity mullite nanofibrous membranes were prepared by electrospinning method with low-cost aluminum chloride hexahydrate (AC) as the aluminum source. The effects of sintering temperature and AC content on the phase structure, microstructure, thermal and mechanical properties of the mullite nanofibrous membranes were investigated. The results show that the sintering temperature as low as 1000 °C is the very appropriate temperature for obtaining the high-purity mullite nanofibers with smooth surface. The minimum thermal conductivity of 0.029 W m−1 K−1 and maximum tensile strength of 6.11 MPa are gained from the mullite nanofibrous membranes with AC content of 2 mmol. The mullite nanofibrous membranes with excellent properties can be selected as an ideal candidate for thermal insulation and reinforced applications. [ABSTRACT FROM AUTHOR]

The effects of octaphenylsilsesquioxane (OPS), fumed silica, and silica aerogel on the thermal insulation properties of ethylene propylene diene monomer (EPDM) rubber were studied. On this basis, two kinds of fillers with good performances were selected to study the thermal insulation of an EPDM full-formula system. The results show that the addition of fumed silica or silica aerogel had a positive effect on the thermal insulation performance of EPDM rubber and its composite. A 30 wt% silica aerogel can be well dispersed in the EPDM rubber system and with a lower thermal conductivity compared with fumed silica. EPDM composite with 23.4 wt% fumed silica can produce more char residues at 1000 °C than at 500 °C in a burn-through test and formed the compact and porous char at 1000 °C, which had a lowest thermal conductivity. EPDM composite with fumed silica cannot be burned through 1000 °C burning, and comparison with silica aerogel revealed that it achieved the lowest back temperature and had a temperature of 388 °C after 800 s. [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]

The construction industry plays a significant role in shaping our environment and economy. However, it also substantially impacts the environment, including the depletion of natural resources, increased energy consumption, and waste generation. The green building trend has recently gained significant attention in recent years to mitigate the negative impacts of the building industry, focusing on sustainable materials and practices. One of the primary materials used in this field is clay brick, which leads to soil depletion over time. In this context, this study explores the potential of sawdust waste as a partial replacement for clay in brick production, aiming to reduce the depletion of natural resources while enhancing the properties and performance of the produced bricks. The study consists of two main phases: experimental and simulation. In the experimental phase, clay brick samples were produced by adding sawdust at different ratios (1%, 2%, 4%, 8%, and 10% of the raw weight), and various physical and mechanical properties of the produced samples were tested to ensure their suitability for construction use. Also, the thermal properties of the proposed brick were measured to investigate the effect of sawdust addition on brick thermal insulation. Consequently, thermal conductivity and specific heat were measured. In the simulation phase, DesignBuilder software (version 7.0.2) was used to investigate the impact of the proposed material on building envelope's performance and heat gain reduction. All experimental and simulation results were compared with the traditional clay brick measurements, which reveal a significant improvement in brick properties and performance with an increase in comprehensive strength of up to 192.3% and a reduction in energy consumption reaching 11.27%. The study results showed significant improvement in the properties and performance of the produced bricks, indicating the potential of using sawdust waste as a sustainable material for green buildings. [ABSTRACT FROM AUTHOR]

As the demand for sustainable construction practices increases, alternative materials are being explored to reduce waste and carbon emissions. This study investigates the feasibility of utilizing recycled geopolymer binder as a substitute for ordinary sand in the production of geopolymer mortar. The study examines the effects of various replacement rates of recycled geopolymer on the physical, mechanical, and thermal properties of the geopolymer mortar. The results indicate that geopolymer mortar incorporating recycled geopolymer binder as a replacement for ordinary sand exhibits similar mechanical properties to traditional geopolymer mortar, with minor decreases in compressive and flexural strength as the replacement rate increased. The geopolymer mortar also demonstrated lower thermal conductivity than traditional mixes, resulting in increased thermal insulation. These findings suggest that using recycled geopolymer binder as a replacement for ordinary sand in geopolymer mortar production could be a promising approach for sustainable construction practices. [ABSTRACT FROM AUTHOR]

Energy efficient buildings, propulsion components and thermal protection systems require materials with high thermal protective properties. Traditional polymer composites or ceramic materials have limited comprehensive applications because of their poor thermal protective properties or poor processability. Herein, a novel fire resistant and thermally insulating polymer/ceramic hybrid ceramifiable composite was developed based on low temperature sintering principle and foaming on fire strategy. Specifically, the influences of raw materials of low temperature ceramics, such as glass frit, phosphate, etc, on the properties of ceramifiable ethylene-vinyl acetate (EVA) composites were investigated. Its fire resistance and thermal insulation properties were evaluated by simulating different sintering environments. The results show that the ceramifiable composite exhibits the highest improvement in fire resistance because a crystalline phase was formed at high temperatures. Gas evolution from the thermal decomposition of ammonium polyphosphate (APP) and EVA contributes to the formation of the porous structure in ceramic residues. The optimal system can resist above 1000 °C flame for 30 min without disintegration, and the temperature of the unfired side was maintained around 200 °C. The reliability of the strategy was verified by the effective medium theory model. [Display omitted] [ABSTRACT FROM AUTHOR]

The purpose of this study was to model the thermal insulating properties in an exemplary multi-layer layup of space suits utilizing computer simulation techniques and physics and mathematical models. The main system responsible for thermal insulation is the Thermal Micrometeoroid Garment (TMG) material layup. Its structure consists of eight layers with different functions. The utilized textile materials are Rip-Stop-type fabrics, strengthened with the addition of a stronger fiber at fixed intervals. The state variable in thermal problems is the temperature field inside the analyzed TMG. The results obtained from the computer simulation were compared to verification calculations from the mathematical model, which allowed for an assessment of the models' quality and the obtained results. Two numerical models were analyzed in Ansys Workbench software. This enabled an assessment of the model's quality and the possible discrepancies. The modeling of the structure was carried out using the Finite Element Method. The possibility of using this exemplary material layup for a suit was verified using normalized data for an adult in outer space. [ABSTRACT FROM AUTHOR]

Graphene (GN) modified polystyrene (PS) was used to prepare flame retardant PS/GN thermal insulation material, and its mechanical properties and thermal properties were studied. The results show that KH-550 is successfully grafted onto the surface of GN. With the increase of GN content, the mechanical properties and heat resistance of PS/GN insulation materials gradually increase, and the thermal conductivity gradually decreases. When the content of GN is not more than 0.3%, the mechanical properties and heat resistance of PS/GN insulation material increase significantly, and the thermal conductivity increases little. The optimum content of GN is 0.3%, at this time, the compressive strength of PS/GN insulation material is increased by 37.2%, the initial degradation temperature is increased by 29 °C, the mass residue is increased by 0.7%, and the thermal conductivity is 0.037 1 W/(m·K). [ABSTRACT FROM AUTHOR]

Hollow-structured ceramic fibers with multiple components are ideal as lightweight insulation materials. In this study, tetraethyl orthosilicate, boric acid, and zirconia octahydrate were used as raw materials for fabricating SiZrBOC hollow ceramic fibers through coaxial electrospinning. These ceramic fibers exhibit a low thermal conductivity and an excellent temperature resistance. The electrospun SiZrBOC hollow ceramic fibers display a clean and compact morphology with internal folds. Fourier-transform infrared spectroscopy and thermogravimetric analysis (TGA) were used to assess the transformation process and thermal behavior of the hollow ceramic fibers. The results suggest that the incorporation of B promotes the formation of Si–O–B bonds within the system, leading to a maximum yield of 75.49 wt% for the production of the SiZrBOC hollow ceramic fibers. The phase composition and microstructure of the SiZrBOC hollow ceramic fibers were analyzed via X-ray diffraction (XRD) measurements. The pyrolysis at 1000 °C resulted in the appearance of diffraction peaks corresponding to SiO 2 and SiC in the XRD patterns of the SiZrBOC hollow ceramic fibers. Laser thermal conductivity measurements reveal that the SiZrBOC hollow ceramic fibers exhibit a thermal conductivity of only 0.06 W‧m−1K−1 at 25 °C and 0.124 W‧m−1K−1 at 500 °C, indicating a significantly superior thermal insulation performance compared with conventional solid SiZrBOC ceramic fibers. [ABSTRACT FROM AUTHOR]