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The extensive use of external thermal insulation composite systems (ETICS) using expanded polystyrene (EPS) for building insulation in Germany has resulted in accumulating end-of-life EPS-ETICS. To address limited waste management options and enhance EPS circularity, alternative recycling options like pyrolysis or solvent-based recycling need to be implemented. However, efficient recycling requires ex-ante analyses of the corresponding reverse logistics networks, including all necessary pre-treatment and transport processes. This study aims to develop a decision support system to determine optimal EPS-ETICS waste management by minimising the net present value of the corresponding network design. Our mixed-integer linear optimisation model considers decisions on technology, capacity, and location for pre-processing and recycling facilities as well as on material flow allocation. Applied to a German case study, our model finds pyrolysis and solvent-based recycling economically superior to current waste treatment in waste incineration plants. We present an optimal network design combining central pyrolysis with decentral pre-processing. A scenario analysis shows fluctuating styrene and polystyrene prices might favour solvent-based recycling over the optimal choice in pyrolysis, with minor overall cost differences. Further, legal recycling quotas of at least 40% would be necessary to promote solvent-based recycling and enhance EPS circularity beyond what is achievable through pyrolysis. [ABSTRACT FROM AUTHOR]

The study of insulation degradation processes is crucial for the reliable operation of power equipment and electronic devices. The phase field method has been widely used in recent years to simulate the degradation process of insulation materials. However, the effect of space charge was ignored. In this paper, a novel phase field method based on the bipolar carrier transfer model is suggested. This model can simulate degradation under different temperatures and DC or combined AC/DC voltage. The cases under AC and combined AC/DC voltage at different temperatures are simulated by COMSOL. Methods to ensure model convergence are proposed. The results show that the field strength distribution under a combined AC/DC field is more uniform, especially for negative polarity. For the same voltage form, temperature and breakdown time show an exponential relationship. The results are consistent with those of previous experimental studies, proving the usability of the model. In addition, the processes of initiation, growth, and breakdown stage of the dielectric degradation process, as well as the stagnation period, are explored theoretically. The stagnation time at low temperatures under combined AC/negative DC voltage is long. The research in this paper is useful for insulation optimization design, condition assessment, and longevity prediction. [ABSTRACT FROM AUTHOR]

Static charge on insulating material surfaces may be a source of nuisance and an operational requirement in many devices. It induces a potential that evolves with time due to conduction and polarization processes in the dielectric. Here, we analyze, from a theoretical and experimental point of view, the response of an insulator subjected to a charging pulse, within the frame of linear system theory. The surface potential decay and the return voltage after a brief neutralization, which can be easily measured using an electrostatic probe, usually follow time power laws. We consider here a dielectric following the classical Cole–Cole response function in the frequency domain and derive an exact analytic formula for the potential decay, which involves a Mittag–Leffler function. The relationship between the potential decay and the absorption current when a constant voltage is applied on the dielectric is also analyzed. Experiments on several common insulating materials are analyzed according to this theory, using a numerical simulation with a two-cell model. Return voltage measurements are used to check which materials behave according to the linear model. We underline that an equivalent circuit using constant-phase elements, corresponding to several cells following the Cole–Cole response, can also represent dipolar motions in the dielectric as charge hopping between energy-distributed traps. [ABSTRACT FROM AUTHOR]

Charge injection at metal/polymer interfaces is a critical process in many technological devices, including high voltage capacitors and cables in which polyolefin materials, such as polyethylene (PE) and polypropylene (PP), are often used as insulation materials. We use simulations based on density-functional theory to study charge injection at aluminum/PE and aluminum/PP interfaces. Specifically, we investigate the influence of incorporating a variety of polar chemical impurities at the PE and PP chain ends on electron and hole injection barriers. Crucially, we account for the effect of thermal disorder by considering ensembles of thousands of interface structures obtained from ab initio molecular dynamics trajectories at 373 K. We show that the mean injection barrier can change by up to 1.1 eV for Al/PE and 0.6 eV for Al/PP, as compared to the pristine case, depending on which chemical impurity is introduced. We also show that the spread of injection barriers from thermal fluctuations also depends strongly on the chemistry of the impurity. The observed trends can be understood with a simple model based on thermal fluctuations of the dipole moment density associated with the chemical impurity at the interface. We further verify this model by considering larger interface models with lower impurity densities. Our results demonstrate that small chemical modifications, which may arise from oxidation, for example, have a significant influence on charge injection barriers in metal/polyolefin interfaces. [ABSTRACT FROM AUTHOR]

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]

In this study, novel porous LaPO 4 ceramics possessing closed spherical pores and thin pore walls have been firstly synthesized using the particle-stabilized foaming method. Affected by the calcination temperature together with solid loading, the obtained porous LaPO 4 ceramics exhibit high porosity (81.69–94.21 %), very low thermal conductivity (κ) (0.124–0.398 W m−1 K−1) and relatively high compressive strength (0.886–9.30 MPa). When the calcination temperature and solid loading are 1500 °C and 35 wt%, optimized porous LaPO 4 ceramics achieve a better balance between thermal conductivity (0.160 W m−1 K−1) and compressive strength (2.07 MPa). Based on this, the prediction model for the thermal conductivity is screened and the thermal insulating capability is further verified. This work suggests that porous LaPO 4 ceramics have the potential to be applied as thermal insulation material in the future. [ABSTRACT FROM AUTHOR]

Driven by the global goal of "carbon neutrality", energy conservation, emission reduction and low-carbon development have become important research directions. Transparent thermal insulation materials can effectively shield near-infrared radiation while maintaining high visible light transmittance, making them widely applicable in building energy conservation. In this paper, antimony-doped tin oxide (ATO) and cesium tungsten bronze (Cs x WO 3 , or CWO) are chosen to be composited in order to solve the problems of the poor shielding effect of ATO for short-wavelength near-infrared (NIR) light and the unsatisfactory shielding effect of CWO for long-wavelength NIR light. Therefore, in this study, we employed a one-step hydrothermal method to form a novel CWO@ATO core-shell structure to combine the advantages of both ATO and CWO. By adjusting the composite ratio of ATO and CWO, both the physical and electronic stucutres are effectively tuned to promote the optical modulation in a broad bandwidth. Enventually, the core-shell structured composite exhibit an excellent near-infrared blocking property, surpassing the pure ATO by 27.8 % in the wavelength region of 780∼1500 nm while improving by 14.9 % compared to CWO in the long wavelength between 1500 and 2500 nm. Furthermore, the prepared CWO@ATO core-shell structure repesents near-infrared shielding rate as high as 93.1 % in the full NIR spectrum, and possesses an overall thermal insulation coefficiency (THI) of 9.33 in the full range from 780 nm to 2500 nm, which is substantially larger than that of pure ATO and CWO by a factor of 2.37 and 3.05, respectively. This core-shell structure engineering realizes the utilization of complementary advantages of ATO and Cs 0·33 WO 3 materials, providing a new method to improve the near-infrared performance of energy-saving glass coating, and having broad application prospects in the field of low-carbon buildings. [ABSTRACT FROM AUTHOR]

When a poly(vinyl chloride) (PVC) wire experiences overload failure, the internal structure of the insulation changes to become overloaded insulation and the fire hazard changes. In this study, the thermo‐oxidative degradation behavior of new and overloaded PVC insulation materials was analyzed using coupled thermogravimetric‐Fourier transform infrared spectroscopy (TG‐FTIR). The thermo‐oxidative degradation results show that the first two stages of thermo‐oxidative degradation of PVC insulation are important stages for measuring fire hazard. In addition, the onset temperature of thermo‐oxidative degradation of overloaded PVC insulation was increased. The activation energies of the first two stages of the overloaded PVC insulation increased by 7.7% and 27.0%, respectively, compared to the new PVC insulation. And the reaction mechanism is changed. The FTIR results indicate that the increased amount of volatile organic compounds and CO2 generated during the pyrolysis of the overloaded PVC insulation may result in the generation of more heat and smoke during combustion, thus increasing the fire hazard. [ABSTRACT FROM AUTHOR]

We consider the anomalous, spin, valley, and valley spin Hall effects in a pristine graphene-based van-der-Waals (vdW) heterostructure consisting of a bilayer graphene (BLG) sandwiched between a semiconducting van-der-Waals material with strong spin-orbit coupling (e.g., WS 2 ) and a ferromagnetic insulating vdW material (e.g. Cr 2 Ge 2 Te 6 ). Due to the exchange proximity effect from one side and spin-orbit proximity effect from the other side of graphene, such a structure is referred to as graphene based 'ex-so-tic' structure. First, we derive an effective Hamiltonian describing the low-energy states of the structure. Then, using the Green's function formalism, we obtain analytical results for the Hall conductivities as a function of the Fermi energy and gate voltage. For specific values of these parameters, we find a quantized valley Hall conductivity. [ABSTRACT FROM AUTHOR]

LiCoO2 has become the most widely used cathode material in lithium‐ion batteries because of its high capacity and excellent stability. The high‐temperature solid‐state method is commonly used for the preparation of LiCoO2. However, this method will produce highly penetrating Li2O, which causes spall or fracture of the insulating refractory materials in the kiln. In this study, the corrosion resistance of bubble alumina, mullite, and calcium hexaaluminate (CA6) insulating refractories to LiCoO2 has been thoroughly investigated. Combining the laboratory‐scale interfacial reaction experiments with post‐experimental life cycle analysis of industrial insulating refractories, the interaction between the insulating refractory materials and LiCoO2 after calcination at 900°C for 5 h and the corrosion behavior of LiCoO2 on different insulating refractory materials following heat treatment at 900°C for 5 h every time and repeated seven times are investigated. The corrosion mechanisms are concluded by analyzing the physicochemical composition and macro‐ and micromorphology of the three insulating refractory materials before and after corrosion. The results can provide a basis for the use of insulating refractories in the development of lithium batteries. [ABSTRACT FROM AUTHOR]

These days, the use of natural materials is required for sustainable and consequently plus-, zero- and low-energy construction. One of the main objectives of this research was to demonstrate that pelite concrete block masonry can be a structural and thermal insulation material. In order to determine the actual thermal insulation parameters of the building partition, in situ experimental research was carried out in real conditions, taking into account the temperature distribution at different heights of the partition. Empirical measurements were made at five designated heights of the partition with temperature and humidity parameters varying over time. The described experiment was intended to verify the technical parameters of perlite concrete in terms of its thermal insulation properties as a construction material used for vertical partitions. It was shown on the basis of the results obtained that the masonry made of perlite concrete blocks with dimensions of 24 × 24.5 × 37.5 cm laid on the mounting foam can be treated as a building element that meets both the structural and thermal insulation requirements of vertical single-layer partitions. However, it is important for the material to work in a dry environment, since, as shown, a wet perlite block has twice the thermal conductivity coefficient. The results of the measurements were confirmed, for they were known from the physics of buildings, the general principles of the formation of heat and the moisture flow in the analysed masonry of a perlite block. Illustrating this regularity is shown from the course of temperature and moisture in the walls. The proposed new building material is an alternative to walls with a layer of thermal insulation made of materials such as polystyrene or wool and fits into the concept of sustainable construction, acting against climate change, reducing building operating costs, improving living and working conditions as well as fulfilling international obligations regarding environmental goals. [ABSTRACT FROM AUTHOR]

This study aims to improve the fire resistance of geopolymers by adding thermal insulation materials. These additives help the material perform better at high temperatures. Previous research focused on using fly ash, metakaolin, and zeolite in geopolymer composites. This study looks at how porous additives affect compressive strength and whether non-destructive testing can measure damage after heat exposure. Four temperature tests were set: 400 °C for 60 min, 400 °C for 120 min, 800 °C for 60 min, and a maximum of 658 °C for 120 min. The results showed that the compressive strength and ultrasonic pulse velocity (UPV) dropped as the temperature increased, with a sharp decrease at 800 °C. Unmodified samples broke apart at high temperatures, while modified samples lost 40% to 70% of their strength. The study confirmed that a dense, amorphous matrix improves heat resistance, even with porous additives like fly ash. A link between UPV and compressive strength was found, suggesting non-destructive testing could be useful for checking structural integrity after a fire. [ABSTRACT FROM AUTHOR]

The current study investigates the effect of adding a low-cost biomaterial (sawdust biomass) to kaolinite clay on the properties of insulating refractory materials. Natural kaolinite clay from NW Tunisia has been selected for porous ceramic preparation due to its high alumina content (23.64%) with low impurities, especially iron and alkaline oxides. For this study, a set of cylindrical samples were prepared from mixtures of Tabarka clay with different proportions of sawdust (10, 15 and 20%). Those green specimens were pressed and sintered to 1350 °C for 2h. Experimental data showed that the increase in sawdust proportion increased the open porosity from 24 to 35%. SEM images showed higher important porosity with higher biomass addition. Similarly, bulk density and compressive strength decreased to 1.65 g/cm³ and 17 MPa, respectively. Mullite phase was also generated by the abundant alumina and silica in the raw feed. Several ceramic specimens were also manufactured under optimal conditions: sawdust (20%), pressure (10 kN), and sintering at 1200, 1250 and 1300 °C. The obtained ceramics showed higher porosity (57%), but lower bulk density (1.13 g/cm³). These are the required standards for silica-alumina insulating materials, confirming the possible valorization of kaolinite clay from Tunisia for refractory insulating ceramic. [ABSTRACT FROM AUTHOR]

As part of the energy transition and global environmental problems, improving the energy efficiency of buildings has become an imperative aspect for the architecture, engineering and construction industries. Furthermore, the energy performance of a building depends directly on the quality of its thermal envelope and the insulation material applied. Therefore, the main aim of this study is to assess by means of simulations the impact of ecological insulation materials on thermal comfort and energy efficiency in the case of a residential building in a Mediterranean climate. The results of the simulation show that optimising envelope design parameters can reduce annual energy loads for heating and for cooling. The most efficient strategies for achieving this reduction involve the use of ecological thermal insulation of external walls, optimising glazing settings and use of efficient shading devices. [ABSTRACT FROM AUTHOR]

Composite materials with high heat dissipation and acceptable insulating properties are being developed. Minimizing filler contacts in the composite and is crucial for composite insulating materials. Here, an electrostatic adsorption method was used to prepare thermoplastic polyimide (tpPI) / orientation micro‐sized hexagonal boron nitride (h‐BN) composite insulating materials. Then the effects of h‐BN particle size on the thermal conductivity and DC breakdown strength were investigated. Additionally, the finite element method was used for heat conduction analysis and the results were compared to the measurements. The particle size of the h‐BN significantly influences the dc breakdown strength and the thermal conductivity. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

A resilient, flame-retardant and high-temperature resistant high-entropy carbonitride aerogel (HECNA), (Ti 1/5 Cr 1/5 Mo 1/5 Nb 1/5 Ta 1/5)(C 0.56 N 0.44), was successfully synthesized and thoroughly characterized. It exhibited a porosity of 93.9 %, a compressive strength of 1.1 MPa and a remarkable stability at temperatures up to 1673 K, which, along with its outstanding fire-retardancy, and low thermal conductivity (as low as 0.149 W·m−1·K−1 at 298 K), made it a good candidate material for thermal insulation applications in demanding environments. Density functional theory (DFT) calculations indicate that the [N]/([C]+[N]) ratio in HECNA affects its lattice thermal conductivity, with a potential 83 % reduction achievable by increasing the ratio from 0 to 1/2. This aligns with experimental findings, underscoring the substantial impact of elemental composition of HECNA on its thermal insulation performance. [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]

Compatibility of polycarbonate (PC) and polymethyl methacrylate (PMMA) alloys was improved by using a transesterification catalyst (SnCl2·2H2O). Modified PC/PMMA alloys exhibit single Tg, and their initial island phase existing in the SEM were transformed into uniform surface. Besides, the transmittance of the modified alloys was increased from original 40% to 85%. Moreover, PC/PMMA alloys and PC foams with micro‐cellular and nano‐cellular structures were prepared by solid‐state CO2 foaming in the presence of transesterification catalyst. Distinctively, there are obvious nano‐cellular structures existing in the PC samples, but no related nanostructures were found in PMMA samples, after treated by same amount of catalyst and foaming process for pure PC and PMMA matrix. Furthermore, the effects of foaming temperature and segment structure on their foaming behavior were also studied. Additionally, a uniaxial stress experiment was conducted at a specific temperature to simulate the biaxial stress during the foaming process for discovering the mechanism of nanopore formation. Therefore, the concept of nano‐cellular structures will point out a direction for the development of high‐performance, heat insulation PC materials of the next generation. Highlights: Transesterification catalysts enhanced compatibility between PC and PMMA.Nanopore structures were successfully constructed in PC foams.Segment stretching was the main reason for the formation of nanopores. [ABSTRACT FROM AUTHOR]

The need for green thermal insulation materials, such as biopolymer aerogels, has become increasingly critical in the face of escalating environmental concerns and the urgent push toward sustainable practices. The unique characteristics of biopolymer aerogels, coupled with their environmental benefits, position them as potential disruptors in the insulation industry. As research continues, addressing challenges and refining fabrication techniques will likely lead to wider adoption of these materials, contributing to a greener and more energy‐efficient built environment. This review presents the latest developments concerning the properties and versatile applications of biopolymer‐based thermal insulators as a new type of green materials. It comprehensively examines the fundamental principles of thermal insulation, factors that influence its efficacy, and the compatibility and mechanisms underlying bioaerogels within this context. The review also addresses the latest works about the utilization of different biopolymer aerogels in different thermal insulation applications and critically assesses the obstacles currently faced by biopolymer‐based aerogels and elucidates potential avenues for future advancement. Highlights: Biopolymer aerogels offer a sustainable alternative in insulation.Challenges in production limit current aerogel adoption rates.Latest advancements highlight aerogels' versatile insulation applications.Future research aims to enhance biopolymer aerogel technology and use. [ABSTRACT FROM AUTHOR]

Phenolic aerogels based on resorcinol‐formaldehyde (RF) are among the best thermally insulating materials. However, the hydrophilicity inherent to the free phenolic moiety of RF gels generally limits their actual range of applications. Prior efforts to render phenolic gels hydrophobic are restricted to post‐synthetic functionalizations of hydrophilic gels, processes that are often limited in efficiency, scope, and/or longevity. Here, an acid‐mediated conversion of 1,3,5‐trimethoxybenzene with formaldehyde is reported, yielding monolithic trimethoxybenzene‐formaldehyde (TMBF) aerogels and xerogels with low density (0.11–0.30 g cm−3), high porosity (74–92 %), inner surface areas (SBET) of up to 284 m2 g−1, and thermal conductivity of 34.5–43.9 mW m−1 K−1. For a monolithic xerogel based on TMBF xerogels an unprecedently low thermal conductivity of 34.5 mW m−1 K−1 could be achieved. In addition, all TMBF gels are thermally stable (degradation >280‐310 °C) and highly hydrophobic (water contact angles 130°–156°). As such, TMBF serves as a new class of inherently hydrophobic aerogels and xerogels and useful complement to RF materials. [ABSTRACT FROM AUTHOR]

Soft magnetic composites (SMCs) are key materials in electronic devices. Conventional SMCs incorporate too much insulating material in order to reduce eddy current loss at high frequency, resulting in severe magnetic dilution and demagnetization field, which leads to deterioration of the magnetic performance. In this paper, ZnO precursor is homogeneously deployed on the surface of FeSiAl, which in situ generates a thin and dense Al2O3 layer on the surface of FeSiAl through the interfacial solid phase reaction between Al and O atoms during annealing process. Meanwhile, ferromagnetic ZnO layer is simultaneously obtained due to the loss of O. The formed Al2O3/ZnO layers effectively reduce power loss and endow high frequency stability with less influence on effective permeability. Finally, FeSiAl/ZnO‐0.4% SMC exhibits low power loss of 83.2 mW cm−3 (50 mT/100 kHz), high effective permeability of 92, and cut‐off frequency as high as 40 MHz. This study provides an efficient route for high performance SMCs and broadens high frequency application of soft magnetic devices. [ABSTRACT FROM AUTHOR]

The global climate change is mainly caused by carbon dioxide (CO2) emissions. To help reduce CO2 emissions and conserve thermal energy, sustainable materials based on flexible thermal insulation are developed to minimize heat flux, drawing inspiration from natural systems such as polar bear hairs. The unique structure of hollow double‐shell fibers makes it possible to achieve low thermal conductivity in the material while retaining exceptional elasticity, allowing it to adapt to insulation systems of any shape. The layered system of porous mats reaches a thermal conductivity coefficient of 0.031 W∙m⁻¹∙K⁻¹ and enables to reduce the heat transfer. The results achieved using scanning thermal microscopy (SThM) correlate with the simulated heat flow in the case of individual fibers. This research study brings new insights into the energy efficiency of domestic environments, thereby addressing the growing demand for sustainable and high‐performance insulation materials for saving energy loss and reducing pollution footprint. [ABSTRACT FROM AUTHOR]

In the process of the development of the ceramic industry, a large amount of ceramic solid waste is generated, and how to make high‐value reuse of ceramic solid waste has also become a problem of common concern. In this article, a new method of making porous thermal insulation materials reusing waste electric porcelain was successfully developed. In this work, a porous light refractory with bulk density of 0.99 g/cm3 and apparent porosity of 59% was prepared by the novel method. Which room temperature flexural and compressive strengths are 11.52 MPa and 1.84 MPa, respectively. These properties makes the waste electric porcelain‐based porous light refractory can be applicated as lightweight heat insulation materials for high‐temperature kilns, high‐temperature catalyst carriers, high‐temperature phase‐change heat storage support materials, etc. which will create higher application value and research significance. [ABSTRACT FROM AUTHOR]

The thermal protection system (TPS) are an indispensable component of aerospace vehicles that can withstand harsh aerothermal conditions during the reentry process. Recently, the sandwich structures of TPS have been widely used to meet the development trend of structure-performance integrated design. In this study, a TPS with a sandwich structure based on Al 2 O 3 aerogels reinforced by SiC nanowire are proposed. The Al 2 O 3 /SiC composites aerogels are synthesized via the low-cost method, including sol-gel, freeze-casting and high-temperature treatments processes. The microstructure, phase composition, thermal insulation and compressive resistance of composite aerogels at different SiC nanowires content are investigated in detail. The resulting Al 2 O 3 /SiC composites aerogels, exhibiting better compressive strength and thermal stability with the increase of SiC nanowires content, achieve the purpose of being an excellent thermal insulation material of TPS at high temperature. The characterization of thermal insulating performances of the TPS are also evaluated by the oxyacetylene torch testing. The TPS shows extraordinary high-temperature resistance, and the average linear ablation rate and mass ablation rate are 0.0032 mm/s and 0.005 g/s, respectively, which can satisfy the requirement of TPS for aerospace vehicles under ultra-high temperature conditions. [ABSTRACT FROM AUTHOR]

Zirconium oxide (ZrO 2) porous ceramic shows promising application in construction and industry due to its remarkable chemical stability, corrosion resistance, oxidation resistance, and thermal resistance. While the construction of stable anisotropic ZrO 2 porous ceramic is still a challenge. In this study, we report an anisotropic ZrO 2 porous ceramic using bacterial cellulose nanofiber (BCNF) as a framework and zirconium oxychloride octahydrate as the zirconium source. ZrO 2 porous ceramic was achieved through directional freezing, vacuum freeze-drying, and calcination processes. ZrO 2 arrangement relies on the BCNF framework and retains the three-dimensional (3D) structure after the calcination of BCNF. Results reveal that the resulting ZrO 2 porous ceramic possesses a well-ordered anisotropic network structure, exhibiting excellent stability at 1100 °C in air. Benefiting from the anisotropic structure, ZrO 2 porous ceramic exhibits high load-bearing capacity in the longitudinal direction, and thermal insulation with a significant temperature difference of approximately 50 °C between transverse and longitudinal heat transfer. It also keeps stable in extreme conditions including low temperature and acid solution. These unique properties make it an ideal insulation material in extreme environments where the protection of structures with complex shapes and variable dimensions is critical. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper proposes a novel strategy to fabricate porous calcium hex-aluminate (CA 6) ceramics using CaCl 2 -KCl as reactive medium. Effects of CaCl 2 -KCl content and sintering temperature on microstructure and properties of porous CA 6 ceramics are systematically studied. CaCl 2 -KCl serves as both a pore former and an additional source of CaO, eliminating the need for additional salt-washing treatment. By optimizing CaCl 2 -KCl content to 20 wt%, porous CA 6 ceramics with well cross-interlocking plate-like structures, possessing low thermal conductivity of 0.32 W·(m·K)−1 (1000°C), high apparent porosity of 68.28%, and desirable compressive strength of 6.76 MPa, are fabricated at 1300°C. This work not only validates the promising applicability of porous CA 6 materials for thermal insulation, but also introduces an auspicious fabrication methodology for thermal insulation materials. [ABSTRACT FROM AUTHOR]

The main objective of this study was to utilize coal gangue as the primary raw material and SiC as the foaming agent to successfully prepare foamed ceramics using the high-temperature foaming method. The study investigated the composition and crystal phases of the foamed ceramics formulation, the influence of sintering parameters on the microstructure and physical properties of the samples, as well as the reaction mechanisms during the foaming process. The experimental results showed that when the SiC addition amount was 2.5 wt%, the sintering temperature was 1230°C, and the sintering time was 60 min, the bulk density of the foamed ceramics reached as low as 0.414 g/cm3, with a compressive strength of 1.64 MPa and a closed porosity as high as 74.86%. Additionally, the water absorption and thermal conductivity were simultaneously reduced to 1.48% and 0.1968 W/(m·K), respectively. Besides maximizing the utilization of coal gangue, foamed ceramics also demonstrated excellent porous structure and physical properties, making them suitable for use as thermal insulation materials. [ABSTRACT FROM AUTHOR]

Advanced inorganic insulation materials with long term safety service performance at high temperature is crucial for energy saving of high-temperature equipment and steam transportation pipelines. We have developed a novel ceramic composite insulation material (CCIM) which has been proven to have excellent insulation capacity at high temperatures. This study investigated the high temperature stability of CCIM and its performance evolution. It was found that the thermal conductivity of the material decreased initially and then increased a little with the increase of heat treatment temperature. Overall, it maintained good insulation and mechanical properties below 600 °C. At a heat treatment temperature of 800 °C, the thermal conductivity of the material increased slowly with the increase of heat treatment time, but the compressive strength decreased rapidly. The accelerated aging experimental method was used to predict the performance changes of CCIM after long-term use, which shows the material can serve normally for 14.73 years at 600 °C. The excellent long term thermal stability can be verified by a real case of application in power plants for over ten years. The material's structure did not show significant change after ten years' service at 560 °C, therefore still maintained good thermal insulation capability. [ABSTRACT FROM AUTHOR]

There is still a lot of research space and market demand for lightweight, heat-insulating, and EMI-shielding construction materials. This paper develops and compares the thermal insulation, ohmic heating effect, and EMI shielding properties of a kind of multifunctional sandwich material with "ROTIS" and "FLAT" structures. The ROTIS-structured sample exhibits slightly higher thermal conductivity than the FLAT-structured sample, owing to its lower volume porosity and higher plated copper content per unit area. Since ROTIS technology allows for a significant increase in the thickness of thinner raw materials, this structure allows for an increase in the thermal insulation of thinner materials. Also, samples with ROTIS structures have a better ohmic heating effect than samples with FLAT structures. This is because the active layer has more plated copper content per unit area, while the insulation layer has less thermal resistance. Unsatisfactorily, the samples with the ROTIS structure show lower electromagnetic shielding effectiveness at 1-1.5 GHz, which is mainly due to their reduced volume porosity. In conclusion, this research develops sandwich materials with the ROTIS structure that exhibit excellent thermal insulation, electromagnetic shielding, and ohmic heating properties, making them suitable for use as building materials in demanding indoor temperatures and electromagnetic environments. [ABSTRACT FROM AUTHOR]

The current study used degree-day method to determine the optimum insulation thickness for different insulation materials. Some of the commonly used insulation materials available in the market are considered in the study. Materials used in the study are, fiberglass rigid, urethane rigid, fiberglass urethane, perlite, and extruded polystyrene. The cooling degree days were calculated using the base temperature varies from 18°C to 26°C for the four major cities like Mumbai, New Delhi, Kolkata, and Chennai of India. The study aims to analyze the effect of the number of cooling degree days and base temperature on insulation thickness and also determine the variation of annual cooling cost with the insulation thickness. The result shows that the optimum insulation thickness varies with the cooling degree days and is also influenced by the electricity rate and the cost of insulation material. Based on the result, it is found that optimum insulation thickness is affected by the thermal conductivity of the material, base temperature, CDD, material cost, and fuel cost. The result shows best suitable insulation materials for Delhi, Mumbai, Kolkata, and Chennai are urethane rigid, fiberglass urethane, urethane rigid, and fiberglass rigid respectively. The optimum insulation thicknesses vary between 1 and 12 cm for the different base temperatures and cities. Annual cooling cost per m2 is calculated for the base temperature 21 °C and 24 °C, and the result shows that fiberglass urethane has the lowest annual cooling cost for different cities. Energy-saving varies with the thickness of the insulating materials apply on the wall. In addition with the help of insulation, energy can be saved up to 80% and achieve energy-efficient buildings. [ABSTRACT FROM AUTHOR]

High-temperature insulation materials are used extensively in civil engineering as flame retardant materials, as well as in numerous industrial sectors. The raw materials used in the production of these materials include rocks and industrial waste. The article substantiates the feasibility of using ceramovermiculite and ceramoperlite materials containing a wollastonite binder as high-temperature insulation. The materials were obtained through the firing of a charge containing chalk, diatomite, and a heat-resistant filler (expanded perlite or expanded vermiculite). The material of the fired samples with expanded vermiculite is primarily composed of the crystalline phase of wollastonite and biotite, with a minor amount of quartz and akermanite-gehlenite. The use of expanded perlite as a heat-resistant filler results in the presence of a low amount of plagioclases in addition to the crystalline phase of wollastonite in fired samples, along with an amorphous phase. The physicomechanical properties of the charge and the fired samples were determined, and the effect of the apparent density and phase composition of the developed materials on the variation in their thermal insulation properties at high temperatures was studied. The thermal insulation properties of the materials were determined by supplying heat flow from the heating chamber of the muffle furnace to one side of the sample. The samples from the developed materials exhibited apparent densities ranging from 375 to 630 kg/m3 and compressive strengths between 0.95 and 3.25 MPa. The developed ceramoperlite materials containing wollastonite binder can be used as high-temperature thermal insulation up to +900°C, while ceramovermiculite can be used up to +1050°C. According to a range of physicomechanical and thermophysical properties, the materials obtained are comparable to or exceed the performance of known analogs. [ABSTRACT FROM AUTHOR]

Transformers are crucial equipment in electrical distribution systems but have a significant potential for failure. Insulation materials, including transformer oil (TO), play a primary role in transformer failures. A fire involving the TO can lead to a large explosion, causing the main tank to rupture and resulting in extensive damage to the entire transformer and the surrounding area. Mineral oil (MO) is the most widely used type due to its availability and relatively low cost compared to other types of oil. However, MO has a critical disadvantage, which is its very low flash point. The low flash point makes MO highly flammable. When the oil fires in an enclosed space, such as a transformer tank, the pressure inside the tank increases, leading to a large explosion. Therefore, research on increasing the flash point of MO is highly necessary. The application of nanotechnology is a promising approach to increasing the flash point of base fluids. Research on the effect of nanoparticles (NPs) on flash points is very limited in the literature; thus, there is significant potential for further research in this field. The majority of studies indicate an increase in flash points with the addition of NPs to MO. There is only one study that shows a decrease in flash point, which is −1.33% compared to MO. From all the reviewed studies, it can be concluded that NPs are a potential solution to increase the flash point of MO. Despite their benefits, NPs require a thorough examination of health and environmental impacts, along with proper waste management, to ensure their advantages. [ABSTRACT FROM AUTHOR]

With the increasing depletion of shallow resources, mining has gradually shifted to deeper levels, and the high-temperature problem of deep mining has restricted the efficient and safe development of mining. In this study, five types of thermal insulation materials for surrounding rocks with different ratios were produced using tailings, P.O.32.5 clinker, aluminum powder, glass beads, quick lime, and slaked lime as test materials. Based on the uniaxial compression test, the thermal constant analysis test, and numerical simulation analysis technology, the change rule of mortar compressive strength and thermal conductivity was analyzed, and the cooling effect of surrounding-rock thermal insulation materials with different ratios was discussed. The results showed that the compressive strength of the surrounding-rock thermal insulation materials ranged from 0.39 to 0.53 MPa, and the thermal conductivity ranged from 0.261 to 0.387 W/(K·m), with the compressive strength of ratio E being the largest and the thermal conductivity of ratio A being the lowest. In the numerical simulation analysis results, the thermal insulation layer thickness was taken as a value of 10 cm when, at this time, the best thermal insulation effect and economic benefits involved a temperature reduction of 0.9 K. In the case of changing the thermal conductivity and inlet wind speed, the original temperature of the rock temperature reduction was also very clear, with maximum reductions of 0.92 K, 0.92 K, and 1.42 K. [ABSTRACT FROM AUTHOR]

As the mining depth of major gold mines around the world increases, high-temperature surrounding rock transfers a significant amount of heat to the airflow in roadways, thereby significantly raising the air temperature. The use of insulating materials on roadway surfaces has proved to be an effective method for improving the thermal environment of underground workplaces. This study validates the functionality of pumping wet shotcrete with phase change materials (PWS-MPCM), previously developed for roadway support, using fluid dynamics numerical simulation to analyze the temperature distribution within the surrounding rock. The results show that PWS MPCM significantly impacts the temperature distribution within the surrounding rock and exhibits excellent thermal insulation and temperature control properties. This study demonstrates that PWS-MPCM can be a fundamental solution for mitigating heat hazards in deep gold mines. [ABSTRACT FROM AUTHOR]

The microstructure and chemical properties of the corona discharge process could provide an effective method for predicting the performance of high-voltage cable insulation materials. In this work, the depth profile of the microstructure and chemical characteristics of corona discharge-treated PE were extensively investigated using Doppler broadening of position annihilation spectroscopy accompanied with positron annihilation lifetime spectroscopy, attenuated total reflectance Fourier transform infrared spectra, Raman spectra and contact angle measurement. By increasing corona discharge duration, the oxygen-containing polar groups, including hydroxyl, carbonyl and ester groups, strongly contribute to the deterioration of hydrophobicity and the enhancement of hydrophilicity. And the mean free volume size, with a broadening distribution, decreases slightly. The line shape S parameter decreases because of the decrease in free volume elements and the appearance of oxygen-containing groups. Also, the thickness of the degradation layer, determined from the S parameter with positron injection depth, increases and diffuses into the PE matrix. A linear S-W plot within the degradation layer of different corona treatment duration samples indicates the defect type does not change. The S parameter decreases and the W parameter increases with an increasing corona duration. Using a slow positron beam, the nondestructive probe can be used to profile the microstructure and chemical environment across the corona discharge damage depth, which is beneficial for investigating the surface and interfacial insulation materials. [ABSTRACT FROM AUTHOR]

Accurately measuring water holdup in horizontal wells is crucial for effectively using heavy oil reservoirs. The capacitance method is among the most widely used and accurate techniques. However, the absence of suitable insulating materials at high temperatures and pressures limits the effectiveness of capacitive water holdup measurement in heavy oil thermal recovery. This study introduces a new composite material based on an aviation-grade, special glass glaze as the insulating medium doped with inorganic components (CaSO4, MgSO4, Ca(OH)2, and SiO2). This new composite material demonstrates outstanding insulating performance under high-temperature and high-pressure conditions in water. A water environment with a high temperature of 350 °C and a pressure of 12 MPa considerably enhances the composite material's insulation. After 72 h of continuous use, the insulation performance remains 0.3 MΩ. The layers exhibit improved insulation and stability, maintaining integrity through five consecutive temperature shocks in 500 °C air and 20 °C water. XRD, IR, SEM, and TEM analyses reveal that the new composite material is amorphous after firing and that the addition of inorganic components improves the bonding between the glass glaze components and contributes to a denser structure. Simultaneously, SEM and TEM analyses indicate that adding inorganic components results in a smoother, crack-free, and more compact surface of the special glass glaze. This enhancement is crucial for the material's long-term stability in high-temperature and high-pressure water environments. [ABSTRACT FROM AUTHOR]

To improve the magnetic properties of iron-based soft magnetic composites (SMCs), polytetrafluoroethylene (PTFE) with excellent heat resistance, electrical insulation, and extremely high electrical resistivity was chosen as an insulating coating material for the preparation of iron-based SMCs. The effects of PTFE content, compaction pressure, and annealing treatment on the magnetic properties of Fe/PTFE SMCs were investigated in detail. The results demonstrate that the PTFE insulating layer is successfully coated on the surface of iron powders, which effectively reduces the core loss, increases the resistivity, and improves the frequency stability and the quality factor. Under the combined effect of optimal PTFE content, compaction pressure, and annealing treatment, the iron-based SMCs exhibit a high effective permeability of 56, high saturation magnetization of 192.9 emu/g, and low total core losses of 355 mW/cm3 and 1705 mW/cm3 at 50 kHz for Bm = 50 mT and 100 mT. This work provides a novel insulating coating layer that optimizes magnetic properties and is advantageous for the development of iron-based SMCs. In addition, it also provides a comprehensive understanding of the relationship between process parameters and magnetic properties, which is of great guiding significance for scientific research and industrial production. [ABSTRACT FROM AUTHOR]

As one of the core components of electric vehicles, Li-ion batteries (LIBs) have attracted intensive attention due to their high energy density and good long-term cycling stability. However, some abuse conditions inevitably occur during battery operation, resulting in safety accidents such as the thermal runaway (TR) of LIBs. Therefore, the efficient and appropriate thermal insulation material design is crucial for LIB packs to effectively reduce or even inhibit the spread of TR. Based on it, in this review, we present the principle and influences of TR to provide the necessity of battery thermal management and thermal insulating materials. Then, we deeply discuss and compare the two kinds of representative thermal insulating materials: phase change thermal insulating materials and barrier-type thermal insulating materials. Their properties, synthesis methods, and modification means are investigated to provide some guidance for the future application of high-performance thermal insulating materials in the field of LIBs. [ABSTRACT FROM AUTHOR]

In recent years, electrical fires, which constitute the majority of fire incidents, have become a significant concern. This paper presents a quantitative evaluation of the research on electrical fires from 1993 to 2022, using literature measurement and visual analysis techniques. A total of 2915 publications were collected from the Web of Science database to review and analyze the research progress on electrical fires. In this investigation, the quantitative distribution of literature by year as well as the distributions of main source journals, countries and regions, institutions, and discipline categories were analyzed. Additionally, research hotspots were identified and the knowledge field was mapped using VOSviewer. The results indicated an exponential growth in the number of publications on electrical fires, with Ceramics International emerging as the most prolific journal, having published 79 papers and accounting for 2.5% of the total research. The most active countries in electrical fire research were found to be China, the United States, South Korea, India, Germany, France, and the United Kingdom, with Chinese publications having the most significant impact. The University of Science and Technology of China, Chinese Academy of Sciences, and Tsinghua University are the most productive institutions in the field of electrical fire research; their main research directions include electrical structure, electrical experiment simulation, insulating materials, battery fires, fire extinguishing technology, and detection methods. Further, we observed that the scope of research on electrical fires has expanded from the macro to micro level. Thematic analysis conducted in the last decade has revealed that battery fires and equipment materials have emerged as the primary focus of research in this field. These research findings offer a comprehensive overview of the evolution of research hotspots, which can assist researchers in quickly grasping the research frontiers as well as the overall situation. [ABSTRACT FROM AUTHOR]

Examining the thermodynamics of phase change materials (PCMs) when merged into construction materials is a significant subject within the realm of building science and environmental responsibility. When infused to construction materials like bricks, PCMs have the capacity to elevate a building's temperature regulation by minimizing the energy required for thermal contentment. This research is dedicated to learn about the thermal conduct and the consequences of the fusion of calcium chloride hexahydrate mineral (CCHPCM) within the pores of a masonry unit. To achieve this, we implemented a practical testing specifically designed to scrutinize how CCHPCMs alter the thermal performance of studied compounds. Multiple configurations were designed by adjusting the arrangement of CCHPCM within the bricks, resulting in three distinct setups. The first set involved filling one row of the bricks, the second set entailed filling two rows, and the final configuration entailed filling all the pores with PCM. Additionally, a computational modeling was executed to survey the thermic behavior of bricks infused with CCHPCM, operating with COMSOL Multiphysics application program. The elaborated work concluded to having an enhancement of the brick's thermal storage capacity, for Set-3, in which all rows of bricks are filled with PCM, a delay of 2 h is observed compared to Set-0 the brick without CCHPCM. This simulation also encompassed comparative findings regarding the thermal performance of CCHPCM when incorporated into the masonry unit. Overall, this study supplied the valorization of CCHPCMs infused in masonry units and their usage in distinct layouts on upgrading its candidature to achieving environmental responsibility. [ABSTRACT FROM AUTHOR]

The present project investigated the hygrothermal performance and risk of mould growth in solid masonry walls retrofitted internally with three diffusion-open bio-based insulation materials (two loose-fill cellulose and one hemp fibre), installed in test containers with controlled indoor climate. Focus was on bio-based insulation materials, as these are upcoming due to necessary CO2 reductions and because the hygroscopic properties of bio-based materials are different from traditional insulation materials like mineral wool therefore, some manufacturers claim a vapour barrier is unnecessary, even in relatively cold climates. The project was a large experimental study in two reefer containers with reconfigured facades, in which solid masonry walls with embedded wooden elements were constructed. The study focused on the conditions in the masonry/insulation interface and in the embedded wooden elements. The effect of hydrophobization and different indoor moisture loads were also investigated. Moreover, the bio-based insulation systems were compared with a wall insulated with the traditional mineral wool and vapour barrier system. Relative humidity and temperature were measured at several locations in the test walls for 1 year and 9 months. Measurements show that exposed masonry walls retrofitted internally with diffusion-open bio-based insulation materials resulted in unacceptably high moisture levels (>80% RH over longer periods). Lower moisture levels were observed when the internal insulation was combined with hydrophobization against wind-driven rain, but unacceptably high moisture levels still occurred (60%–70% in summer and 95%–100% in winter in the interface). Hydrophobization reduced the moisture levels in the interface and embedded wooden elements only in walls facing southwest, which is the direction with the most wind-driven rain. Mould growth tests showed no growth in the interface in walls insulated with cellulose insulation (mycometer surface value <25). Meanwhile growth was found in all four walls insulated with hemp fibre matts (mycometer surface value >400). [ABSTRACT FROM AUTHOR]

Maintaining high surface area and porosity at high temperatures is important when considering aerogels for use in thermal management systems. The mesoporous structure of aerogels results in extremely low thermal conductivity, making them lightweight, high performance insulating materials. Maintaining these properties requires innovative routes to suppress sintering and pore collapse as use temperatures rise. The current work aims to improve the pore structure stability of yttria‐stabilized zirconia aerogels by the addition of a SiO2 coating. The functionalization of surface hydroxyl groups by the addition of SiO2 is hypothesized to mitigate condensation reactions, which are a driving force for shrinkage and pore structure collapse. Zirconia aerogels with 0, 10, and 30 mol% yttria (YO1.5) additions were coated in a tetraethyl orthosilicate (TEOS) solution and exposed to temperatures up to 1200°C. Crystal structure, pore structure, and aerogel morphology were investigated to understand changes in aerogel thermal stability. The SiO2 coating exhibited a greater influence on pore stability over yttria concentration, with specific surface area of the coated aerogels being twice that of the uncoated aerogels up to 1000°C. However, the presence of the SiO2 coating promoted rapid sintering and densification at 1200°C, establishing an upper use temperature for SiO2 and a need to develop other coating chemistries. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to utilize two types of gypsum mold wastes from two different factories as novel and economical reinforcing fillers for composites that may be useful for building materials and floors. Two types of gypsum mold wastes from two different factories as raw materials were incorporated into linear low density polyethylene (LLDPE) aiming to get rid of that waste in one hand and obtaining useful economical composites suitable for building materials and floors. Design/methodology/approach: Composites were prepared from two types of gypsum mold wastes substituted with different ratios from raw gypsum and LLDPE throughout the melt blending technique. The physico-mechanical and electrical investigations in addition to the morphology of the composites were included. Findings: The mechanical results illustrate that substituting commercial gypsum with gypsum mold waste positively affects tensile strength, flexural strength and hardness shore D for the LLDPE composites. The tensile strength increased from 5 MPa for LLDPE filled with commercial gypsum as blank samples to 11.2 and 13.2 MPa for LLDPE filled with D and S waste. Also, electrical properties which include both permittivity ɛ′ and dielectric loss ɛ″ increased with increasing the waste content in the LLDPE matrix. In addition to the electrical conductivity values, σ lies in the order of insulation materials. Consequently, it is possible to produce materials with a gypsum matrix by adding industrial waste, improving the behavior of the traditional gypsum and enabling those composites to be applied in various construction applications as eco-friendly tiles. Originality/value: This study aims to prepare eco-friendly composites based on LLDPE and waste gypsum mold to preserve resources for the coming generations, other than lowering the environmental footprint and saving the costs of getting rid of it. [ABSTRACT FROM AUTHOR]

Addressing the challenge of existing insulation materials struggling to achieve the synergy of lightweight construction, high strength, and low thermal conductivity, this paper presents a method based on multi-material assembly technology to achieve a controlled composite of a three-dimensional continuous silicon carbide network and graphite matrix. Following an examination of the impact of various forming densities and the addition of expandable graphite on the thermal conductivity and compressive strength of graphite/SiC composites, the study explored the effects of different "enhancement network" topologies on the properties of these composites. The investigation demonstrates that adjusting the forming density and incorporating expandable graphite enable regulation of both the porosity and closed porosity of the composites, thereby controlling their compressive strength and thermal conductivity. Additionally, the construction of a three-dimensional continuous SiC network structure within the graphite matrix significantly enhances the compressive strength of the composites, with only a slight increase in thermal conductivity. A graphite/SiC composite thermal insulation material was ultimately developed, boasting a density of merely 1.1 g/cm³, a low thermal conductivity of 1.847 W/m·K, and an impressive compressive strength reaching 15.627 MPa. Its overall performance surpasses that of water-glass sand, making it a promising candidate for various applications in the foundry industry as a thermal insulation material. [ABSTRACT FROM AUTHOR]

In this study, PMMA/SiO2 composites were fabricated with monodispersed SiO2 and PMMA using four distinct methods—physical blending, in situ polymerization, random copolymerization, and block copolymerization—to investigate the composites' thermal, mechanical, and optical properties. In the physical blending approach, SiO2 nanoparticles were dispersed in a PMMA solution, while during in situ polymerization, silica nanoparticles were incorporated during the synthesis of PMMA/SiO2 composites. 3-methacryloxypropyltrimethoxysilane (MPS) was modified on the SiO2 surface to introduce the reactive double bonds. The MPS@SiO2 was either random- or block-copolymerized with PMMA through RAFT polymerization. The PMMA/SiO2 composites prepared via these different methods were characterized using FTIR, TGA, and DSC to determine their chemical structures, thermal degradation temperatures, and glass transition temperatures, respectively. Scanning electron microscopy (SEM) was employed to observe the microstructures and dispersion of the composites. This comprehensive analysis revealed that the PMMA/SiO2 composites prepared via block copolymerization exhibited thermal stability at temperatures between 200 and 300 °C. Additionally, they demonstrated excellent transparency (86%) and scratch resistance (≥6H) while maintaining mechanical strength, suggesting their potential application in thermal insulation materials. [ABSTRACT FROM AUTHOR]

Metallum Fire-Resistant paint, denoted as MFR henceforth, represents a cutting-edge insulating material with dual functionality as a fireproof solution, presenting substantial advantages in the realm of construction applications. This exposition derives its primary insights from the scholarly contributions documented in publications. The focal point of these investigations includes the assessment of fire hazards associated with polyethylene materials in building structures and the enhancement of mortars in high-temperature environments in tunnels. The purpose of this study is to evaluate the effectiveness of a modified cork-based coating (MFR) compared to traditional coatings in terms of corrosion protection, fire resistance, and thermal insulation properties in construction applications. This evaluation focuses on quantifying the efficacy of MFR by examining key properties, such as adhesion, the reduced thickness required for fire protection, thermal conductivity reduction, and corrosion resistance under extreme environmental conditions. MFR is highly effective in fire prevention for buildings and tunnels, withstanding temperatures over 1000 °C while maintaining structural integrity. A unique aspect of MFR is its use of cork shavings, a typically underutilized byproduct from wine-bottle-stopper production. This innovative not only amplifies MFR's fire-resistant attributes, but also introduces sustainability and judicious resource utilization into its manufacturing processes. [ABSTRACT FROM AUTHOR]

Thermal insulation applications on the exterior facades of buildings have been the subject of numerous studies from the past to the present. Some of these studies focus on the cost reduction effect of insulation, while others emphasize its ecological benefits. In this study, multi-objective optimization, the objectives of which are minimum cost and minimum CO2 emission, has been carried out with the NSGA-II method. In emission calculations, in addition to fuel-related emissions, the carbon footprint of all materials comprising the wall has also been included. The multi-objective optimization study examined four design variables: wall thickness, wall material (light concrete, reinforced concrete, and brick), insulation material (expanded polystyrene, extruded polystyrene, mineral wool, and polyurethane foam), and heating source (natural gas, electricity, fuel oil). Analyses have been carried out for four cities (Osmaniye, Bursa, Isparta, and Erzurum), which are located in different climatic regions, and considering solar radiation effects. An existing building has been taken as the base case scenario, and the study has determined the improvements in the total cost and the amount of CO2 released into the environment when the appropriate insulation material, insulation thickness, wall material, and heating source identified in the multi-objective optimization study have been used. At the cost-oriented optimum point in the study, the most suitable insulation material was found to be expanded polystyrene, the most suitable wall material was brick, and the most suitable heating source was natural gas. In the CO2-oriented optimum, in contrast to the cost-oriented approach, optimal results have been obtained when light concrete was selected as the wall material. [ABSTRACT FROM AUTHOR]

The recycling of materials is in line with the policy of a closed-loop economy and is currently an option for managing waste in order to reuse it to create new products. To this end, 3D printing is being used to produce materials not only from pure polymers but also from their composites. Further development in this field seems interesting and necessary, and the use of recycled materials will help to reduce waste and energy consumption. This article deals with the use of degradable waste materials for the production of insulating materials by 3D printing. For the study, samples with different numbers of layers (one and five), composite thickness (20, 40, 60, 80, and 100 mm) and composition (including colored resins that were transparent, black, gray, and metallized, as well as resins that were colored gray using soybean oil and gray using natural fibers) were made. The role of natural fillers was played by glycerin and biomass ash with a weight ratio of 5%. The finished materials were tested, and the values of the coefficient of thermal resistance and heat transfer were determined. The best thermal properties among the tested materials were distinguished by a five-layer sample made of soybean-oil-based resin with a thickness of 100 mm. This sample's heat transfer coefficient was: 0.16 W/m2K. As a material for thermal insulation in 3D printing technology, biodegradable components have great potential. [ABSTRACT FROM AUTHOR]

Silica aerogels (SA) have exceptional thermal insulation capabilities, however, their superhydrophobic nature hinders the formation of a uniform composite when combined with cement slurry. To address this issue, an aqueous solution was employed to disperse SA particles using sodium dodecyl sulfate (SDS). Subsequently, the dispersed micelles were coated with polydopamine (PDA) through in situ polymerization. This approach effectively enhanced the dispersion of SA in cement slurry and improved its connection force with the cement hydration products, thereby mitigating the adverse effects of aggregated SA on the mechanical properties of the cement composite. The successful PDA coating led to the formation of smaller aggregated micelles, resulting in a 30% improvement in compressive strength of cement composites containing modified SA compared to those using unmodified SA, while maintaining the desired thermal conductivity properties. With a strategic increase in the quantity of modified SA, a remarkable thermal conductivity of 0.1351 W/m·K was achieved without significantly compromising the compressive strength, which reached about 13.94 MPa. This enhanced compressive strength surpassed that of conventional thermal insulation materials like expanded polystyrene (EPS) and foam concrete. Consequently, this novel technique has the potential to markedly enhance the thermal insulation of cement composites without excessively impacting their compressive strength, thus contributing to the development of green insulation and energy-saving building materials. [ABSTRACT FROM AUTHOR]