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The purpose of this paper is to examine the thermal insulation and water vapor transmission rate (WVTR) according to the type of the filling material, and compared the thermal insulation in the dynamic state considering actual wearing conditions.

The thermal insulation and WVTR were evaluated in a standard state depending on the type of filling material (goose down (GD), duck down (DD), Thinsulate700 (T700), Thinsulate600 (T600) and Polyester (PET)), and the changes in thermal insulation were examined by measuring the microclimate in the case of an environmental change from a high temperature to a low temperature. In addition, the clumping of filling material and the changes in the thickness/weight depending on the laundry process were observed, and the relationships with the thermal insulation were analyzed.

The results showed that for natural filling materials (GD and DD), the thermal insulation deteriorated significantly due to changes in the thickness/weight after laundering ten times, and water washing was more appropriate than the dry cleaning. On the other hand, the artificial filling materials (T700, T600 and PET) showed a relatively smaller difference, except for clumping, when they went through more dry cleaning or water washing cycles compared to the natural filling materials.

The results showed that the laundry methods have different effects on the damage to the filling material, the change in thermal insulation, and the change in the comfort-related physical property. Therefore, it is important to select the optimal laundry method depending on the filling material.

Nowadays, thermal comfort plays a prominent role in contemporary construction practices. Appropriate thermal insulation not only offers energy efficiency benefits in buildings but also enhances occupant well-being, comfort, and productivity. Therefore, a comprehensive understanding of the thermal properties of building materials is essential. This research aims to prepare and investigate a lightweight gypsum-based composite incorporating nano montmorillonite with advanced thermal insulation properties, considering both quality and cost-effectiveness while ensuring environmental compatibility.

This study adopts a laboratory experimental approach. A gypsum sample (without additives) and seven samples of gypsum combined with varying percentages of sodium and calcium montmorillonite nanoclays undergo extensive testing and analysis. Subsequently, the properties of these samples are compared.

The results indicate that adding montmorillonite nanoclays to gypsum composites reduces the density of the tested samples and increases their porosity. Moreover, the thermal conductivity coefficient decreases in these samples, significantly improving the thermal insulation properties of the lightweight gypsum plaster. This improvement is more pronounced in samples containing sodium montmorillonite nanoclay compared to calcium-based samples. Additionally, the investigations reveal that compressive strength decreases with the addition of montmorillonite to the samples.

In this research, laboratory experiments were conducted to investigate the physical and mechanical properties of gypsum plaster with varying percentages of sodium and calcium montmorillonite nanoclays. The studied properties include density, porosity, thermal conductivity coefficient, and compressive strength. Additionally, stress-strain diagrams, elastic modulus, and initial and secondary critical stresses were analyzed for each specimen.

Common Aero Vehicles (CAVs) are relatively small‐size, un‐powered, self‐maneuvering vehicles equipped with a variety of weapons and launched from space. One of the major obstacles hampering a full the realization of the CAV concept is a present lack of lightweight, high‐temperature insulation materials which can be used for construction of the CAV’s thermal protection system (TPS). A computational analysis is utilized in the present work to examine the suitability of a carbon‐based, coal‐derived foam for the TPS applications in the CAVs. Toward that end, a model is developed for the high‐temperature effective thermal conductivity of foam‐like materials. In addition, an insulation sizing procedure is devised to determine the minimum insulation thickness needed for thermal protection of the vehicle structure at different sections of a CAV. It is found that the carbon‐based foam material in question can be considered as a suitable TPS insulation material at the leeward side and at selected portions of the windward side of a CAV (specifically the portions which are further away from the vehicle nose).

The purpose of this paper is to deal with performance verification of thermal insulation fillings that are used for outer clothes into cold environments. Thermal properties of filling materials (down and three sophisticated fillings) were tested under condition approaching real weather conditions in Middle Europe.

In the paper, modern method of thermal resistance Rct measurement, by Sweating Guarded-Hotplate system, was compared with method of Technical University of Liberec (TUL method). The TUL method shows good results and it is applicable even at ambient temperatures below zero, which fully corresponds to real application of the insulation filling.

Evaluation of fibre battings were carried out even at temperatures below the freezing point, which is important for simulation of actual application of these filling structures. The highest thermal resistance of goose down confirm that natural materials have their irreplaceable position, especially in application into clothes for extreme conditions.

There does not include effect of the humidity change on thermal insulation properties. It will be subject of further research of authors.

The investigation of thermal insulation properties were carried out under conditions approaching real application of tested materials, namely, at low ambient temperature.

Thermal insulation is important to achieve energy efficiency in a buildings’ lifespan while maintaining comfort. Traditionally, the majority of insulation in buildings is man-made petroleum based products with limited or no-end life usage. However, from an environmental and economic sustainability perspective, they are not sustainable as natural resources are finite and in danger of run-out. Furthermore, they are also highly influenced by the increasing price and the ongoing scarcity of fossil fuel oils. The paper aims to discuss these issues.

This paper introduces soap based insulation from recycled materials as a sustainable alternative to petroleum counterparts. The methodology is lab based experimentation and iterative tests. The phased based research process for the incremental development of the soap based thermal insulation is explained.

Findings reveal that soap based insulation can be one possible way forward in the quest for natural and sustainable thermal insulation from recycled products to preserve and conserve the sustainable environment.

Thus, the paper provides a unique environmentally friendly approach as an alternative to those existing petroleum counterparts for thermal insulation in buildings.

In this paper, a method of designing flexible multilayer insulation is analyzed and discussed, with focus on reducing the three basic modes of heat transfer (thermal radiation, solid spacer and residual gas conduction). The foundation for designing the new flexible thermal insulation material is provided. The insulation performances of different types (by choosing different reflection shields and spacers) of flexible multilayer insulation materials are obtained through measurements using a KES-F7 Thermal Labo II apparatus. The thermal performance of flexible multilayer insulation materials at different layers are also presented, and the best is about 20∼25 layers. To improve the thermal performance of multilayer insulation materials, treble spacers between double aluminized shields are applied. Aluminized shields with air, meshes, wool fibres, etc. are compared with each other. The aluminized shields with meshes fixed with down can reduce thermal contact, which reduces the radiation heat transfer more fully and can be more steady than the other spacers in the project applications. With the same layers and spacers, the thermal conductivity of crinkled aluminized shields is lower than that of the smooth aluminized shields. The effects of compressive loads on layer density and thermal performance are also investigated.

Determining the suitable material and accurate thickness of the thermal insulation layer used in exterior walls during the design phase of a building can be challenging. This study aims to determine suitable material and optimum thickness for the insulation layer considering both operational and embodied factors by a comprehensive assessment of the energy, economic and environmental (3E) parameters.

First, the energy model of an existing building was created by using Autodesk Revit software according to the as-built floor layout to evaluate the impact of five alternative insulating materials in varying thickness values. Second, using the results derived from the model, a thorough evaluation was conducted to ascertain the optimal insulation material and thickness through individual analysis of 3E factors, followed by a comprehensive analysis considering the three aforementioned factors simultaneously.

The findings indicated that polyurethane with 13 cm thickness, rockwool with 10 cm thickness and EPS with 20 cm thickness were the best states based on energy consumption, cost and environmental footprint, respectively. After completing the 3E investigation, the 15-cm-thick mineral wool insulation was presented as the ideal state.

This study explores how suitable material and thickness of insulating material can be determined in advance during the design phase of a building, which is a lot more accurate and cost-effective than applying insulating materials by assumed thickness in the construction phase.

To the best of the authors’ knowledge, this paper is unique in investigating the advantages of using thermally insulating materials in the context of a mosque structure, taking into account its distinctive attributes that deviate from those of typical buildings. Furthermore, there has been no prior analysis of the cost and sustainability implications of these materials concerning the characteristics of subtropical monsoon climate.

In the present work, the thermal insulation characteristics of multilayered mittens were studied in different airflow conditions.

In this study, the thermal behavior of four groups of mittens consisting of one two-layer and three three-layer mittens containing nonwoven wadding materials with various weights and thicknesses was investigated during the exposure to airflows with different speeds. In order to evaluate the correlation between the heat transfer rates of different mittens with the human perception of cold, a set of pair-comparison tests was performed using Thurstone's law of comparative judgment.

The analysis of the results revealed that by an increment in the weight and the thickness of the wadding material, the thermal protection performance of mittens improves. Moreover, in the presence of airflow and by increasing its speed, due to the forced convective heat loss, the outer surface temperature of the mittens decreases and therefore the conductive heat transfer rate rises. This fact leads to the transfer of higher quantity of body warmth to the environment and thus feeling of coldness. According to the results, there was a proper correlation between the subjective perception of cold and the heat transfer rate of mittens. The statistical analysis of the results clarified that the effect of mitten's structural parameters and the airflow speed on the thermal protection behavior of mittens are significant at the confidence range of 95%.

Mitten is one of the important personal protective clothing, especially in cold environments. Thus, the thermal resistance of them has a prominent role in the protection of the hands and fingers from cold and frostbiting.

Empire style fashion, Greek-Roman style robe with bare shoulder and chest and short sleeved with long gloves which created a slim silhouette, was worn even in winter season in Europe, where average temperature is 0-5°C. Most women suffered with catching cold and thousands caught flu and tuberculosis of the lungs, called muslin disease. The purpose of this paper is to find out clothing insulation of the robe by measuring the thermal resistance and to guess how cold they felt in this robe in winter time.

The authors performed the investigation on original robe shape with based on historical evidence and data, such as drawings, sketches, pattern books and sewing books, and reproduced a representative robe costume and tested its thermal insulation. The fabrics of robe were thin wool, silk and cotton following the literature evidence and preserved costume. Thermal insulation of the robes was measured using thermal manikin with the test method ISO 15831. The authors analyzed the thermal insulation of reconstructed robes with an inner cotton breech as for daily use and tested them wrapped with cashmere shawl on manikin shoulder as for severe cold weather.

The dress robes had the range of 0.61-0.67 clo regardless of the type of fabric materials, and 0.80-0.81 clo with the cashmere shawl. These values were not enough for women to keep body temperature or comfort in winter time.

This study combined fashion historic theory for costume reproduction with clothing science and technology for thermal insulation. Combination of costume history, construction technology and measurement engineering is the ingenious idea, and the combination of historical and scientific research evidences interdisciplinary originality.

The purpose of this study is to improve the mechanical properties, thermal insulation properties and flame retardant properties of polyethylene terephthalate (PET), the organic montmorillonite (OMMT)/SiO₂ aerogel/PET composites and fibers were prepared, and the effects of the OMMT/SiO₂ aerogel on the structure, thermal conductivity and flame retardance of the OMMT/SiO₂ aerogel/PET composites and their fibers were systematically investigated.

The OMMT/SiO₂ aerogel/PET composites and fibers were prepared by in-situ polymerization and melt spinning using SiO₂ aerogel as thermal insulation filler and OMMT (DK2) as comodified filler.

The experimental results showed that OMMT improved the crystallization properties of PET. Compared with the crystallinity of SiO₂ aerogel/PET composites (34.8%), SiO₂ aerogel/PET composites and their fibers reached 45.1% and 49.2%, respectively. The breaking strength of the OMMT/SiO₂ aerogel/PET composite fibers were gradually increased with the OMMT content. When the content of OMMT was 0.8 wt.%, the fracture strength of the composite fibers reached 4.40 cN/dtex, which was 54% higher than that of the SiO₂ aerogel/PET fiber. In addition, the thermal insulation properties of the composites and their fibers were improved by addition of fillers, and at the same time reached the flame retardant level. The thermal conductivity of the 0.8 wt.% OMMT/SiO₂ aerogel/PET composites was 101.78 mW/(m·K), which was 49.3% and 58.8% lower than that of the SiO₂ aerogel/PET composites and the pure PET, respectively. The thermal conductivity of the fiber fabrics woven from the 0.8 wt.% OMMT/SiO₂ aerogel/PET composites was 28.18 mW/(m·K), which was 29.0% and 44.6% lower than that of the SiO₂ aerogel/PET composite fiber fabrics and PET fiber fabrics. The flame retardancy of the composites was improved, with an limiting oxygen index value of 29.2% for the 0.8 wt.% OMMT/SiO₂ aerogel/PET composites, which was 4.1% higher compared to the SiO₂ aerogel/PET composites, and achieved the flame retardant level.

The SiO₂ aerogel/PET composites and their fibers have good mechanical properties, flame retardant properties and thermal insulation properties, exhibited good potential for application in the field of thermal insulation, such as warm clothing. Nowadays, as the energy crisis is becoming more and more serious, it is very important to improve the thermal insulation properties of PET to reduce energy losses and mitigate the energy crisis.

In this study, PET based composites and their fibers with excellent mechanical properties, thermal insulation properties and flame retardant property were obtained by using three-dimensional network porous silica aerogel with low density and low thermal conductivity as the thermal insulation functional filler and two-dimensional layered OMMT as the synergetic modified filler.