Development of Airlaid Non-Woven Panels for Building’s Thermal Insulation

2022 ◽  
Author(s):  
Melek Ayadi ◽  
Riadh Zouari ◽  
César Ségovia ◽  
Ayda Baffoun ◽  
Slah Msahli ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Thermal Insulation ◽  
New Technologies ◽  
Natural Fibers ◽  
Posidonia Oceanica ◽  
Woven Fabrics ◽  
Insulation Materials ◽  
Textile Technology ◽  
Woven Structures ◽  
Fabric Surface

As the need to ensure thermal comfort in buildings is constantly evolving, new technologies continue to emerge with the aim to develop efficient thermal insulation materials. This study aims to explore a textile technology using Airlaid process to develop non-woven fabrics made of natural fibers extracted from Posidonia Oceanica’s waste for assessing their suitability for insulation products in construction field. This technology offers the feature to develop isotropic non-woven structures by orienting randomly the fibers on the fabric surface. The web composed of a mixture of Posidonia Oceanica fibers and a proportion of thermoplastic fibers is then thermally bonded in an oven followed by cooling in order to ensure the solidification of the bonding areas. The prepared panels are then analyzed for the thermal conductivity. It was found that their thermal conductivity is close to commonly used thermal insulation materials, ranging between 0.03515 W/m.K and 0.03957 W/m.K, which allows the non-woven panels to compete with widely-used insulation materials for building’s field. The second part of this work aims to determinate the Posidonia panel's resistance to five common mold types in buildings (Aspergillus niger, Penicilumfuniculosum, Trichoderma viride, Chaetomium globosum, Paecilomycesvariotii). In fact, at high moisture content, molds are likely to develop on cellulosic materials affecting indoor air quality and eventually causing a variety of health risks to occupants. However, optic microscope results showed no growth of molds on the Posidonia samples which allows conceiving reliable thermal insulation materials.

Possibilities of Using Natural Fibres for Production of Particular Insulation for Use in Civil Engineering

2015 ◽  
Vol 1124 ◽  
pp. 111-116
Author(s):  
Martina Reif ◽  
Jitka Peterková ◽  
Jiri Zach
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Thermal Insulation ◽  
Civil Engineering ◽  
Research Work ◽  
Natural Fibers ◽  
Cellulose Fibers ◽  
Natural Fibres ◽  
Insulation Materials ◽  
Bast Fibers

The paper deals with the development options of particular insulation based on a blend of recycled cellulose fibers and natural (mainly) bast fibers. The paper presents the results of research work in the field of addiction thermal insulation, acoustic and mechanical properties of experimentally produced insulators on density..Keywords: Natural fibers, thermal conductivity, insulation materials, straw, fibreboard, cellulose fibers

Comparison of Thermal Insulation Concrete Panel Yield Based on Natural Fibres: A Review

2021 ◽  
Vol 02 (01) ◽  
Author(s):  
Norsyaza Aqilah Rosli ◽  
◽  
Mohd Fahmi Abdul Rahman ◽  
Keyword(s):  
Thermal Conductivity ◽  
Thermal Insulation ◽  
Date Palm ◽  
Natural Fibers ◽  
Microsoft Excel ◽  
Hemp Fiber ◽  
Insulation Materials ◽  
Concrete Panels ◽  
Coefficient Of Thermal Conductivity ◽  
Research Studies

Over time, many researchers have conducted studies to investigate the construction sector by assessing those related to energy, environmental and economic problems to find ways to improve global sustainability. The studies on the use of natural fibers: wheat, date palm and hemp as an insulating material in concrete panel yields have been conducted through ten previous research studies. In the market, there are various types of thermal insulation materials but these materials are sold at high prices and even worse some of them contain harmful chemicals that can threaten the health of consumers. This study is intended to identify ten previous research studies on the use of natural fibers in concrete panel yield as thermal insulation materials. Also, to analyse the data of density and coefficient of thermal conductivity accumulated through Microsoft Excel and propose the best concrete panels yield between these three types of natural fibers. The research was based on the value of density and coefficient of thermal conductivity of concrete panel yield. The results reveal that the presence of natural fibers in concrete panels can insulate heat well. The lowest thermal conductivity coefficient obtained from concrete of Hemp Fibre Gypsum (HG) with 0.051 W/mK. The composition of 35g of hemp fiber, 200g of gypsum and 130ml of water has shown that the amount of fibre and binder used plays an important role in determining the value of density and thermal conductivity. Finally, based on the analysis that has been conducted, found that density and thermal conductivity are inversely proportional when there is a change in the composition of fibers and binders in the concrete panel yields.

Development and Research of Thermal Insulation Materials from Natural Fibres

2014 ◽  
Vol 604 ◽  
pp. 285-288 ◽  
Author(s):  
Saulius Vaitkus ◽  
Rūta Karpavičiūtė ◽  
Sigitas Vėjelis ◽  
Lina Lekūnaitė
Keyword(s):  
Thermal Conductivity ◽  
Thermal Insulation ◽  
Preparation Method ◽  
Raw Materials ◽  
Natural Fibres ◽  
Current Work ◽  
Insulation Materials ◽  
Flax Fibres ◽  
Hemp Fibres

Natural fibres from flax and hemp are used as raw materials for efficient thermal insulation. In current work, tests were carried out using chopped and combed long flax fibres as well as chopped and combed long hemp fibres. Investigations have shown that thermal conductivity of natural fibres depends on their preparation method (combing, chopping) and materials density.

scholarly journals Rigid Polyurethane Foams Modified with Biochar

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5616
Author(s):  
Katarzyna Uram ◽  
Maria Kurańska ◽  
Jacek Andrzejewski ◽  
Aleksander Prociak
Keyword(s):  
Thermal Conductivity ◽  
Thermal Stability ◽  
Thermal Insulation ◽  
Foam Cells ◽  
Polyurethane Foams ◽  
Cross Sectional ◽  
Rigid Polyurethane Foams ◽  
Insulation Materials

This paper presents results of research on the preparation of biochar-modified rigid polyurethane foams that could be successfully used as thermal insulation materials. The biochar was introduced into polyurethane systems in an amount of up to 20 wt.%. As a result, foam cells became elongated in the direction of foam growth and their cross-sectional areas decreased. The filler-containing systems exhibited a reduction in their apparent densities of up to 20% compared to the unfilled system while maintaining a thermal conductivity of 25 mW/m·K. Biochar in rigid polyurethane foams improved their dimensional and thermal stability.

Glass-Oxide Nanocomposites as Effective Thermal Insulation Materials

2013 ◽  
Vol 1558 ◽  
Author(s):  
Qing Hao ◽  
Minqing Li ◽  
Garrett Joseph Coleman ◽  
Qiang Li ◽  
Pierre Lucas
Keyword(s):  
Thermal Conductivity ◽  
Thermal Insulation ◽  
Room Temperature ◽  
Phonon Scattering ◽  
Material Composition ◽  
Insulation Materials ◽  
Atomic Structures ◽  
Porous Nanocomposites ◽  
Theoretical Minimum

ABSTRACTWith extremely disordered atomic structures, a glass possesses a thermal conductivity k that approaches the theoretical minimum of its composition, known as the Einstein’s limit.1 Depending on the material composition and the extent of disorder, the thermal conductivity of some glasses can be down to 0.1-0.3 W/m∙K at room temperature,2,3 representing some of the lowest k values among existing solids. Such a low k can be further reduced by the interfacial phonon scattering within a nanocomposite that can be used for thermal insulation applications. In this work, nanocomposites hot pressed from the mixture of glass nanopowder (GeSe4 or Ge20Te70Se10) and commercial SiO2 nanoparticles, or pure glass nanopowder, are investigated for the potential k reduction. It is found that adding SiO2 nanoparticles will instead increase k if the measured k values for usually porous nanocomposites are converted into those for the corresponding solid (kSolid) with Eucken’s formula. In contrast, pure glass nano-samples always show kSolid data significantly reduced from that for the starting glass. For a pure GeSe4 nano-sample, kSolid would beat the Einstein’s limit for its composition.

Effects of boric acid addition and sintering temperature on the thermal conductivity of perlitebased insulation materials

2020 ◽  
Vol 62 (4) ◽  
pp. 408-412
Author(s):  
Yuksel Palaci
Keyword(s):  
Thermal Conductivity ◽  
Physical Properties ◽  
Boric Acid ◽  
Thermal Insulation ◽  
Sintering Temperature ◽  
Direct Relation ◽  
Insulation Materials ◽  
Acid Addition ◽  
Composition Characteristics

Abstract In this study, the variation of thermal conductivity and density of 15 wt.-% boric acid - 85 wt.-% sepiolite, 30 wt.-% boric acid - 30 wt.-% sepiolite - 40 wt.-% perlite, 30 wt.-% boric acid - 30 wt.-% cordierite - 40 wt.-% perlite and 30 wt.-% boric acid - 30 wt.-% alumina - 40 wt.-% perlite compositions at 700 °C and 900 °C sintering temperatures were investigated. The results show that increasing the amount of boric acid and decreasing the sintering temperature lead to an improvement in thermal insulation properties. There is a direct relation between the thermal conductivity and density of the specimens. Both physical properties change with a change in the sintering temperature and the composition characteristics. Minimum thermal conductivity has been observed in a specimen consisting of 30 wt.-% boric acid - 30 wt.-% alumina - 40 wt.-% perlite.

scholarly journals Technical Performance Overview of Bio-Based Insulation Materials Compared to Expanded Polystyrene

Buildings ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 81
Author(s):  
Cassandra Lafond ◽  
Pierre Blanchet
Keyword(s):  
Thermal Conductivity ◽  
Energy Efficiency ◽  
Natural Fibers ◽  
Expanded Polystyrene ◽  
Embodied Energy ◽  
Lower Amount ◽  
Vapor Permeability ◽  
Insulation Material ◽  
Insulation Materials ◽  
Technical Performance

The energy efficiency of buildings is well documented. However, to improve standards of energy efficiency, the embodied energy of materials included in the envelope is also increasing. Natural fibers like wood and hemp are used to make low environmental impact insulation products. Technical characterizations of five bio-based materials are described and compared to a common, traditional, synthetic-based insulation material, i.e., expanded polystyrene. The study tests the thermal conductivity and the vapor transmission performance, as well as the combustibility of the material. Achieving densities below 60 kg/m3, wood and hemp batt insulation products show thermal conductivity in the same range as expanded polystyrene (0.036 kW/mK). The vapor permeability depends on the geometry of the internal structure of the material. With long fibers are intertwined with interstices, vapor can diffuse and flow through the natural insulation up to three times more than with cellular synthetic (polymer) -based insulation. Having a short ignition times, natural insulation materials are highly combustible. On the other hand, they release a significantly lower amount of smoke and heat during combustion, making them safer than the expanded polystyrene. The behavior of a bio-based building envelopes needs to be assessed to understand the hygrothermal characteristics of these nontraditional materials which are currently being used in building systems.

Effect of Operating Temperatures on Thermal Conductivity of Polystyrene Insulation Material: Impact on Envelope-Induced Cooling Load

2014 ◽  
Vol 564 ◽  
pp. 315-320 ◽  
Author(s):  
Maatouk Khoukhi ◽  
Mahmoud Tahat
Keyword(s):  
Thermal Conductivity ◽  
Thermal Insulation ◽  
Energy Performance ◽  
Building Envelope ◽  
Insulation Material ◽  
Cooling Load ◽  
Thermal Insulation Material ◽  
Insulation Materials ◽  
Energy Performance Of Buildings ◽  
The Impact

The impact of the thermal conductivity (k-value) change of polystyrene insulation material in building envelope due to changes in temperature on the thermal and energy performance of a typical residential building under hot climate is investigated. Indeed, the thermal and energy performance of buildings depends on the thermal characteristics of the building envelope, and particularly on the thermal resistance of the insulation material used. The thermal insulation material which is determined by its thermal conductivity, which describes the ability of heat to flow cross the material in presence of a gradient of temperature, is the main key to assess the performance of the thermal insulation material. When performing the energy analysis or calculating the cooling load for buildings, we use published values of thermal conductivity of insulation materials, which are normally evaluated at 24°C according to the ASTM standards. In reality, thermal insulation in building is exposed to significant and continuous temperature variations, due essentially to the change of outdoor air temperature and solar radiation. Many types of insulation materials are produced and used in Oman, but not enough information is available to evaluate their performance under the prevailing climatic condition. The main objective of this study is to investigate the relationship between the temperature and thermal conductivity of various densities of polystyrene, which is widely used as building insulation material in Oman. Moreover, the impact of thermal conductivity variation with temperature on the envelope-induced cooling load for a simple building model is discussed. This work will serve as a platform to investigate the effect of the operating temperature on thermal conductivity of other building material insulations, and leads to more accurate assessment of the thermal and energy performance of buildings in Oman.

scholarly journals Prospects for the Application of Wavelet Analysis to the Results of Thermal Conductivity Express Control of Thermal Insulation Materials

Energies ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 5223
Author(s):  
Oleksandra Hotra ◽  
Svitlana Kovtun ◽  
Oleg Dekusha ◽  
Żaklin Grądz
Keyword(s):  
Thermal Conductivity ◽  
Wavelet Transform ◽  
Data Processing ◽  
Thermal Insulation ◽  
Control Method ◽  
Measurement Data ◽  
Conductivity Measurement ◽  
Differential Method ◽  
Expanded Polystyrene ◽  
Insulation Materials

This article discusses an express control method that allows in situ measurements of the thermal conductivity of insulation materials. Three samples of the most common thermal insulation materials, such as polyurethane, extruded polystyrene, and expanded polystyrene, were studied. Additionally, optical and organic glasses were investigated as materials with a stable value of thermal conductivity. For the measurement of thermal conductivity, the express control device, which implements the differential method of local heat influence, was used. The case studies were focused on the reduction of fluctuations of the measured signals caused by different influencing factors using wavelet transform. The application of wavelet transform for data processing decreased the thermal conductivity measurement’s relative error for organic glass SOL and optical glasses TF-1 and LK-5. The application of wavelet transform thermal conductivity measurement data for polyurethane, extruded polystyrene, and expanded polystyrene allowed to reduce twice the duration of express control while maintaining the same level of measurement error. The results of the investigation could be used to increase the accuracy in express control of the thermal conductivity of insulation materials by improving the data processing. This approach could be implemented in software and does not require a change in the design of the measuring equipment or the use of additional tools.

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