Thermal Insulation Panels Research Articles

Harnessing carboxymethyl cellulose as eco-binder to transform polyester textile waste into high-performance fire-resistant thermal insulation panels

This study aims to investigate the applicability of carboxymethyl cellulose (CMC) as a binder in insulating panels made from polyester textile waste (PTW), which is the most produced textile waste worldwide. This combination addresses the pressing need to recycle a widely manufactured material while introducing CMC as an environmentally friendly solution for elaborating panels with excellent thermal insulation and fire resistance. The composite panels were manufactured using compression molding process. The resulting thermal insulation panels demonstrate excellent thermal conductivity values, ranging from 0.0499 to 0.0514 W/m.K, comparable to established insulation materials. Panels with increased CMC content show remarkable mechanical strength, with compressive strengths of 217 kPa and 351 kPa for samples S4 and S5, respectively, and a flexural strength of 1.58 MPa for sample S5. This emphasizes that CMC as a binder helps distribute stresses more evenly across the composite, leading to higher strength and stiffness. Furthermore, employing CMC in the composite preparation confers exceptional resistance to flame propagation, namely, samples S4 and S5 exhibited immediate self-extinguishing properties and resistance to flame propagation. Accordingly, the mechanism behind CMC ability to resist flame propagation was investigated. Despite the composite's remarkable characteristics, its water sensitivity remains a disadvantage. Therefore, this shortcoming has been addressed highlighting several strategies that can be employed to mitigate CMC sensitivity to water including applying a waterproof coating to improve the composite humidity and water resistance increasing its overall durability.

Efficient Bio-Based Insulation Panels Produced from Eucalyptus Bark Waste

Traditional thermal insulation panels consume large amounts of energy during production and emits pollutants into the environment. To mitigate this impact, the development of bio-based materials is an attractive alternative. In this context, the characteristics of the Eucalyptus fiber bark (EGFB) make it a candidate for insulation applications. However, more knowledge about the manufacturing process and in-service performance is needed. The present study characterized the properties that determine the in-service behavior of the EGFB insulation panel. The assessment involved two different manufacturing processes. The results indicated that the hot plates and the saturated steam injection manufacturing system can produce panels with similar target and bulk density. The thermal conductivity fluctuated between 0.064 and 0.077 W/m·K, which indicated good insulation, and the values obtained for thermal diffusivity (0.10–0.37 m mm2/s) and water vapor permeability (0.032–0.055 m kg/GN s) are comparable with other commercially available panels. To guarantee a good in-service performance, the panels need to be treated with flame retardant and antifungal additive. The good performance of the panel is relevant because bio-based Eucalyptus bark panels generate less CO2 eq and require less energy consumption compared to traditional alternatives, contributing to the sustainability of the forestry and the construction industry.

Experimental investigation on the thermal characteristics of Kevlar/hemp intraply hybrid composites: Influence of various weaving designs

In this work, several weaving designs of intra-ply woven fabric Kevlar/hemp fiber (KHE) reinforced epoxy hybrid composites are developed and their thermal characteristics are examined. Thermogravimetric analysis showed that intra-ply hybrid of plain and basket weave designs possessed highest thermal stability. The different weaving patterns of KHE hybrid composites have no effect on the glass transmission temperature (Tg) value as inferred from the differential scanning calorimetry results. The thermomechanical analysis clearly demonstrates the superior dimension stability of the hybrid composites with basket weave. Dynamic mechanical analysis reveals that twill weave KHE have exhibited the maximum storage modulus (2021 MPa), loss modulus (210 MPa) and lower tan delta (0.3090) values compared to all other composites. Based on the obtained results, it is denoted that all the fabricated KHE hybrid composites displayed improved thermal performance. It may be suitable for applications in thermal insulation panels, fire-resistant clothing, and automotive underbody shields.

Experimental and numerical study on the shear performance of stainless steel-GFRP connectors for use in precast concrete sandwich panels

Precast Concrete Sandwich Panel (PCSP) is composed of concrete load-bearing panels, thermal insulation panels, and decorative panels, which are assembled through connectors, integrating load-bearing, thermal insulation, and decorative functions. The connector bears the main shear force between the wall panels, and the shear resistance and insulation performance of the connector largely determine the mechanical stability and insulation effect of the wall panels, which is a key component in PCSPs. The current common practice is to cross assemble stainless steel insulation (SSI) connectors and Glass-Fiber-Reinforced Plastic (GFRP) connectors into PCSPs, which can reduce building energy consumption and save resources while meeting strength and insulation requirements. A large-scale pull-out test on a PCSP with intersecting SSI-GFRP connectors was conducted in this paper. The damage process and damage pattern of PCSP were observed and the shear performance of SSI-GFRP connectors was analyzed. Secondly, a numerical analysis model of the test PCSP was built using ABAQUS finite element software and its validity was verified through the test data. In addition, parameters such as connector diameter, connector number ratio and concrete strength were analyzed for their effect on the shear performance of SSI-GFRP connectors and it was found that connector diameter and connector number ratio had a significant effect. Finally, it is found that there are some differences between the classical theory for calculating the shear performance of SSI-GFRP connectors and the actual results. A theoretical correction factor (ζ) is given to improve the accuracy of the calculation of the classical theory, and its influencing factors and changing rules are investigated.

Evaluation Research on Energy-Saving Retrofitting of Roofs of Traditional Wood-Structured Dwellings Based on the Continuation of Historical Features: A Case Study of Guangdu Village No. 280 Dwelling in Zhejiang

China has numerous traditional wooden dwellings located in regions with hot summers and cold winters. The historic dwellings lack proper thermal insulation and have excessive energy consumption in the building structure, failing to suit the needs of modern people. Hence, it is crucial to enhance their energy efficiency through essential actions. Roofs, being the fifth side of the building envelope, are frequently neglected when it comes to enhancing their insulating capabilities. The study aimed to implement energy-efficient roof alterations while preserving the historical features of traditional structures. This study focuses on enhancing the energy efficiency of a traditional wood-structured dwelling in Guangdu Village, Zhejiang Province, China, by installing composite thermal insulation panels on the interior of the roof using an easy restoration approach. The actual risk of condensation and the impact of retrofit processes on historical features determine the choice and limitations of energy-saving retrofit materials and methods. This study evaluates the transformation using two indicators: energy efficiency and economic feasibility. The numerical simulation results indicate that traditional dwellings have an annual energy savings rate of 16.66% and an investment payback period of 7.25 years. This study demonstrates the feasibility of energy-saving roof renovation measures for these traditional wood-structured dwellings. The measures improve energy efficiency and are affordable for residents. This study can offer technical suggestions for enhancing the energy efficiency of traditional wood-structured dwellings.

Utilizing discarded face masks to fabricate sustainable high-performance panels for enhanced building thermal and acoustic comfort

This study aims to design, fabricate, and optimize fibrous panels made of discarded polypropylene face masks (FMs) for application in sound absorption and thermal insulation. The discarded FMs were shredded and transformed into a fibrous mass using a Garnet machine. The resulting fibers, after being mixed with a bio-based binder, were molded based on an experimental design using response surface methodology in conjunction with the central composite experiment design (RSM-CCD) with five different thicknesses, densities, and blending ratios of spunbond to meltblown fabrics. The average of the sound absorption coefficients for the twelve one‐third‐octave bands from 200 to 2500 Hz (SAA) and effective thermal conductivity (Keff) of the panels were measured as the dependent parameters. These values were calculated within the ranges of 0.28–0.53 and 0.031–0.056 W/(mK), respectively. Additionally, the interactive effects of input variables on SAA and Keff of the manufactured panels were discussed. The quadratic and two-factor interaction models were proposed for optimizing the values of SAA and Keff, respectively. The optimal conditions were determined to achieve the maximum SAA and minimum Keff in a thickness of 26.7 mm, density of 135 kg/m3, and blending percentage of 32.4 %. Under these conditions, the measured values of SAA and Keff were 0.534 and 0.0279 W/mK, respectively. Finally, three fibrous panels were manufactured under optimal conditions, and their acoustic and thermal properties were measured. It was observed that excellent agreement exists between the model results and the experimental data with a 95% confidence level. The bending properties of the optimally designed panels were also investigated and the panels exhibited an impressive flexural strength of 2.1 MPa. Additionally, the fire performance of the panels was examined and all panels showed self-extinguishing properties. These findings suggest that panels made of discarded FMs hold promise as an eco-friendly and sustainable construction material for manufacturing acoustic and thermal insulation panels. Moreover, the frequency-dependent absorption coefficients of the panels were predicted using the Johnson-Champoux-Allard model.

Thermal Insulation Panels with Bio-Based Adhesives

Environment friendly insulation panels were manufactured and tested made of pine wood fibers and glued with a bio-based adhesive, called dextran. The aim of this work was to determine relevant technical properties of panels fabricated with this new glue type. In the panels, the ratio of dry glue content was varied from 30% to 60% with 10% steps which runs served as comparison basis. The density of the insulation panels was set to 70 kg/m3, 100 kg/m3 and 125 kg/m3. Beside their thermal conductivity, the compression strength, the bonding strength, and the wetting angle of the adhesive were measured. With the variation of panel densities, the thermal conductivity is in a narrow range of 0.039 to 0.042 W/mK. The resistance to compression at 10% strain was measured to be 0.3 MPa, 0.35 MPa and 0.4 MPa in the panels with 70 kg/m3, 100 kg/m3 and 125 kg/m3, respectively. The wetting angle of the adhesives seemed to correlate only weakly with the bonding strength, and the glue`s wetting ability diminished with the increase of the glue content. The results seem to be competitive if compared with the traditionally used glass and rockwool, and foam insulation materials.

Influence of Anatomy, Microstructure, and Composition of Natural Fibers on the Performance of Thermal Insulation Panels.

The growing interest in environmentally friendly materials is leading to a re-evaluation of natural fibers for industrial applications in order to meet sustainability and low-cost objectives, especially for thermal insulation of buildings. This paper deals with the chemical and physical characterization of fibers extracted from seagrass (Posidonia oceanica) and alfa grass (Stipa tenacissima) for a possible substitution of synthetic materials for thermal insulation. Hemp (Cannabis sativa), a fiber broadly used, was also studied for comparison. The parameters characterized include porosity, thermal degradation, elemental composition, skeletal and particle density of the fibers as well as investigation of the thermal conductivity of fiber-based panels. Several technologies were involved in investigating these parameters, including mercury intrusion, thermogravimetric analysis, fluorescence spectroscopy, and fluid pycnometry. The fibers showed a degradation temperature between 316 and 340 °C for Posidonia, between 292 and 326 °C for alfa, and between 300 and 336 °C for hemp fibers. A high porosity allied with a reduced pore size was revealed for Posidonia (77%, 0.54 μm) compared to hemp (75%, 0.61 μm) and alfa (57%, 2.1 μm) raw fibers, leading to lower thermal conductivity values for the nonwoven panels based on Posidonia (0.0356-0.0392 W/m.K) compared to alfa (0.0365-0.0397 W/m.K) and hemp (0.0387-0.0427 W/m.K). Bulk density, operating temperature, and humidity conditions have been shown to be determining factors for the thermal performance of the panels.

Development of thermal insulation panels bio-composite containing cardboard and date palm fibers

This study aims to determine the thermal, acoustic, and hygroscopic properties of materials designed for building thermal insulation. These materials are composed of cardboard reinforced with fibers sourced from date palm trees. The composite formulation involves a mixture of 40% date palm components, including pinnate leaves, clusters, trunk petioles, and palm fibers, along with 60% cellulose-based cardboard waste. Water is used as the binding agent, eliminating the need for additional chemicals or additives.For the assessment, thermal conductivity, thermal diffusivity, normal transmission loss (TL), and the acoustic absorption coefficient were measured using the hot plane method, flash method and acoustic impedance tube, respectively. The results indicate that the developed composites have thermal conductivity values ranging from 0.074 to 0.081 W/m.K for a density ranging from 226.6 to 312.8 kg/m³. Additionally, the sound transmission loss coefficients exceed 5 dB in the frequency range of 500–1400 Hz, and the acoustic absorption coefficient is greater than 0.4 across a wide range of frequencies from low to high frequencies (200 Hz–1400 Hz). Furthermore, after 6 h of water immersion, a minimal capillary water absorption coefficient of 203% is achieved. What sets this study apart is the comprehensive life cycle cost analysis performed, shedding light on the sustainability of these materials. The optimization of insulation thickness was also conducted, determining optimal values based on climate conditions and energy sources. Overall, this innovative approach offers environmentally friendly and sustainable insulation options for the construction industry, integrating thermal and acoustic properties, life cycle cost analysis, and insulation thickness optimization.

Comparative analysis of thermal performance for precast panel systems with conventional and innovative insulation materials

ABSTRACT Precast facades are one of the most popular technology solutions featuring high-quality implementation and installation. They consist of three layers, both the external and internal layers are concrete composite, where the core is a thermal insulation material. This study explores the thermal performance improvement of these locally manufactured panels and evaluates their effectiveness in supporting building sustainability and energy saving. The study is performed experimentally. Leca and Addipor aggregates were used as a replacement of mix aggregate to produce lightweight heat-insulating concrete. Compressive strength equals 15MPa were taken for both Leca and Addipor replacement ratio. The study simulates several sections of precast concrete panels using ANSYS. Proposed concrete models with traditional and innovative thermal insulation materials, which are Expanded Polystyrene Foam (EPS), Extruded Polystyrene Foam (XPS), Rigid polyurethane foam (PU) and Vacuum insulation panels (VIPs), were analyzed. In addition, a virtual room space was simulated thermally using the previous sections to perform thermal simulations, as rate of heat transfer and amount of energy savings. The use of polyurethane foam (PU) as a new thermal insulation material and vacuum insulation panels (VIP) as an innovative thermal insulation material helps to reduce energy consumption by a rate of 143% and 700% of conventional insulation materials (EPS), respectively. It achieves internal thermal comfort and supports building sustainability.

Proposed method for design optimization of LNG tanks based on the arrangement of thermal insulation panels

During the building of an LNG tank, a thermal insulation panel, hereafter referred to as a “panel,” is installed on the inner wall to insulate the tank from external conditions. The inner wall of the LNG tank can experience deformations, leading to the panel becoming inclined and twisted, making it susceptible to damage and reducing its insulation effectiveness. To address this challenge, a common practice involves placing wedges at each corner of the panel between the inner tank wall and the panel, and then filling the resulting gaps with a mastic rope. However, this extensive use of mastic ropes to mitigate panel inclination and twisting is a costly solution.The primary objective of this study is to optimize the overall use of mastic ropes for enhanced tank insulation. This optimization is achieved by determining the ideal panel installation height, which is dependent on factors such as the wedge height, as well as panel inclination and twisting. These parameters serve as the objective functions and constraints for optimization.To validate the effectiveness and feasibility of the proposed method, tests were conducted by applying the proposed method to cover the inner wall of an LNG tank with insulation panels. The study considered four cases, each focusing on different objective functions related to the economic feasibility and safety of LNG tanks, and compared the results. In the most cost-effective solution, the total use of mastic ropes was reduced by approximately 42% compared to the conventional manual design. Furthermore, safety-related solutions demonstrated improved safety levels compared to the manual design, with only a marginal 0.1% change in the total use of mastic ropes. Lastly, in cases where both economic feasibility and safety were considered, improvements were observed in both aspects compared to the manual design.

Recycling of Waste Cartons and Musanga cecropioides Heartwood into Composite Panels for Structural Application

In this research, the suitability of composite panels developed from waste carton paste (WCP) and Musanga cecropioides heartwood particles (MHP) was assessed for structural applications. Proportions of the MHP adopted were 0, 25, 50, 75, and 100 % by weight of the composite mix. For each formulation, three representative samples were fabricated and also subjected to various tests. The results of the tests showed variations in the mean values of water absorption (8.83 – 30.35 %), thickness swelling (3.72 – 10.84 %), bulk density (342.3 – 461.6 kgm-3), thermal conductivity (0.1166 – 0.1717 Wm-1K-1), thermal diffusivity (2.051 – 2.397 x 10-7 m2s-1), and flexural strength (1.388 – 9.636 MPa) as proportion of the MHP decreased from 100 % to 0 %. On the contrary, a positive correlation was observed in the cases of specific heat capacity (1.552 – 1.661 x 103 Jkg-1K-1) and solar radiation absorptivity (12.32 – 13.32 m-1) with respect to increase in the proportions of the MHP used. Though all the samples exhibited better performance tendencies for thermal insulation compared to conventional ceilings or partition elements used in buildings, it was observed that samples developed with more than 50 % of the MHP could not withstand nailability. Above all, waste cartons and Musanga cecropioides heartwood are promising raw materials to be considered for fabrication of low-cost composite thermal insulation panels suitable for application in building designs. This undertaking could also serve as a safe way of managing them as wastes.

Valorization of Moroccan Hemp Waste: Study of the Possibility of its Use in Thermal and Acoustical Insulation of Buildings

This paper aims to study the possibility of valorizing hemp residues in order to develop new local bio-composites from Moroccan hemp shiv and epoxy. The goal is to use them as thermal and acoustical insulation panels since these hemp residues exist in large quantities in landfills and present a national concern due to a lack of waste management technologies. For this purpose, several samples were prepared for different densities and two sizes of hemp shiv; crushed shiv (CS) and fibred shiv (FS). The results revealed that the increase of density resulted in an increase in thermal conductivity and a decrease in thermal diffusivity. However, the thermal conductivity of composites is still lower than 0.1 W/mK for the most studied samples. The samples show values of acoustic absorption coefficients varying between 0.2 and 0.59 for crushed shiv composites (CSC) at the frequency range (578-1396 Hz) and between 0.2 and 0.73 at the frequency range (662-1396 Hz) for Fibred shiv composites (FSC). It has been observed that the density has a significant effect on the sound absorption coefficient. Increasing the density shifts the acoustic absorption curve towards the low frequencies. Also, decreasing the particle size enhances the sound absorption in the medium frequency range (300-600 Hz). The obtained results are satisfactory for manufacturing these new composites that can be used as thermal and acoustic insulators. Moreover, it offered the best solution for hemp waste management.

Design and analysis of the thermal-insulation panel for the test section of the environmental wind tunnel

Thermal-insulation panels are an important part of the test section for the environmental wind tunnel, which has the function of ensuring uniform airflow temperature and reducing heat loss. Considering many factors such as temperature, humidity, and pressure, it is determined that the average heat dissipation rate of the insulation panel’s outer surface temperature is less than 20 W/m2. The temperature difference between the outer surface of the insulation layer and the environment is not more than 10°C when the airflow temperature inside the test section reaches 95 °C. There is no condensation on the insulation layer when the airflow temperature inside the test section is -10 °C. By comparing various schemes, a phenolic foam was selected as the thermal-insulation material, and process measures such as liquid raw material mixing foaming and special equipment were adopted to complete the fabrication of the panels, and a composite assembly method was adopted to build panels in the test section. The results show that the thermal-insulation panel’s structure is conformed to the requirements of wind-tunnel operation and heat loss, which provides an important basis for reference for the construction of relevant test equipment.

WITHDRAWN: A facile refining approach: Production of composite thermal insulation panels using empty fruit bunch and spent mushroom substrate fibers

WITHDRAWN: A facile refining approach: Production of composite thermal insulation panels using empty fruit bunch and spent mushroom substrate fibers

The effect of thermal insulation from autoclaved aerated concrete on the energy performance of a single-family house

The article examines the effect of thermal insulation from autoclaved aerated concrete on the energy characteristics of a single-family house. Analysis of mathematical models of energy characteristics of external enclosing structures of buildings depending on the thickness of AEROC autoclaved concrete products according to the criteria of heat loss shows that the thermal resistance value of 7.11 m2K/W and the heat transfer coefficient of 0.141 W/(m2K) are achieved using the wall block AEROC D 300 and AEROC Energy thermal insulation panel with a thickness of 200 mm. These indicators correspond to the passive house standard for thermal resistance (Ro ≥ 6.7 m2K/W) and heat transfer coefficient (Uo ≤ 0.15 W/m2K) of external walls, which confirms the feasibility of using AEROC Energy D 150 thermal insulation panels in combination with wall blocks AEROC D 300 for housing construction according to passive construction standards.

Contribution to Active Thermal Protection Research—Part 2 Verification by Experimental Measurement

This article is closely related to the oldest article titled Contribution to Active Thermal Protection Research—Part 1 Analysis of Energy Functions by Parametric Study. It is a continuation of research that focuses on verifying the energy potential and functions of so-called active thermal protection (ATP). As mentioned in the first part, the amount of thermal energy consumed for heating buildings is one of the main parameters that determine their future design, especially the technical equipment. The issue of reducing the consumption of this energy is implemented in various ways, such as passive thermal protection, i.e., by increasing the thermal insulation parameters of the individual materials of the building envelope or by optimizing the operation of the technical equipment of the buildings. On the other hand, there are also methods of active thermal protection that aim to reduce heat leakage through nontransparent parts of the building envelope. This methodology is based on the validation of the results of a parametric study of the dynamic thermal resistance (DTR) and the heat fluxes to the interior and exterior from the ATP for the investigated envelope of the experimental house EB2020 made of aerated concrete blocks, presented in the article “Contribution to the research on active thermal protection—Part 1, Analysis of energy functions by the parametric study”, by long-term experimental measurements. The novelty of the research lies in the involvement of variant-peak heat/cooling sources in combination with RES and in creating a new, original way of operating energy systems with the possibility of changing and combining the operating modes of the ATP. We have verified the operation of the experimental house in the energy functions of thermal barrier, heating/cooling with RES, and without RES and ATP. The energy saving when using RES and ATP is approximately 37%. Based on the synthesis and induction of analogous forms of the results of previous research into recommendations for the development of building envelopes with energy-active elements, we present further possible outcomes in the field of ATP, as well as already realized and upcoming prototypes of thermal insulation panels.

Refined electromagnetic analysis of W7-X thermal insulation during fast plasma current decay event

During the second operation phase of the most advanced stellarator Wendelstein 7-X (W7-X) in 2018, a fast plasma current decay event was observed with the time constant of ∼1 ms. The event is much more rapid than the design phase assumptions: 100 kA and 2.7 MA plasma current decay with the time constants of 140 and 50 ms for toroidal and diamagnetic currents, respectively. As a result, significantly higher eddy currents are expected to be induced in some of the W7-X components. The comprehensive campaign of electromagnetic (EM) analyses has been launched in order to identify the necessity of proper reinforcement of critical in-vessel diagnostics or lowering the plasma currents for future operation. One of the critical W7-X system found is the complex thermal insulation (TI).The TI is located in the cryostat to separate cryogenically cooled magnet system and warm vessels. The system consists of actively cooled thermal radiation panels and port tubes, multi-layer insulations, supports and clamps. The TI panels and tubes form the main frame of TI covering the plasma vessel (PV) and ports, respectively. Preliminary EM analysis with few panels and tubes indicates that the EM forces are increased by about 7 times due to the newly postulated faster plasma current decay event in comparison with original design loads. To obtain more accurate results, an elaborated EM model has been created, which includes the excitation coils for toroidal and diamagnetic plasma currents, superconducting coils, TI panels and tubes, the PV and ports.The paper introduces at first the TI structure, continues with the field and eddy current accuracy studies and the lessons learned for the modelling accuracy improvement in ANSYS®. Then the EM analysis results of different plasma current decay scenarios are presented and discussed. Finally, the EM forces for static and transient mechanical analyses are chosen and extracted for further mechanical analyses.

Thermal and acoustic performance evaluation of 3D-Printable PLA materials

In this study, additive manufacturing or three dimensional (3D) printing technology was utilized to develop thermal and acoustic insulation materials. A 3D model was carefully designed to obtain thermal and acoustic insulation properties using Autodesk software and print the materials using QIDI X-PLUS 3D printer with precise and controlled shape and structure. Biodegradable PLA filament was used as printing ink. A comprehensive evaluation was conducted to check whether this new branch of technology is suitable for producing insulation materials. Testing results revealed that insulation materials produced from 3D printing technology have excellent thermal and acoustic insulation properties. The lowest obtained thermal conductivity value was 0.037 W/mK, and the maximum obtained sound transmission loss was 48.27 dB at 1600 Hz frequency. In case of physical properties, density of insulation panels ranges from 366.46 to 721.26 kg/m3, and porosity ranges from 43 to 71%. Life cycle cost (LCC) analysis was carried out to obtain the optimum insulation thickness, energy savings, and payback period of developed insulation materials for different locations in the USA. It was found that the optimum insulation thickness varies between 4 and 10 mm, energy savings varies between 45.0% and 67.2%, and payback period varies between 8.5 and 14.8 years. The effect of structural parameters (thickness, density, air permeability, and porosity) on insulation properties was also checked in order to obtain a relationship between structural parameters and insulation properties. It was found that both density and porosity have significant influence on insulation properties. Testing results also revealed that thermal and acoustic insulation properties follow opposite trends with the increase of density and porosity. The increase in density and decrease in porosity causes increase in acoustic insulation property, but decrease in thermal insulation property. A comparison was also made with commercially available acoustic and thermal insulation panels, and it was observed that produced 3D printed samples have better insulation properties. This indicates that developed materials have very good potential to be commercially used as building insulation materials. As produced insulation material has colored and glossy surfaces, it can be used in the interior or exterior of building walls and may also replace plasterboard or tiles of building walls.

Thermal insulation panels for buildings using recycled cardboard: Experimental characterization and optimum selection

Buildings contribute a major part to the energy use in the world. Thermal insulation of buildings is a passive strategy to achieve energy efficiency by reducing heating and cooling loads. Using recycled materials ensures efficient use of available resources by reducing material consumption. This study reports fabrication of thermal insulation panels using recycled cardboard aggregates and different biodegradable binders (corn starch, lime, clay) in varying percentage weight fractions and experimental characterization of their physical, thermal, mechanical and microstructural properties. Cardboard aggregates have been homogenized with binders and additives to fabricate nine panels. All the panels have reported good thermal conductivity values due to their porous nature, and sufficient compressive and flexural strength for use as thermal insulation in buildings. Strong adhesion between cardboard aggregates and cornstarch binder has been observed in SEM (Scanning Electron Microscope) analysis. This study also addresses selection of the optimum insulation material from various fabricated panels by considering the complex constraints that exist between physical, thermal and mechanical properties. Results of the study prove that the fabricated panels can be used for thermal insulation in buildings and can be further investigated for commercial use.