Rigid Polyurethane Foam Thermal Insulation Protected with Mineral Intumescent Mat

Abstract One of the biggest disadvantages of rigid polyurethane (PU) foams is its low thermal resistance, high flammability and high smoke production. Greatest advantage of this thermal insulation material is its low thermal conductivity (λ), which at 18-28 mW/(m•K) is superior to other materials. To lower the flammability of PU foams, different flame retardants (FR) are used. Usually, industrially viable are halogenated liquid FRs but recent trends in EU regulations show that they are not desirable any more. Main concern is toxicity of smoke and health hazard form volatiles in PU foam materials. Development of intumescent passive fire protection for foam materials would answer problems with flammability without using halogenated FRs. It is possible to add expandable graphite (EG) into PU foam structure but this increases the thermal conductivity greatly. Thus, the main advantage of PU foam is lost. To decrease the flammability of PU foams, three different contents 3%; 9% and 15% of EG were added to PU foam formulation. Sample with 15% of EG increased λ of PU foam from 24.0 to 30.0 mW/(m•K). This paper describes the study where PU foam developed from renewable resources is protected with thermally expandable intumescent mat from Technical Fibre Products Ltd. (TFP) as an alternative to EG added into PU material. TFP produces range of mineral fibre mats with EG that produce passive fire barrier. Two type mats were used to develop sandwich-type PU foams. Also, synergy effect of non-halogenated FR, dimethyl propyl phosphate and EG was studied. Flammability of developed materials was assessed using Cone Calorimeter equipment. Density, thermal conductivity, compression strength and modulus of elasticity were tested for developed PU foams. PU foam morphology was assessed from scanning electron microscopy images.

Download Full-text

Development of Renewable Feedstock Based Rigid Polyurethane Foam and Nanoclay Composites

10.7250/9789934224706 ◽

2020 ◽

Author(s):

◽

Miķelis Kirpļuks

Keyword(s):

Mechanical Properties ◽

Thermal Insulation ◽

Flame Retardants ◽

Polyol Synthesis ◽

Insulation Material ◽

Pu Foam ◽

Renewable Feedstock ◽

Pu Foams ◽

Impact Absorption ◽

Halogenated Flame Retardants

Rigid PU foams are versatile material commonly applied as a thermal insulation material. It can be applied as an impact absorption material in the automotive industry if material with sufficient mechanical properties has been developed. Further increase in mechanical properties can be achieved by developing nano-reinforced rigid PU foams. Majority of commercially used rigid PU foams are produced from non-renewable petrochemical-based raw materials. Although, renewable feedstock, as well as recycled materials, can be used to obtain rigid PU foams with equal properties. In this work, several bio-based, as well as APP polyols, have been used to develop rigid PU foams. Rigid PU foam thermal insulation material has to fulfil demanding flammability requirements. This is achieved by the introduction of different flame retardants into the material structure from which most common are halogenated flame retardants. Halogenated flame retardants are associated with different health hazards, thus their phase-out from the market can be expected. A good alternative to halogenated flame retardants are intumescent flame retardant solutions. The results and discussion of this thesis are divided into three parts: Part 1 describes the development of high-density rigid PU foam material for application as impact absorption material in the automotive industry. Sustainable origin polyols have been used to develop rigid PU foams and their influence on mechanical, thermal and morphological properties of the material has been studied. To further increase mechanical properties of the rigid PU foams a nano-composite with montmorillonite nano-clay was developed. Lastly, most optimal rigid PU foam formulations were upscaled to produce real scale automotive part, which was tested according to the European Union’s crash test requirements. Part 2 describes the development of rigid PU foam thermal insulation from bio-based polyols. Halogenated flame retardants were replaced using non-halogenated alternatives. Intumescent flame retardants, such as expandable graphite was used to significantly reduce the flammability of the rigid PU foam. Part 3; during high-density rigid PU foam development it was discovered that used bio-based polyols have too low OH group functionality. Thus, the functionality of the polyols was increased by developing different bio-polyol synthesis method. Rapeseed oil, as well as tall oil, were used as feedstock for high functionality bio-based polyol synthesis. The first step was an epoxidation of the unsaturated moieties of the bio-based oils. Afterwards, oxirane ring opening with different polyfunctional alcohols and simultaneous transesterification/esterification reactions were used to obtain desired polyol structures.

Download Full-text

Cryogenic thermal insulating and mechanical properties of rigid polyurethane foams blown with hydrofluoroolefin: Effect of perfluoroalkane

Journal of Cellular Plastics ◽

10.1177/0021955x211062633 ◽

2021 ◽

pp. 0021955X2110626

Author(s):

Tae Seok Kim ◽

Yeongbeom Lee ◽

Chul Hyun Hwang ◽

Kwang Ho Song ◽

Woo Nyon Kim

Keyword(s):

Mechanical Properties ◽

Thermal Conductivity ◽

Thermal Stability ◽

Cell Size ◽

Thermal Insulation ◽

Coefficient Of Thermal Expansion ◽

Lower Surface ◽

Polyurethane Foams ◽

Insulation Material ◽

Pu Foams

The effect of perfluoroalkane (PFA) on the morphology, thermal conductivity, mechanical properties and thermal stability of rigid polyurethane (PU) foams was investigated under ambient and cryogenic conditions. The PU foams were blown with hydrofluorolefin. Morphological results showed that the minimum cell size (153 μm) was observed when the PFA content was 1.0 part per hundred polyols by weight (php). This was due to the lower surface tension of the mixed polyol solution when the PFA content was 1.0 php. The thermal conductivity of PU foams measured under ambient (0.0215 W/mK) and cryogenic (0.0179 W/mK at −100°C) conditions reached a minimum when the PFA content was 1.0 php. The low value of thermal conductivity was a result of the small cell size of the foams. The above results suggest that PFA acted as a nucleating agent to enhanced the thermal insulation properties of PU foams. The compressive and shear strengths of the PU foams did not appreciably change with PFA content at either −170°C or 20°C. However, it shows that the mechanical strengths at −170°C and 20°C for the PU foams meet the specification. Coefficient of thermal expansion, and thermal shock tests of the PU foams showed enough thermal stability for the LNG carrier’s operation temperature. Therefore, it is suggested that the PU foams blown by HFO with the PFA addition can be used as a thermal insulation material for a conventional LNG carrier.

Download Full-text

Sustainable insulating foams based on recycled polyurethanes from construction and demolition wastes

Open Research Europe ◽

10.12688/openreseurope.13288.2 ◽

2021 ◽

Vol 1 ◽

pp. 37

Author(s):

Edurne Elorza ◽

Ibon Aranberri ◽

Xiangming Zhou ◽

Gediminas Kastiukas ◽

Juan Antonio Alduncin

Keyword(s):

Thermal Conductivity ◽

Thermal Insulation ◽

Industrial Wastes ◽

Raw Material ◽

Infrared Analysis ◽

Compression Properties ◽

Pu Foam ◽

Construction And Demolition Wastes ◽

Low Levels ◽

Pu Foams

Background: Polyurethane (PU) foams contained in construction and demolition wastes (CDW) represent a great environmental impact, since they usually end in landfill or incineration processes. The goal of this work is to develop a way to formulate PU foams, maintaining (or ever improving) their performance, by the re-use of those industrial wastes. This procedure will allow minimize both the volume of disposal to be treated by other ways and the amount of pristine raw material needed to produce new PU foams. Methods: In this work, new rigid and soft polyurethane (PU) foams have been formulated with addition of recycled PU foams coming from demolition of buildings. Density, Fourier transform infrared analysis, compression properties and thermal conductivity were measured to characterize the resulting foams. Results: The work showed that addition of filler coming from recycled PU foams should be limited to low percentages, in order to allow good foam evolution from the reactants. Thermal conductivity values of modified rigid foams are worse than those of pristine foam, which is undesirable for thermal insulation purposes; however, in the case of soft foams, this parameter improved to some extent with low levels of recycled PU foam addition. Conclusions: The studied procedure could contribute to reduce the thermal conductivity of pristine soft PU foam, which would be of interest for applications where thermal insulation matters.

Download Full-text

Sustainable insulating foams based on recycled polyurethanes from construction and demolition wastes

Open Research Europe ◽

10.12688/openreseurope.13288.1 ◽

2021 ◽

Vol 1 ◽

pp. 37

Author(s):

Edurne Elorza ◽

Ibon Aranberri ◽

Xiangming Zhou ◽

Gediminas Kastiukas ◽

Juan Antonio Alduncin

Keyword(s):

Thermal Conductivity ◽

Thermal Insulation ◽

Industrial Wastes ◽

Raw Material ◽

Infrared Analysis ◽

Compression Properties ◽

Pu Foam ◽

Construction And Demolition Wastes ◽

Low Levels ◽

Pu Foams

Download Full-text

Unused Plant Waste and Thermal Insulation Composition Boards on their Basis

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.887.480 ◽

2021 ◽

Vol 887 ◽

pp. 480-486

Author(s):

T.N. Vachnina ◽

I.V. Susoeva ◽

A.A. Titunin ◽

S.V. Tsybakin

Keyword(s):

Thermal Conductivity ◽

Thermal Insulation ◽

Wood Fiber ◽

Mineral Wool ◽

Wood Waste ◽

Insulation Material ◽

Plant Fibers ◽

Coefficient Of Thermal Conductivity ◽

Plant Waste ◽

Technology Of Production

Many plant wastes are not currently used in production, they are disposed of in landfills or incinerated. The aim of this study is to develop a composite thermal insulation material from unused spinning waste of flax and cotton fibers and soft wood waste. Samples of thermal insulation materials from plant waste were made by drying using the technology of production of soft wood fiber boards. For composite board defined physico-mechanical characteristics and thermal conductivity. The experiment was carried out according to a second-order plan, regression models of the dependences of the material indicators on the proportion of the binder additive, drying temperature and the proportion of wood waste additives were developed. The study showed that composites from unused spinning waste of plant fibers and soft wood waste have the necessary strength under static bending, the swelling in thickness after staying in water is much lower in comparison with the performance of boards from other plant fillers. The coefficient of thermal conductivity of the boards is comparable with the indicator for mineral wool boards.

Download Full-text

The Development and Application of Non-Shrinking Composite Silicate Insulation Material

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.772.178 ◽

2013 ◽

Vol 772 ◽

pp. 178-181

Author(s):

Yong Liang Zhan ◽

Hai Yang Chen ◽

Xing Hua Hou ◽

Fei He

Keyword(s):

Thermal Conductivity ◽

High Temperature ◽

Production Process ◽

Thermal Insulation ◽

Raw Materials ◽

Drying Shrinkage ◽

Structural Member ◽

Insulation Material ◽

Technical Performance

Non-shrinking composite silicate insulation material has advantages of low drying shrinkage, density, thermal conductivity and good thermal insulation which withstands high temperature and militates in favor of specially shaped structural member construction, etc. This article describes raw materials and the production process of the above material, discusses thermal insulation characteristics, technical performance and the features of use and particularizes the application effect in the project.

Download Full-text

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

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.564.315 ◽

2014 ◽

Vol 564 ◽

pp. 315-320 ◽

Cited By ~ 8

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.

Download Full-text

A Novel Building Thermal Insulation Material: Expanded Perlite Modified by Aerogel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.250-253.507 ◽

2011 ◽

Vol 250-253 ◽

pp. 507-512

Author(s):

Zi Sheng Wang ◽

Hao Chi Tu ◽

Jin Xiu Gao ◽

Guo Dong Qian ◽

Xian Ping Fan ◽

...

Keyword(s):

Thermal Conductivity ◽

Mechanical Property ◽

Thermal Insulation ◽

Production Cost ◽

Building Materials ◽

Low Cost ◽

Insulation Material ◽

Expanded Perlite ◽

Thermal Insulation Material ◽

Supercritical Fluid Drying

Aerogel is regarded as one kind of super thermal insulation materials which could be large-scalely used as building materials. However, the aerogel’s production cost and poor mechanical property limit the its applications. In this paper, we put forward a new low cost way to produce a novel building thermal insulation material: synthesized the aerogel within the expanded perlite’s pores, and using sodium silicate as precursor without adopting supercritical fluid drying and surface modification. The thermal conductivity of expanded perlite was successfully decreased after modified by aerogel.

Download Full-text

Thermal Insulation and Mechanical Properties of Polylactic Acid (PLA) at Different Processing Conditions

Polymers ◽

10.3390/polym12092091 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2091

Author(s):

Mohamed Saeed Barkhad ◽

Basim Abu-Jdayil ◽

Abdel Hamid I. Mourad ◽

Muhammad Z. Iqbal

Keyword(s):

Thermal Conductivity ◽

Compressive Strength ◽

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Polylactic Acid ◽

Thermal Insulation ◽

Annealing Time ◽

Insulation Material ◽

Thermal Insulation Material

This work aims to provide an extensive evaluation on the use of polylactic acid (PLA) as a green, biodegradable thermal insulation material. The PLA was processed by melt extrusion followed by compression molding and then subjected to different annealing conditions. Afterwards, the thermal insulation properties and structural capacity of the PLA were characterized. Increasing the annealing time of PLA in the range of 0–24 h led to a considerable increase in the degree of crystallization, which had a direct impact on the thermal conductivity, density, and glass transition temperature. The thermal conductivity of PLA increased from 0.0643 W/(m·K) for quickly-cooled samples to 0.0904 W/(m·K) for the samples annealed for 24 h, while the glass transition temperature increased by approximately 11.33% to reach 59.0 °C. Moreover, the annealing process substantially improved the compressive strength and rigidity of the PLA and reduced its ductility. The results revealed that annealing PLA for 1–3 h at 90 °C produces an optimum thermal insulation material. The low thermal conductivity (0.0798–0.0865 W/(m·K)), low density (~1233 kg/m3), very low water retention (<0.19%) and high compressive strength (97.2–98.7 MPa) in this annealing time range are very promising to introduce PLA as a green insulation material.

Download Full-text

Studies of the Influence of Graphite on the Physical Mechanical and Thermal Properties of Polyurethane Foams for Construction Applications

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.887.399 ◽

2021 ◽

Vol 887 ◽

pp. 399-405

Author(s):

L.N. Shafigullin ◽

N.V. Romanova ◽

G.R. Shafigullina

Keyword(s):

Thermal Conductivity ◽

Thermal Properties ◽

Absorption Coefficient ◽

Sound Absorption ◽

Polyurethane Foams ◽

Onset Temperature ◽

Sound Absorption Coefficient ◽

Expandable Graphite ◽

Mechanical And Thermal Properties ◽

Pu Foam

The paper shows the applicability of expandable graphite METOPAC EG 350-50 (80) in a rigid PU foam system as a substance that reduces the flammability (flame retardant) and improves the usability. The studies of the physical mechanical and thermal properties of PU foam with a higher graphite content revealed a higher normal sound absorption coefficient; insignificant influence on the thermal conductivity; a higher decomposition onset temperature; more difficult ignition. PU foam sample with a ratio of 15 graphite weight fractions to 100 polyol weight fractions has the highest physical mechanical and thermal properties, and, as compared to the starting PU foam, it features an increase in normal sound absorption coefficient by an average of 3 times; a decrease in the thermal conductivity by 8 %; an increase in the decomposition onset temperature by 6.7 °С. Therefore, the modification of PU foam with expandable graphite makes it possible not only to develop hardly combustible polyurethanes but also to improve its physical mechanical and thermal properties.

Download Full-text