starting materials for insulation materials made of polyurethane foam are petroleum but also renewable resources, such as sugar beets, corn or potatoes. Intermediates in the production of polyurethane products are oil polyisocyanate and polyol. Rigid polyurethane foam is formed by chemical reaction of liquid raw materials with the addition of blowing agents. The blowing agent is used in Germany mainly pentane, small amounts of CO2, HCFC rare. The development in the area of the propellant is still ongoing. PUR rigid foam insulation boards are produced industrially either by the double belt process or as a block after block of foam process.
the double belt process is the effluent from the mixing head reaction mixture onto the bottom layer of the double belt system distributed. The foaming mixture stuck to the bottom and the top layer. The band foam panels can be produced in any quantity. As mineral fleece layers, glass fiber, paper, metal or composite sheets, roofing sheets are used.
flows At block foam method, the reaction mixture from a mixing head in a block or on a continuous block band. After foaming and deposition blocks are cut into boards or processed into molded parts (eg wedges, pipe bowls).
After the double belt process also PUR-sandwich panels with rigid facings (Eg, metal sandwich panels) made. Furthermore, even polyurethane integral foam parts are produced in special shapes.
insulation properties of rigid polyurethane foam are predominantly closed, rigid. The closed cell is> 90%. Polyurethane foam is alterungsbestädig, mold and fäulnisresistend not verrotet and has no affinity for plasticized films (PVC films). By dense gas diffusion layers obtained rigid polyurethane foam has a 025th of WLG
characteristics
thermal conductivity λ (R): 0.020 to 0.030 W / (mK)
spec. Heat capacity c: 1200-1400 J / (kg * K)
water vapor diffusion resistance μ: 30-150 (∞ with gas diffusion-tight outer layers vapor tight)
Building Class: B 2 flame retardant
temperature: 90 ° C (long term)
250 ° C (short term)
density ρ: 30-35 kg / m³
compressive strength:> 0, 10 /> 0.15 N / mm ²
linear expansion coefficient of 5-8 x 10 ^ -5 1 / K
Primary Energy: 800-1500 kWh / m³
application roof rafter
ceiling: floor insulation, basement ceiling insulation
Keller: partly as perimeter insulation
insulation for installation cables (heating) a thermal conductivity of 0.020
comments W / (mK) is only achieved through the use of HCFCs in connection with dense gas diffusion layers.
came until 1993 in the production of ozone-depleting CFCs nor the PUR R II is used, is dispensed with its use now. After change of CFC production by the propellant was pentane, isopentane, CO2 and replacing less and less used hydrochlorofluorocarbons HCFCs.
environmental aspects + commodities partly produced from natural products
- no known recycling methods for used plates, not biodegradable, burns may be CFCs released during fires, possibly toxic gases, high energy consumption during production
DIN EN 13165:2001-10
Thermal insulation products for buildings - Factory made products of rigid polyurethane foam (PUR) products - Specification; German version EN 13165:2001
DIN 18 164 part 1 (August 1992),
foam plastics as insulating materials for construction purposes;
insulation products for thermal insulation
ÖNORM EN 13165
thermal insulation products for buildings - Werkmaessig made products of rigid polyurethane foam
RAL-RG 710 / 2, Edition :1994-01
plastic foam - polyurethane foam slabs and paving as insulating materials for building applications - Quality Assurance
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