What is the difference between closed cell polyurethane foam and open cell polyurethane foam?
One-component polyurethane foam compositions, known under the name of installation foam, are more commonly used at household level, as well as for carrying out operations with limited areas and volumes (filling cracks, small openings, carrying out repair work, etc.).
In fact, the components are already premixed and the composition required for polymerization is located in a pressurized tank. But for the final reaction, foaming and hardening, contact with oxygen and water in the air is required (wetting the surface and the water vapor contained in the air). The result is a porous foam structure whose pores are open.
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Specificataion |
compare |
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closed cell polyurethane /Two-component spray foam |
open cell polyurethane foam / spray foam |
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Thermal conductivity, W/m x℃ |
0,019 ÷ 0,035 |
0,025 ÷ 0,045 |
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Number of closed cells |
Above 90% |
Below 50% |
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Expansion (bubble rise) compared to original volume |
1：40 |
1：70 ÷ 90 |
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Density, kilogram/cubic meter |
20 ÷ 200 |
8 ÷ 18 |
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vapor transmission rate |
0,02 ÷ 0,05 |
0,07 ÷ 0,15 |
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Hygroscopicity |
1 ÷ 3% |
10 ÷ 60% |
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Waterproof performance |
yes |
no |
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Sound absorption performance |
good |
high |
Two different techniques can be used to create an insulating structure or to impart insulating properties to building elements - spraying or filling of cavities (casting).