Rigid polyurethane foam
Density of rigid polyurethane foam
40 kg/m³ (30–60)
0.04 g/cm³ · 2.5 lb/ft³
The best-performing common insulator, at about 0.023 W/(m·K) — roughly a third better than the same thickness of expanded polystyrene, which is why a fridge wall can be thin. That figure depends on the blowing gas trapped in the closed cells and worsens over decades as the gas is replaced by air. Being a thermoset it has no melting point; heated far enough it chars and gives off isocyanates, which is why cutting it hot is a ventilation problem.
Properties
- Density
- 40 kg/m³ (30–60) — 0.04 g/cm³
- Tensile strength
- 0.2–0.6 MPa
- Young's modulus
- 0.01 GPa
- Thermal conductivity
- 0.023 W/(m·K)
- Floats in water
- Yes
- Magnetic
- No
What it is used for
- Refrigerator and freezer wall insulation
- Insulated roof and wall panels
- Expanding gap-filling foam
- Model making and tooling board
How it compares
Water is 1,000 kg/m³. Anything with a shorter bar than water floats in it.
air 1.2 kg/m³
expanded polystyrene foam 20 kg/m³
rigid polyurethane foam 40 kg/m³
Water — the float line 1,000 kg/m³
tungsten 19,250 kg/m³
gold 19,300 kg/m³
platinum 21,450 kg/m³
| Material | Density | Relative to water |
|---|---|---|
| expanded polystyrene foam | 20 kg/m³ | 0.02× |
| air | 1.2 kg/m³ | 0.00× |
| rigid polyurethane foam ← | 40 kg/m³ | 0.04× |
| platinum | 21,450 kg/m³ | 21.45× |
| gold | 19,300 kg/m³ | 19.30× |
| tungsten | 19,250 kg/m³ | 19.25× |
Does it rust?
Rigid polyurethane foam contains no iron, so it cannot rust. Whether it degrades depends on the material, not on oxidation.
Is it magnetic?
Rigid polyurethane foam is not a metal and has no ferromagnetic response.
Common questions
- What is the density of rigid polyurethane foam?
- 40 kg/m³ (30–60), or 0.04 g/cm³.
- Does rigid polyurethane foam float?
- Yes. At 40 kg/m³ it is less dense than water's 1,000.
- Is rigid polyurethane foam magnetic?
- Rigid polyurethane foam is not a metal and has no ferromagnetic response.
Related pages
- Does rigid polyurethane foam float? Yes
- PLA 1,240 kg/m³
- ABS 1,050 kg/m³
- Acrylic (PMMA) 1,180 kg/m³
- Polycarbonate 1,200 kg/m³
- Polypropylene 905 kg/m³
- PTFE 2,170 kg/m³
- Rigid PVC 1,400 kg/m³
- HDPE 955 kg/m³
Sources
- Typical range compiled from manufacturer specifications — At One Place