Performance characteristics of polyurethane foam materials

Polyurethane foam material is a high-performance molecular material with a porous structure. Its performance characteristics vary significantly due to different regions and processes. The following are its main features:

1. Lightweight and highly cushioned

Low density: The density can be as low as 20 kg/m ³ (soft foam) or 30-200 kg/m ³ (hard foam), and it is lightweight.

Excellent cushioning: perforated soft foam (such as memory foam) absorbs impact energy and is suitable for packaging, seat cushions, etc.

2. Outstanding insulation performance

Low thermal conductivity (0.018-0.035 W/(m · K)), closed cell rigid foam is widely used for building insulation (such as walls, refrigerator insulation layers).

Wide temperature adaptability (-50 ℃~120 ℃), can be used for cold chain and pipeline insulation.

3. Adjustable mechanical properties

Soft foam: Good elasticity and tensile strength (such as insoles and car seats).

Hard foam: high rigidity, compressive strength up to 200-500 kPa, suitable for structural filling (such as sandwich panels).

4. Chemical and performance stability

Resistant to solvents and oils, but some models are prone to hydrolysis (requiring the addition of stabilizers).

Aging resistance: With UV protection through additives, the outdoor service life can reach more than 10 years.

5. Acoustics and sound absorption performance

The perforated structure has excellent absorption of mid to high frequency sound waves (NRC can reach 0.6-0.9), and is used in recording studios and car interiors.

6. Flame retardancy and safety

The ordinary model is flammable (with an oxygen index of about 18%), but it can be upgraded to B1 level (with an oxygen index of ≥ 26%) by adding flame retardants (such as phosphorus and halogen compounds), meeting the requirements of building fire prevention (based on actual reports).

7. Environmental friendliness

Traditional areas contain VOCs, while new water-based/bio based polyurethanes (such as soybean oil derivatives) are more environmentally friendly.

Recycling difficulty: Chemical cross-linking structures are difficult to degrade, but physical recycling (crushing and bonding) has been used for carpet lining, etc.

8. Process adaptability

On site foaming: spraying, pouring and molding, fitting complex shapes (such as roof insulation, car cavity filling).

Suitable speed for curing: molding in a few minutes, suitable for automated production.

Application scenarios

Architecture: SPF spray insulation (closed cell), insulation board.

Transportation: Car seats (high rebound soft foam), interior sound-absorbing cotton.

Household appliances: refrigerator insulation layer (cyclopentane foam hard foam).

Diagnosis and treatment: The specific focus is on the actual use of soft foam for mattresses and orthopedic equipment.