English
Views: 0 Author: Site Editor Publish Time: 2025-08-04 Origin: Site
Polyester polyols are key components in rigid polyurethane (PUR) and polyisocyanurate (PIR) foams used in sandwich panels for thermal insulation. Compared to polyether polyols, polyester-based systems offer higher thermal stability, better fire resistance, and improved mechanical strength, making them ideal for construction, cold storage, and industrial applications.
Derived from recycled PET (terephthalate-based) or phthalic anhydride.
Advantages:
High rigidity & compressive strength
Excellent fire resistance (low flammability)
Good thermal stability (for PIR foams)
Applications:
Roofing & wall insulation panels
Fire-rated construction materials
Derived from adipic acid, succinic acid, or other aliphatic diacids.
Advantages:
Better flexibility & impact resistance
Lower viscosity (easier processing)
Applications:
Flexible-faced sandwich panels
Specialty insulation foams
| Property | Polyester Polyol Foam | Polyether Polyol Foam |
|---|---|---|
| Thermal Stability | ⭐⭐⭐⭐⭐ (better for PIR) | ⭐⭐⭐ |
| Fire Resistance | ⭐⭐⭐⭐ (self-extinguishing) | ⭐⭐ |
| Compressive Strength | ⭐⭐⭐⭐ | ⭐⭐⭐ |
| Adhesion to Metal Facings | ⭐⭐⭐⭐ | ⭐⭐⭐⭐ |
| Processability | ⭐⭐⭐ (higher viscosity) | ⭐⭐⭐⭐⭐ |
| Component | Function | Example |
|---|---|---|
| Polyester Polyol | Base resin | Aromatic PET-based polyol |
| Polymeric MDI | Isocyanate (NCO) component | PMDI (30% NCO content) |
| Blowing Agent | Foam expansion | Cyclopentane, HFOs |
| Catalyst | Reaction control | Piperazine, Potassium Octoate (PIR) |
| Surfactant | Cell stabilizer | Silicone-based (e.g., Tegostab) |
| Flame Retardant | Fire resistance | TCPP, Aluminum Trihydrate |
Mixing – Polyester polyol, catalysts, and additives are blended.
Reaction with MDI – High-pressure dispensing onto metal facings (steel/aluminum).
Foaming & Curing – Expansion between facings under controlled temperature.
Pressing & Cutting – Panels are pressed for uniform thickness and strength.
✔ Higher thermal stability (better for PIR foams).
✔ Superior fire resistance (lower smoke density).
✔ Stronger mechanical properties (compressive strength).
✔ Eco-friendly option (can use recycled PET).
❌ Disadvantages:
Higher viscosity (harder processing).
More expensive than polyether polyols.
Building & Construction (PIR panels for roofs/walls)
Cold Storage & Refrigeration (freezer panels)
Industrial Insulation (HVAC, duct panels)
Transportation (refrigerated truck bodies)
Polyester polyols are ideal for high-performance rigid PU/PIR foams in sandwich panels, offering better fire resistance, thermal stability, and mechanical strength than polyether polyols. They are widely used in construction, cold storage, and industrial insulation.
