| Quantity: | |
|---|---|
XF-2412; XF-2020; XF-235; XF-2402N; XF-2002; XF-2007; XF-235P;
Rigid foam polyester polyols for PIR (Polyisocyanurate) panels are mainly used to produce high-performance thermal insulation boards and sandwich panels for cold storage, industrial buildings, roofing, and wall insulation systems. These polyester polyols are typically aromatic polyester polyols with high hydroxyl values and are reacted with polymeric MDI at a high isocyanate index to form PIR structures.
| Property | Typical Range |
|---|---|
| Hydroxyl Value | 200–450 mg KOH/g |
| Functionality | 2.0–3.5 |
| Viscosity | 2,000–10,000 cps @ 25°C |
| Acid Value | < 2 mg KOH/g |
| Water Content | < 0.2% |
| Aromatic Content | High |
Fire resistance
Char formation
Dimensional stability
Compressive strength
Thermal insulation performance
These are important for PIR sandwich panels used in construction and refrigeration.
Used in:
Cold rooms
Industrial wall panels
Roofing panels
Clean rooms
Benefits:
Excellent adhesion to metal facings
Good foam flowability
Uniform cell structure
Low thermal conductivity (low lambda)
Suitable for:
Custom insulated panels
Refrigerated truck panels
Pipe insulation sections
PIR foams provide:
Better thermal efficiency
Higher dimensional stability at low temperature
Improved moisture resistance
PIR chemistry forms isocyanurate rings, improving:
Flame resistance
Smoke suppression
Thermal stability up to ~140–200°C depending on formulation
Phthalic anhydride based polyester polyols
PET recycled aromatic polyester polyols
Terephthalic acid based polyester polyols
Usually:
Polymeric MDI (pMDI)
Common options:
Cyclopentane
n-Pentane / Iso-pentane blends
HFO blowing agents
HCFC-141b (being phased out globally)
Common catalysts include:
DMCHA
TEDA
DMAEE
Stannous Octoate
Catalyst selection strongly affects PIR trimerization, cure speed, adhesion, and panel dimensional stability.
Example rigid PIR panel formulation:
| Component | pbw |
|---|---|
| Aromatic Polyester Polyol | 100 |
| Cyclopentane | 10–18 |
| Water | 0.5–1.5 |
| Silicone Surfactant | 1.5–2.5 |
| Amine Catalysts | 1.5–4.0 |
| Potassium Acetate PIR Catalyst | 2–5 |
| Flame Retardant | 10–25 |
| Polymeric MDI | Index 220–350 |
Higher PIR index improves:
Fire performance
Heat resistance
Char strength
But excessive index may increase brittleness.
Compared with polyether systems:
| Feature | Polyester Polyol PIR |
|---|---|
| Fire resistance | Better |
| Compressive strength | Higher |
| Adhesion to metal | Better |
| Dimensional stability | Better |
| Hydrolysis resistance | Moderate |
| Processing viscosity | Higher |
Examples include:
Stepan Company STEPANPOL® series
Dow Inc. VORATHERM™ FF series
Huntsman Corporation DALTOPIR® systems
Synthesia Technology aromatic polyester polyols
Esterpol rigid foam polyester polyols
PIR panels are commonly produced by:
Continuous double-belt lamination lines
High-pressure foaming machines
Pentane-compatible systems
Critical process parameters:
Cream time
Gel time
Tack-free time
Core density
Panel adhesion
Cell uniformity
Parameters
| Product Model | Hydroxyl value (mgKOH/g) | Acid Value (mgKOH/g) | Moisture (%) | Viscosity (CPS 25℃) |
| XF-2412 | 260±10 | ≤1.5 | ≤0.1 | 8000+1500 |
| XF-2020 | 200±10 | ≤1.5 | ≤0.1 | 7000±1000 |
| XF-235 | 230-245 | ≤2.0 | ≤0.15 | 10500±1500 |
| XF-2002 | 195±5 | ≤1.0 | ≤0.1 | 10000-30000 |
| XF-2007 | 200±10 | ≤2.0 | ≤0.1 | 15000±3000 |
| XF-235P | 235±15 | ≤2.0 | ≤0.15 | ＜3500 |
| XF-2402N | 240±10 | ≤1.5 | ≤0.1 | 8000±1500 |
