A Proven Blowing Agent Solution for PU Panels, Refrigeration Foam, and System Houses
In the polyurethane insulation industry, the blowing agent directly determines foam density, cell structure, and long-term thermal performance. A high-purity Cyclopentane–Isopentane blend remains one of the most widely adopted options in rigid PU foam due to its stable vapor-pressure profile, strong nucleation behavior, and excellent compatibility with modern PU formulations.
This case study illustrates how an insulation panel manufacturer significantly improved foam consistency and energy-efficiency performance by adopting a 67%–73% Cyclopentane / 27%–33% Isopentane blowing agent with ultra-low impurities.
Why Manufacturers Choose Cyclopentane for PU Foam
Cyclopentane continues to be the preferred hydrocarbon blowing agent for rigid polyurethane foam because it delivers:
- Excellent insulation performance
- Stable vapor pressure during foaming
- Predictable expansion behavior
- Improved foam cell uniformity
- A practical, environmentally preferable alternative to HFCs
When blended with Isopentane, the blowing agent becomes even more versatile, allowing precise control in both continuous and discontinuous PU foam systems.
Product Specifications
The blowing agent used in this case consisted of the following parameters:
- Cyclopentane: 67–73%
- Isopentane: 27–33%
- Sulfur: ≤5 mg/kg
- Water: ≤50 mg/kg
- C1–C4 Components: ≤1.5 wt%
- C6+ Components: ≤1.5 wt%
- Benzene: ≤0.01 wt%
- Density: Measured per batch
This controlled composition ensures stable foaming behavior, consistent reactivity, and high-quality PU rigid foam output.
Case Study: PU Rigid Foam for Insulation Panels
Background
A major insulation panel manufacturer required a more consistent blowing agent to enhance foam-cell quality, improve thermal insulation value, and stabilize production performance across multiple shifts.
Problems Identified
- Non-uniform foam cell distribution
- Higher corrosion risk due to sulfur and water impurities
- Irregular expansion and slower curing consistency
- Strict benzene requirements for export markets
Solution: High-Purity Cyclopentane–Isopentane Blend
1. Improved Foam Cell Structure
The balanced vapor-pressure curve produced finer and more uniform foam cells, directly improving insulation performance and reducing thermal conductivity.
2. Increased R-Value and Energy Efficiency
Consistent foam density enhanced overall R-value, benefiting both refrigeration equipment and construction-grade insulation panels.
3. Reduced Equipment Maintenance
Ultra-low sulfur and water levels helped minimize corrosion in foaming equipment, reducing downtime and extending equipment life cycles.
4. Enhanced Production Predictability
Low levels of C1–C4 and C6+ components ensured smoother, more stable foam reactions and improved reproducibility between batches.
5. Compliance with Global Standards
Benzene ≤0.01 wt% supported stringent requirements from international building and refrigeration markets, including Europe and the Middle East.
Application Across PU Systems
This Cyclopentane–Isopentane blend is widely suitable for:
- Continuous PU sandwich panel lines
- Discontinuous PU panel systems
- PU spray foam
- PU block foam
Its stable evaporation profile makes it compatible with a wide range of rigid foam formulations.
Who Uses High-Purity Cyclopentane–Isopentane?
- PU insulation board manufacturers
- Refrigerator and freezer foam producers
- Cold-chain equipment factories
- PU foam system houses
- Industrial insulation panel manufacturers
These sectors rely on blowing agents with tight impurity control and predictable vapor-pressure behavior.
FAQ
Q1: What is the most common blowing agent for rigid PU foam?
Cyclopentane or a Cyclopentane–Isopentane blend is widely used due to strong insulation performance and stable foaming characteristics.
Q2: Why must blowing agents have low sulfur and water?
Sulfur and water can corrode equipment, disrupt catalyst systems, and negatively impact foam structure and curing.
Q3: Does a Cyclopentane–Isopentane blend improve foam uniformity?
Yes. The balanced vapor-pressure curve contributes to consistent foam-cell formation.
Q4: What benzene level is acceptable for blowing agents in insulation applications?
Most export markets require benzene ≤0.01 wt% for PU foam blowing agents.
Q5: Is this blend suitable for continuous PU panel lines?
Yes. Its stable evaporation behavior makes it ideal for continuous manufacturing systems.
Conclusion
This case study demonstrates how a high-purity Cyclopentane–Isopentane blend can significantly enhance rigid PU foam performance, improve thermal efficiency, stabilize reactivity, and reduce operational risks in industrial environments.
Call to Action
If you require high-purity Cyclopentane, Isopentane, or customized hydrocarbon blends for polyurethane foam applications, detailed specifications, SDS files, and sample support are available upon request.