Thermal Conductivity & Insulating Performance of PA66 GF25

PA66 GF25 has become one of the leading thermoplastic materials for thermal-break profiles due to its highly favorable balance between structural strength and thermal insulation. With the growing demand for energy-efficient buildings, the performance of insulating materials within aluminum frames has become increasingly important. The inherently low thermal conductivity of PA66 GF25, along with its mechanical durability, makes it a reliable solution for modern façade and window designs.

1. Low Thermal Conductivity as a Core Advantage

Unreinforced nylon already has good insulating properties, but PA66 containing 25% glass fiber maintains thermal conductivity in the range of 0.25–0.30 W/m·K—significantly lower than metals such as aluminum. Although glass fibers slightly increase the thermal conductivity, the final value still remains excellent for thermal-barriers. The polymer matrix restricts heat transfer, helping to reduce heat loss and improve overall building efficiency.

2. Contribution to U-Value Optimization

In thermal-break systems, PA66 GF25 directly influences the U-value of aluminum windows and façades. By separating the interior and exterior aluminum sections, the polyamide barrier eliminates thermal bridges that would otherwise lead to energy loss. High-precision insulating bars help architects meet strict energy requirements such as Passive House standards and modern green-building certifications.

3. Environmental Stability and Performance Retention

Thermal insulation materials must withstand humidity, temperature changes, and exposure to sunlight. PA66 GF25 is engineered to maintain its insulating ability even under seasonal temperature fluctuations and varying humidity conditions. Its stability ensures long-term performance without warping, shrinking, or losing mechanical strength. This makes it suitable for both residential and commercial architectural systems.

4. Compatibility with Extrusion and Profile Geometry

The ability to extrude PA66 GF25 into complex shapes enables manufacturers to design insulating bars that enhance both structural and thermal performance. Multi-chamber geometries, surface textures, and mechanical interlocking features maximize insulation efficiency while ensuring precise installation within aluminum frames. Controlled cooling after extrusion ensures consistent thermal behavior in finished profiles.

Conclusion

PA66 GF25 combines low thermal conductivity, environmental stability, and mechanical robustness, making it ideal for advanced insulation applications. Its ability to deliver long-lasting insulation contributes to lower energy consumption, improved building comfort, and enhanced durability of aluminum systems. As energy regulations become stricter, PA66 GF25 remains one of the most reliable materials for modern thermal-break designs.