Siliporite® Molecular sieves for insulated glass
Modern insulating glass units (IGUs) achieve their performance through the combined action of advanced glass coatings, insulating gases, spacer technologies, and effective moisture control. Molecular sieves are one of the key components designed for this purpose and are required in insulating glass units to absorb residual moisture and prevent condensation inside the glazing. Their ability to maintain a dry sealed cavity contributes to the long-term reliability, transparency, and energy efficiency of double and triple glazing.
- Worldwide
Related products
How Molecular Sieves Work in Insulating Glass Units (IGUs)
Molecular sieves technology consists in highly engineered synthetic zeolites with a uniform network of microscopic pores that selectively adsorb water molecules. When incorporated into double or triple glazing units, they continuously remove residual moisture trapped inside the sealed airspace and capture any water vapor that may enter over the lifetime of the window.
Thanks to their strong affinity for water and their ability to adsorb moisture even at very low humidity levels, molecular sieves prevent condensation and fogging between the glass panels. Unlike conventional desiccants, 3Å molecular sieves selectively adsorb water without significantly interacting with insulating gases such as argon, krypton or nitrogen, helping maintain the thermal performance of the glazing unit.
By keeping the cavity dry for decades, molecular sieves protect coatings applied to the glass, preserve transparency, and contribute to the long-term energy efficiency and durability of insulating glass windows.
Rigid spacer vs. flexible Warm edge spacer technologies
Two main spacer technologies are used in modern insulating glass units: rigid spacers and flexible warm edge spacers. Traditional rigid spacers are typically made from aluminum or steel and are filled with molecular sieve beads.
They offer excellent mechanical strength and proven long-term durability but create a thermal bridge at the edge of the glass, which can increase heat loss and reduce the overall energy efficiency of the window.
Flexible Warm edge spacers, on the other hand, are made from low-thermal conductivity polymeric or composite materials that contain molecular sieve powder dispersed within the spacer structure.
By significantly reducing thermal conductivity at the glass edge, flexible warm edge technologies minimize heat transfer, helps maintain more consistent interior temperatures, lowers condensation risk around the frame, and enhance the window's overall thermal performance.
In addition, the flexibility of polymer-based spacer systems enables greater freedom in window design, making it easier to manufacture complex shapes and innovative glazing configurations. These technologies can also simplify production processes by reducing manual handling and labor requirements during assembly.
As energy-efficiency requirements become more demanding, flexible warm edge spacers are increasingly preferred for high-performance residential and commercial glazing, while rigid spacers remain widely used where robustness and cost efficiency are priorities.
Key products
| Product | Application | Pore size |
| NK30AP | Polymer Warm edge technology | 3A powder |
| NK30AP SC | Polymer Warm edge technology | 3A powder |
| NK30 BEADS | Rigid spacers | 3A beads |
Molecular Sieves for sustainable construction
Molecular sieves help improve the sustainability and long-term performance of insulating glass units by keeping the sealed cavity dry throughout the window's lifetime.
Key sustainability benefits
- Improves the energy efficiency of buildings by preserving the insulating performance of double and triple glazing
- Prevents condensation and fogging, ensuring long-lasting transparency and comfort
- Protects sealants, coatings, and spacer systems from moisture-related degradation
- Extends the service life of windows, reducing maintenance and replacement needs
- Supports lower energy consumption and reduced carbon emissions from buildings