Butyl Sealant for Insulating Glass Units
Butyl sealant is a single-component primary sealant based on polyisobutylene (PIB), specifically designed for use with aluminum spacer bars as the first sealing barrier in the production of insulating glass units (IGUs).

Its primary function is to provide an exceptionally effective barrier against moisture and gas transmission, ensuring the long-term performance and energy efficiency of the insulating glass unit.

Characteristics
Color: Black
Composition: Polyisobutylene (PIB) polymer
Bonding Surfaces: Glass, aluminum, steel, and composite materials
UV and Aging Resistance: Excellent
Moisture and Gas Permeability: Extremely low
Operating Temperature Range: -45°C to +120°C
Temperature Flexibility: Maintains elasticity across a wide temperature range; does not flow at high temperatures and does not harden or crack at temperatures as low as -45°C
Moisture Vapor Transmission Rate: Less than 0.2 g/m² per 24 hours through a 0.5 mm membrane film
Extrusion Temperature: 100°C – 120°C at 180–200 bar pressure
Maximum Heating Temperature: Do not heat above 130°C
Shelf Life: 12 months when stored in dry conditions below 27°C
Advantages
Easy to apply
Enables the production of highly efficient insulating glass units with long service life
Remains flexible at low temperatures
Excellent UV resistance
Superior corner sealing performance
Outstanding adhesion to glass, aluminum, galvanized steel, and composite materials
Easily applied using standard butyl extrusion equipment
Produces a smooth, continuous bead at a predefined minimum thickness
Extremely low moisture and gas permeability
Applications
Butyl sealant is used as the primary seal (first barrier) in insulating glass units, where it provides the essential moisture and gas-tight seal required for long-term thermal insulation performance. Combined with a secondary sealant, it forms a highly durable sealing system that meets the demanding requirements of modern architectural glazing and energy-efficient building applications.