XILFLEX 2-Part Insulating Glass


XILFLEX® 2P-IG is a two-part silicone sealant that will cure to a high-modulus rubber suitable for secondary sealing in insulating glass units. It offers variable working speed through different combination ratio of the base and catalyst components, and provides fast deep cure to facilitate high speed production needs.


  • Excellent Adhesion to many conventional spacer materials without primer.
  • Fast Cure – enables shipping of fabricated insulating glass units within hours of completion without silicone transfer and glass shifting.
  • Low Pumping Viscosity – allows void free filling coupled with high throughput and low strain on pumping equipment.
  • Durability – silicone sealant naturally shows excellent long term resistance to natural weathering, including extreme temperatures, UV radiation, rain and other atmospheric elements.


  • Part A (White) – 190 L (284 kg) in 205 L steel drum
  • Part B (Black) – 19 L (19.5 kg) in 25 L plastic pail.


  • Recommended mixing ratio is 10-12:1 (by volume) or 14.8-17.8:1 (by weight).
  • Prior to production, hand-mix desired ratio of the base and catalyst to check that desired snap time is achieved. Check also that curing is achieved within reasonable time. This will validate the material performance separately from production equipment.
  • This procedure should be done daily to account for daily changes in atmospheric condition.


Part A - Base Part B – Catalyst
Form Viscous Paste Viscous Paste
Color White Black
Specific Gravity 1.48 1.01
Shelf Life 18 months 12 months
Mixed Compound
Color Black
Recommended Mixing Ratio By volume By weight
10 : 1 14.65 : 1
11 : 1 16.28 : 1
12 : 1 17.58 : 1
Specific Gravity 1.44 Mixed at 10:1 ratio by volume
Snap Time 20 – 75 minutes Depends on mixing ratio Tack-Free Time 2x snap time and ambient condition
Tack-Free Time 2x snap time Depends on mixing ratio Tack-Free Time 2x snap time and ambient condition
Hardness (Shore A) 44 ASTM D2240
Ultimate Tensile Strength 1.04 MPa ASTM D412
Elongation at Break 150% ASTM D412
  • Clean all surfaces of all dirt, oils and any foreign matters using IPA, MEK, toluene or other suitable solvents. Apply the sealant within 2 hours after cleaning.
  • Hand mixing of the base and catalyst component should be done only when performing preliminary testing.
  • Perform butterfly test to ensure proper mixing. The material should show solid homogenous black color, free of any swirling or marbling of colors. If incomplete mixing is observed, cease operation and adjust equipment until proper mixing is attained.


  • Not to be used as the primary seal insulating glass units.
  • Do not expose to acetic acid evolved by adjacent sealants.
  • Not recommended for water immersion applications.


  • Because the catalyst can react with atmospheric air, please do not leave it exposed for prolonged period of time.
  • During equipment shutdown, flush dispensing and mixing line with uncatalyzed base to minimize sealant buildup.
  • Material Safety Data Sheets (MSDS) are available upon request.