XtraBond®8500 - Modified Polyurethane Sealant

XtraBond® 8500 is a one component, medium modulus, permanently flexible, multi-purpose easy to use fast cure modified polyurethane sealant. XtraBond® 8500 is environmentally friendly and offers excellent adhesion to vinyl, sheet metal, steel, pre-painted metals, wood, glass, aluminum, plastic, common construction substrates of: window, door, siding, flashing & underlayment papers.


  • Perimeter sealing ofwindows, doors & skylights
  • Siding
  • Construction Flashing Applications
  • Sealing WaterProof Membrane
  • Industrial Applications


  • AAMA Certified
  • Environmentally friendly
  • No Solvents
  • Fast Cure at a wide range of temperatures
  • Aggressive Adhesion to common construction substrates
  • Compatible with SBS Flashing
  • Very Low VOC’s


Exceeds the requirements of ASTM C 920, Type S, Grade NS, Class 25, Use NT, M, G and A

• Federal Specification TT-S-00230C, Type II, Class A
• CAN/CGSB-19 13-M87
• AAMA 808.3-92 Exterior Perimeter Sealing.

Technical Specs

Skin Time Less than 20 minutes @ 77 degF/ 50% RH
Tack Free Time Less than 1 hour @ 77 degF / 50% RH
Cure Rate 1/4” Bead / 24 Hrs
VOC 7 g/L (0.0751 lb/gal)
Elongation @ Break 450%
Hardness (shore A) 35 +- 5
Movement Capability 25%
UV Rating No discoloration or change in appearance after 2500 hours of UV
Lap Shear 325 psi
Tensile Strength 250 psi
Staining None
Low Temp.  Flexibility Retained to -90 degrees F
High Temp. Flexibility Up to 425 degress F for short periods
Sag None




The XB8500 is available for the following industries


This product is available in the following configurations:

  • 10.1 fl oz cartridges: Fixed-Tip Nozzles
  • 20 oz fl oz. Sausages

Limited Lifetime Warranty

This product is guaranteed to give satisfactory performance if applied in accordance with the label directions. Liability to Premier Industrial Supply, Inc. (Premier) is limited to a full refund of the purchase price or product replacement if product is proven defective. Premier shall not be liable for loss or damage, whether direct, consequential or incidental. There are no other warranties expressed or implied including the implied warranty of merchantability or fitness for a particular purpose.