BOSS PU 25 is low modulus one-component moisture curing Class A polyurethane sealant. It cures into a flexible, durable and weather resistant elastomeric sealant that has very good adhesion to most construction and industrial materials. It can accommodate cyclic joint movement of 50% (+/-25%) of the joint width. is recommended for use in moving expansion joints between precast concrete panels, brick and block work, granite, marble and sandstone, aluminum windows, FRP, metal, coated metal curtain walls and seams on
timber, aluminum, U-PVC joinery, etc,.
BOSS®PU 25 can be used for bonding or sealing lap seams on trucks, bus, trains, trailers, roofs vans,RV’s specialty vehicles and constructions panels.
Primerless adhesion to most
Cures to a tough, flexible rubber
HOW TO USE
For successful bonding and sealing, substrates must be free of excess dust, dirt, moisture and oils. Clean substrate with a degreasing solvent. In some instances, slight
abrasion of the substrate surface may be necessary to ensure proper adhesion.Maximum joint width should not exceed 1-1/4” and should be no deeper than 3/8”. For greater
depth use a foam backer rod to within 3/8” of desired surface level. Sealant should be applied by “pushing” the bead ahead of nozzle forcing the sealant into the joint ensuring
adequate contact with all joint surfaces. Tooling of material needs to be completed within 40 minutes of application. Excess sealant should be removed with a clean dry
cloth within the tooling time while still uncured.
If joint has been masked, masking material should be removed immediately after sealant application as cured sealant is difficult to remove.
Polyurethane Adhesive/Sealant is available in 600 ml Sausage, 4.5 gallon pails and 55 gallon drums. Other sizes available upon request.
When stored in original unopened container at or below 80°F, Polyurethane Adhesive/Sealant has a shelf life of 12 months from date of manufacture. Containers should
always be kept sealed when not in use.