Pecora Dynaflex SC is a unique one part, non-sag, tamper resistant elastomeric STPU (silyl-terminated polyurethane) joint sealant with many of the strengths of two-component security sealants but with the user-friendly ease-of-application properties of a one-component sealant. Dynaflex SC is designed to achieve high tensile and tear strengths, abrasion resistance and an average ultimate hardness of at least 55, yet still withstand 25% total joint movement. As a result, this rugged but flexible sealant is ideally suited
for use in institutional and correctional complex security installations but
performs equally well in other public buildings and facilities where ordinary
sealants are easily damaged or torn out by idle tampering and acts of vandalism.
Security caulking requires exceptional adhesion, particularly in
containment areas like inmate cells, etc. Since Dynaflex SC’s higher hardness puts extra stress on the bond line, P-75 primer should always be used on porous substrates to obtain this superior adhesion. Steel, aluminum, polycarbonate, and glass should be primed with P-100.When applying Pecora Dynaflex SC over block that has been sealed with a block filler, priming may
be necessary. A field test should be conducted to confirm satisfactory adhesion. Contact Technical Services for other recommendations as to priming or other surface treatment.
Backer rod cushions the sealant, controls the depth and allows it to
be applied under pressure. For the firmer support recommended for security sealing, use a closed-cell polyethylene backer rod that will compress 25% when inserted into the joint. In joints too shallow for backer rod, use a
polyethylene bond-breaker tape to prevent three-sided adhesion.
Joints should be masked to ensure a neat appearance. Sealants should
be applied in a continuous fashion using standard caulking equipment. Fill the joint completely.
Tool immediately to assure full adhesion. Tooling without a slicking agent is
preferred but if conditions require one, mineral spirits is recommended.
Immediately remove all excess sealant and smears adjacent to joints with
mineral spirits. Also use mineral spirits for removing uncured sealant from equipment. Remove cured sealant by scraping, sandpapering, etc. (Caution: mineral spirits is flammable and toxic. Observe manufacturer’s precautions.)