Low Modulus Silicone Sealant Product description neutral-cure silicone sealant with an unusual capacity lo recover from large extensions and compressions, allowing it to compensate (or ±50% joint movement Upon curing, PSI-641 forms a durable, flexible, watertight bond to most common building materials, Including concrete, masonry, glass, ceramic, many metals, wood and most plastics. In most cases primer is not required. It is gunnable at all temperatures and has a long tooling time. Basic uses PSI-641 is Ideal for sealing expansion and control joints; perimeters of door and window frames; glazing of glass, metal and plastic; curtain wall and mullion joints, and many other types of construction joints, especially those subject to severe dynamic movement. It is virtually unaffected by long term exposure to rain, snow, sleet, ice, sunlight, ultraviolet radiation and atmospheric pollution. • Highly flexible over a wide temperature range. • Excellent weatherability, durablity and recovery after movement. • Accommodates joint movement of ±50%. Application limitations • Should not be used for structural or butt glazing, nor in expansion joints less than 1/4" in width • Should not be applied to areas that will be totally confined during cure as atmospheric moisture • Not recommended for horizontal joints subject to abrasion such as decks, walks, driveways. etc., unless properly recessed. • Not recommended for application to materials that might bleed oils or solvents. • Should not be applied to joints to be painted or surfaces with reflective or protective coatings without prior testing. • Although there are no toxic leachable materials in cured PSI-641, some of the ingredients are not included in the FDA list of acceptable materials for food contact (21 CFR 177.2600). Clear. White, Bronze. Custom colors available; minimum order 100 gallons. cartridges, 12 cartridges per carton. It is also available in 2-gallon pails, 5-gallon pails and 55-gallon drums on special order. Applicable standards PSI-641 meets the requirements of Federal Specification TT-S-001543A, Class A; Federal Specification TT-S-O0230C, Type II, Class A; ASTM C920, Type S, Grade NS, Class 25, use NT, G, A, M, O; MIL-A-46106B. Group I, Type I; Canadian Joint Design: Good construction industry joint design dictates 4 times the anticipated movement of building components be used when calculating joint width. The theoretically derived 2:1 movement factor is based on thermal movement alone and doesn't allow for variances found at the jobsite and therefore should not be used. The 4:1 design factor accommodates both thermal movement and wide variations in tolerances of construction materials, fabrication and erection often found in the field. This will also accommodate joints installed narrower than originally designed.

Joint dimension: Minimum allowable joint width and depth is 1/4" and should not exceed 1/2" deep Panels and lights of less than 100 united inches should allow a minimum width of 1/4" for the sealant bead. Larger panels and lights and those made of plastic require at least 4 times the postulated Surface preparation: Clean all joints and glazing areas by removing foreign matter and contaminants such as moisture, frost, dirt, dust, oil, grease, protective coatings and previously applied sealant or glazing compound. For expansion joint applications, install compatible backing material. Priming: PSI-641...

Health precautions • Product contains chemicals that are skin sensi- tizers and may cause severe eye injury. Avoid skin/eye contact. • Remove contact lenses before using product. Wear eye protection. After use, do not handle contact lenses until product is cleaned from fingertips, nails, and cuticles. Product can transfer to contact lenses and cause eye irrita- tion or injury For eye contact, immediately flush eyes with water for 15 minutes; seek immedi- • For skin contact, remove product from skin with dry cloth; wash skin with soap and water. • If swallowed, seek medical attention. • Product...