Bostik STR220A is a good compromise between an adhesive and a sealant. STR220A is based on Silyl Modified Polymer (SMP) and is suitable for making elastic constructive joints and elastic sealings.
Bostik STR220A is a high quality product based on Silyl Modified Polymer (SMP), especially developed for bonding and sealing in bus, caravan, and trailer construction. In general, STR220A adheres well without primer on clean, dry, dust and grease free substrates of aluminium, stainless steel, galvanized steel, zinc, copper, brass, powder coated metal, most lacquered metal surfaces, glass, PVC, polyester (GRP), painted and lacquered wood, etc. No adhesion on untreated polyethylene, polypropylene and teflon. In case of high adhesion demands the use of Prep M is recommended. Prep M degreases and prepares the surface of the substrate in one step. On plain, untreated wooden surfaces and other porous substrates Prep P is recommended. For more details concerning Prep M and Prep P consult the Technical Data Sheets. For not mentioned substrates and additional information consult Bostik.
METHOD OF USE
STR220A can easily be extruded with a hand or air pressure gun at temperatures between 41°F to 95°F (+5°C and +35°C). In sealing applications, STR220A should be tooled or smoothened within 10 minutes (at 70 °F (20°C)/50%R.H.) with a spatula or putty knife, occasionally moistened with a soap solution. Avoid soap solution penetrating between joint sides and sealant, because this will create loss of adhesion. In bonding applications the substrates have to be assembled within 20 minutes (at 70 °F (20°C)/50%R.H.) after applying STR220A. In general, an adhesive thickness of 2 mm