Description
Sikaflex®-221 is a Multi-purpose adhesive sealant with a wide adhesion range.
Sikaflex®-221 is a multi-purpose 1-component polyurethane adhesive / sealant that bonds well to a wide variety of substrates like metals, metal primers and paint coatings (2-component systems), ceramic materials and plastics.
It is suitable for making permanent elastic seals.
Sikaflex®-221 can be painted after formation of a skin. If the paint requires a baking process, best performance is achieved by allowing the sealant to fully cure first. 1C-PUR and 2C-acrylic based paints are usually suitable. All paints have to be tested by carrying preliminary trials under manufacturing conditions.
The elasticity of paints is usually lower than that of sealants.
This could lead to cracking of the paint in the joint area.
Application
Sikaflex®-221 can be processed between 5 °C and 40 °C but changes in reactivity and application properties have to be considered. The optimum temperature for substrate and sealant is between 15 °C and 25 °C.
Sikaflex®-221 can be processed with hand, pneumatic or electric driven piston guns as well as pump equipment.
For advice on selecting and setting up a suitable pump system, contact the System Engineering Department of Sika Industry.
