Dual-Component Polyurethane Systems
In solvent free dual-component polyurethane systems, foam and bubbles form when the isocyanate hardener reacts with water to produce carbon dioxide:
R-N=C=O + H20 → R-NH2 + CO2
polyisocyanate water amine carbon dioxide
These problems can be avoided through the use of a SYLOSIV® molecular sieve. It adsorbs the moisture within a few hours, which means that undesirable reactions can no longer take place.
For this application, Grace Davison offers various molecular sieve powders as well as a castor oil based molecular sieve paste for easier handling.