The addition of moisture scavengers to polyurethane formulations produces high-quality polyurethane products. Polyurethane products are made by the reaction of isocyanates with hydroxyl groups on polyols. Because isocyanates will react with moisture to form polyamides while liberating the byproduct - carbon dioxide, these microbubbles are coated in the finished polyurethane products, thereby affecting the appearance of the products. Therefore, if a dehydrating agent is added to the formula, the reaction between isocyanate and moisture can be greatly reduced. In addition, adding dehydrating agents to coatings or adhesives minimize the reaction of isocyanates with moisture.
Johnson provides two general types of water scavengers, TEO and MSI for your options. We can assist you to choose the appropriate dehydrating agent which provides the best physical properties you request for your application.