The effects of some chemical components of polyurethane sealants on their resistance against hot water

The effect of hot-water immersion on the degradation of polyurethane sealants was reviewed. Polyurethane sealants made from a hydrophobic polyol was shown to exhibit persistent hot water resistance than those made from the commonly used polypropylene glycol diol. Compromise between adhesion, cohesion, water swelling and thermal oxidation is discussed.