A very important step for proper polyol selection is to determine the key properties for a given application and the environment in which the parts are required to perform. Urethane parts, for example, are used for their toughness, versatility, and durability. It's critically important to ensure that the initial properties will not significantly deteriorate over time, due to adverse environmental exposure. Selecting the best polyol for a specific formula can be the difference between making a high-quality product or one that's low performance.
Common examples of negative impacts the environment can have on urethane parts, which can accelerate their deterioration, include hydrolysis of ester-based urethane in hot and humid conditions, as well as the loss of properties that ether-based materials normally exhibit when exposed to either a hot environment or to direct sunlight.