Polyols are compounds with multiple hydroxyl functional groups available for organic reactions. Among the naturally occurring polyols, castor oil is one of the most prevalent. Additionally, castor oil undergoes most of the reactions that alcohols do, including one of the most industrially important ones, which is the reaction with isocyanate-functional materials to make polyurethanes.
Polyurethanes, resulting from the polyaddition of polyisocyanates and polyol compounds, are broadly used in the form of reactive one or two component systems as used in adhesives, sealing materials, durable elastomeric wheels and tires, automotive suspension bushings, electrical potting compounds, Spandex fibers, seals, gaskets, carpet underlay, hard plastic parts, decorative or protective coatings and floorings. In each of these applications, their resistance against ageing and attack by chemical substances, such as for example water, and environmental conditions are of great importance.
Currently, polybutadiene-based polyols are commonly used to produce polyurethane compounds with excellent hydrolytic stability. Unfortunately, the use of these polyols in the production of polyurethane is limited by the inherently high viscosity, limited tensile and elongation properties, and limited compatibility with other types of polyols.
Accordingly, there is a need for a polyol or polyol mixture which can be used for the production of polyurethane compounds, and has lower viscosity and provides polyurethane compounds with improved tensile and elongation properties over polyurethanes compounds derived from polybutadiene-based polyols, while maintaining excellent hydrolytic stability properties.
Almost all of today's commercially polybutadiene-based polyols are produced from petroleum. The depletion of petroleum combined with its increasing price has encouraged efforts at development of polymeric material from renewable natural resources.
Accordingly, there is a need for polyols or polyol mixtures which can be prepared from renewable natural resources, and which maintain excellent hydrolytic stability of the polyurethane compounds derived from the polyols or polyol mixtures.