Linear polyurethane elastomer compositions and use of modified diisocyanates for preparing same

摘要

Linear polyurethane elastomers of a polyol component, at least two extender components, and a diisocyanate compound are prepared by reacting the diisocyanate compound with one of the extender components to form a modified diisocyanate component having a functionality of about 2 prior to reacting this modified component with the other components of the elastomer. A preferred polyol component includes a mixture of a polycarbonate polyol and a polyether polyol. These new elastomers possess a unique combination of hydrolytic stability, toughners, and flexibility and can be processed at lower temperatures compared to elastomers prepared from similar compositions wherein the isocyanate compound is not modified.