Linear polyurethane elastomer compositions based on mixed polycarbonate and polyether polyols
AssigneeReeves Brothers, Inc.
InventorsBert A. Ross, John R. Damewood
Life of this patent
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Abstract
New linear polyurethane elastomers have been developed by combining a polycarbonate polyol, a polyether polyol, at least two extenders, and a solid diisocyanate compound. Preferably, the diisocyanate compound is modified by reaction with one of the extenders to form a modified diisocyanate component which is a liquid at room temperature prior to reaction with the polyols and other extender. These new elastomers possess a unique combination of hydrolytic stability, toughness, flexibility, and relatively low temperature processability.
Claims27
A linear thermoplastic polyurethane elastomer composition comprising:
- a polycarbonate polyol;
- a polyether polyol;
- a diisocyanate compound;
- a first extender component;
- and
- a second extender component;
- wherein the diisocyanate compound is initially reacted with one of the extender components in a molar ratio of above 2:1 so as to form a modified diisocyanate component having a functionality of about 2 prior to reaction with the other components to provide relatively low temperature processing properties to the composition, whereas the polyol component provides superior hydrolytic stability and low temperature flexibility properties to the composition.
The composition of claim 3 wherein the first extender component comprises a diol.
A linear thermoplastic polyurethane elastomer composition comprising:
- a mixed polyol component comprising a polycarbonate polyol in an amount sufficient to impart hydrolytic stability to the composition and a polyether polyol in an amount sufficient to improve the low temperature impact properties to the composition;
- a diisocyanate compound;
- a first extender component;
- and
- a second extender component;
- wherein each of the extender components is a polyol or amine compound having a molecular weight of less than about 500, and the diisocyanate compound is modified by reaction with one of the extender components in a molar ratio of above 2:1 so as to form a modified diisocyanate component having a functionality of about 2 prior to reaction with the remaining components, said extender components providing relatively low temperature processing properties to the composition.
A linear thermoplastic polyurethane elastomer composition comprising:
- a mixed polyol component comprising a polycarbonate polyol in an amount sufficient to impart hydrolytic stability to the composition and a polyether polyol in an amount sufficient to improve the low temperature impact properties of the composition;
- a diisocyanate compound comprising 4,4,diphenylmethane diisocyanate;
- a first extender component;
- and
- a second extender component;
- wherein each extender component is a polyol or amine compound having a molecular weight of less than about 500, and the diisocyanate compound is modified by reaction with one of the extender components in a molar ratio of above 2:1 so as to form a modified diisocyanate component having a functionality of about 2 and an NCO content of between about 14 and 33% prior to reaction with the remaining components, said extender components providing relatively low temperature processing properties to the composition.
A linear thermoplastic polyurethane composition consisting essentially of:
- a mixed polyol component comprising a polycarbonate polyol in an amount sufficient to impart hydrolytic stability to the composition and a polyether polyol in an amount sufficient to improve the low temperature impact properties of the composition, the polyether polyol and polycarbonate polyol being present in a relative amount of between 2:1 to 1:8;
- a diisocyanate compound comprising 4,4'- diphenylmethane diisocyanate;
- a first extender component;
- and
- a second extender component;
- wherein each extender is a polyol or amine compound having a molecular weight of less than about 500, and the diisocyanate compound is modified by reaction with the first extender component in a molar ratio of above 2:1 so as to form a modified diisocyanate compound having a functionality of about 2 and a NCO content of between about 14 and 33% prior to the sequential reaction of the modified diisocyanate first with the polyol and then with second extender component, said extender components providing relatively low temperature processing properties to the composition.
Dependencies are inferred from the claim text.