Reactive wax-containing moisture curable hot melt composition
AssigneeMinnesota Mining and Manufacturing Company
InventorsCharles W. Stobbie, IV, John C. Tangen
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Abstract
A moisture curable hot melt composition comprises: (a) a first isocyanate-terminated polyurethane prepolymer that is the reaction product of a crystalline polyester polyol and a polyisocyanate; (b) a crystalline, reactive wax; and (c) optionally, a second isocyanate-terminated polyurethane prepolymer that is the reaction product of a polyisocyanate and a hydroxy-functional polymer that is different than the crystalline polyester polyol.
Claims28
A moisture curable hot melt composition comprising:
- (a) a first isocyanate-terminated polyurethane prepolymer that is the reaction product of a crystalline polyester polyol and a polyisocyanate;
- (b) a crystalline, reactive wax;
- and
- (c) optionally, a second isocyanate-terminated polyurethane prepolymer that is the reaction product of a polyisocyanate and a hydroxy-functional polymer that is different than the crystalline polyester polyol.
A moisture curable hot melt composition comprising:
- (a) a first isocyanate-terminated polyurethane prepolymer that is the reaction product of:
- (i) a crystalline polyester diol obtained by reacting a diol having the structure HO--(CH.sub.2).sub.x --OH wherein x=2 to 8 and a diacid having the structure HOOC--(CH.sub.2).sub.y --COOH wherein y=1 to 12, and
- (ii) diphenylmethane diisocyanate;
- (b) 0.01 to 5% by weight, based on the total weight of the hot melt composition, of a crystalline, reactive wax that includes a hydroxyl or a carboxyl group;
- and
- (c) a second isocyanate-terminated polyurethane prepolymer that is the reaction product of a polyether polyol and diphenylmethane diisocyanate.
A method of reducing the set time of a moisture curable hot melt composition that includes a polyurethane prepolymer that comprises the reaction product of a polyisocyanate and a crystalline polyester polyol, the method comprising the step of adding to the hot melt composition an effective amount of a crystalline, reactive wax.
Dependencies are inferred from the claim text.