METHOD OF STORING AN ISOCYANATE-REACTIVE COMPONENT

1 .- 3 . (canceled)

4 . A stably storable isocyanate-reactive component for preparing a polyurethane composite, comprising:

B1) an organic polyol having a functionality of from 1.7 to 6 and a hydroxyl number of from 28 to 2000 mg KOH/g;

B2) from 0.5 to 20 wt %, based on the total weight of the isocyanate-reactive component, of at least one molecular sieve; and

B3) from 0.2 to 5 wt %, based on the total weight of the isocyanate-reactive component, of at least one pentanedione.

5 . The isocyanate-reactive component according to claim 4 , wherein the isocyanate-reactive component further comprises B4) one or more compounds having the structure of formula (I)

wherein R 1 is hydrogen, methyl or ethyl; R 2 is selected from an alkylene having 2 to 6 carbon atoms, 2,2-di(4-phenylene)-propane, 1,4-di(methylene)-benzene, 1,3-di(methylene)-benzene, and 1,2-di(methylene)-benzene; n is an integer selected from 1 to 6; and component C, a radical initiator.

6 . The isocyanate-reactive component according to claim 5 , wherein B4) is present in an amount of from 10 to 65 wt %, based on the total weight of the isocyanate-reactive component.

7 . A method of preparing a polyurethane composite comprising reacting a polyurethane reaction system comprising:

component A, one or more polyisocyanates; and

component B, comprising:

B1) an organic polyol having a functionality of from 1.7 to 6 and a hydroxyl number of from 28 to 2000 mg KOH/g;

B2) from 0.5 to 20 wt %, based on the total weight of component B, of at least one molecular sieve; and

B3) from 0.2 to 5 wt %, based on the total weight of component B, of at least one pentanedione.

8 . The method of preparing a polyurethane composite according to claim 7 , wherein the polyurethane composite is prepared by a pultrusion forming process, a winding forming process, a hand lay-up forming process, a spray forming process, or a combination thereof.

9 . A polyurethane composite obtained from a polyurethane reaction system comprising:

component A, comprising one or more polyisocyanates; and

component B, comprising:

B1) an organic polyol having a functionality of from 1.7 to 6 and a hydroxyl number of from 28 to 2000 mg KOH/g;

B2) from 0.5 to 20 wt %, based on the total weight of component B, of at least one molecular sieve; and

B3) from 0.2 to 5 wt %, based on the total weight of component B, of at least one pentanedione.

10 . The polyurethane composite according to claim 9 , wherein the component B further comprises B4) one or more compounds having the structure of formula (I)

wherein R 1 is hydrogen, methyl or ethyl; R 2 is an alkylene having 2 to 6 carbon atoms, 2,2-di(4-phenylene)-propane, 1,4-di(methylene)-benzene, 1,3-di(methylene)-benzene, or 1,2-di(methylene)-benzene; n is an integer from 1 to 6; and component C, a radical initiator.

11 . The polyurethane composite according to claim 10 , wherein B4) is present in an amount of from 4.6 to 33 wt %, based on the total weight of the polyurethane reaction system.

12 . The polyurethane composite according to claim 9 , wherein the isocyanate comprises toluene diisocyanate, diphenylmethane diisocyanate, polyphenylmethane polyisocyanate, 1,5-naphthalene diisocyanate, hexamethylene diisocyanate, methylcyclohexyl diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, isophorone diisocyanate, p-phenylene diisocyanate, p-xylylene diisocyanate, tetramethyldimethylene diisocyanate, a multimer of any of the foregoing, a prepolymer of any of the foregoing, or a combination thereof.

13 . The polyurethane composite according to claim 9 , wherein the polyurethane reaction system has a gel time of from 10 to 90 minutes at room temperature.

14 . The polyurethane composite according to claim 9 , wherein the polyurethane composite is prepared by a pultrusion forming process, a winding forming process, a hand lay-up forming process, a spray forming process, or a combination thereof.

15 . The polyurethane composite according to claim 9 , wherein the polyurethane reaction system further comprises from 5 to 95 wt %, based on the total weight of the polyurethane composite, of a reinforcing material.

16 . The polyurethane composite according to claim 15 , wherein the reinforcing material comprises a fiber reinforced material, carbon nanotubes, hard particles, or a combination thereof.

17 . The polyurethane composite according to claim 16 , wherein the fiber reinforced material comprises glass fiber, carbon fiber, polyester fiber, natural fiber, aramid fiber, nylon fiber, basalt fiber, boron fiber, silicon carbide fiber, asbestos fiber, whisker, metal fiber, or a combination thereof.

18 .- 19 . (canceled)

20 . A method of improving storage stability of an isocyanate-reactive component for preparing a polyurethane composite, the isocyanate-reactive component comprising:

B1) an organic polyol having a functionality of from 1.7 to 6 and a hydroxyl number of from 28 to 2000 mg KOH/g; and

B2) from 0.5 to 20 wt %, based on the total weight of the isocyanate-reactive component, of at least one molecular sieve;

the method comprising including B3) pentanedione in the isocyanate-reactive component in an amount from 0.2 to 5 wt %, based on the total weight of the isocyanate-reactive component.

21 . The method according to claim 20 , wherein the isocyanate-reactive component further comprises B4) one or more compounds having the structure of formula (I)

wherein R1 is hydrogen, methyl or ethyl; R2 is an alkylene having 2 to 6 carbon atoms, 2,2-di(4-phenylene)-propane, 1,4-di(methylene)-benzene, 1,3-di(methylene)-benzene, or 1,2-di(methylene)-benzene; n is an integer from 1 to 6; and component C, a radical initiator.