Process for the production of rigid and semi-rigid foams with low amounts of diisocyanate using polymer polyols characterized by high solids and a high hydroxyl number and the resultant foams

1. A rigid or semi-rigid polyurethane foam comprising the reaction product of:

(A) less than 75 pbw, based on 100 pbw of component (B), of at least one polyisocyanate; with

(B) an isocyanate-reactive component having a solids content of at least 40% by weight, an overall hydroxyl number of the liquid, non-solids portion of at least 160, and comprising:

(1) at least 50% by weight of a polymer polyol having a solids content of at least 30% by weight, in which the base polyol of the polymer polyol has a hydroxyl number of at least 70 and a functionality of 2 to 8, and

(2) no more than 50% by weight of one or more second polyols, said second polyol being different than the polymer polyol (1),

with the sum of the %'s by weight of polyols (1) and (2) totaling 100% by weight of (B);

in the presence of

(C) at least one blowing agent;

(D) at least one surfactant; and

(E) at least one catalyst.

2. The polyurethane foam of claim 1 , wherein (A) said polyisocyanate comprises greater than 50% by weight of toluene diisocyanate.

3. The foam of claim 1 , wherein (A) said polyisocyanate comprises 100% by weight of toluene diisocyanate.

4. The polyurethane foam of claim 1 , wherein (A) said polyisocyanate is present in an amount of less than 65 pbw, based on 100 pbw of component (B).

5. The polyurethane foam of claim 1 , wherein (B) said isocyanate-reactive component has a solids content of at least 45% by weight, an overall hydroxyl number of the liquid, non-solids portion of at least 180, and has a functionality of about 2 to about 8.

6. The polyurethane foam of claim 1 , wherein (B)(2) said one or more second polyols is characterized by a hydroxyl number of 10 to 2000 and as having a functionality of at least 2.

7. The polyurethane foam of claim 1 , wherein (B) said isocyanate-reactive component comprises:

(1) at least 70% by weight of a polymer polyol having a solids content of at least 40% by weight, and in which the base polyol of the polymer polyol has a hydroxyl number of 70 to 600 and a functionality of 2 to 6; and

(2) no more than 30% by weight of one or more second polyols, with the second polyol having a hydroxyl number of 15 to 1500 and a functionality of 2 to 6.

8. The polyurethane foam of claim 1 , wherein (B) said isocyanate-reactive component comprises:

(1) at least 80% by weight of a polymer polyol having a solids content of at least 50% by weight, and in which the base polyol of the polymer polyol has a hydroxyl number of 100 to 600 and a functionality of 2 to 4; and

(2) no more than 20% by weight of one or more second polyols, with the second polyol having a hydroxyl number of 20 to 1000 and a functionality of 2 to 4.

9. The polyurethane foam of claim 1 , wherein (B)(2) comprises a polymer polyol having a solids content of no more than about 80% by weight, and in which the base polyol has a hydroxyl number of from about 10 to less than 70, and a functionality of at least two.

10. The polyurethane foam of claim 1 , in which (B)(2) is selected from the group consisting of polyether polyols, chain extenders and crosslinking agents.

11. The polyurethane foam of claim 1 , wherein (C) said blowing agent is present in an amount of from 0.5 to 10 parts by weight, based on 100 parts by weight of component (B) the isocyanate-reactive component.

12. The polyurethane foam of claim 1 , wherein the base polyol of the polymer polyol used as (B)(1) has a functionality of >2.2.

13. The polyurethane foam of claim 1 , in which the density is greater than 0.7 pcf.

14. The polyurethane foam of claim 1 , in which the adjusted 50% CFD is greater than 7.0 psi.

15. The polyurethane foam of claim 1 in which the foam is a free-rise foam.

16. The polyurethane foam of claim 1 in which the foam is a molded foam.

17. A process for the production of a rigid or semi-rigid polyurethane foam comprising

(I) reacting

(A) less than 75 pbw, based on 100 pbw of component (B), of at least one polyisocyanate;

(B) an isocyanate-reactive component having a solids content of at least 40% by weight, an overall hydroxyl number of the liquid, non-solids portion of at least 160, and comprising:

(1) at least 50% by weight of a polymer polyol having a solids content of at least 30% by weight, in which the base polyol of the polymer polyol has a hydroxyl number of at least 70 and a functionality of 2 to 8, and

(2) no more than 50% by weight of one or more second polyols, said second polyol being different than the polymer polyol (1),

with the sum of the %'s by weight of polyols (1) and (2) totaling 100% by weight of (B);

in the presence of

(C) at least one blowing agent;

(D) at least one surf actant; and

(E) at least one catalyst.

18. The process of claim 17 , wherein (A) said polyisocyanate comprises greater than 50% by weight of toluene diisocyanate.

19. The process of claim 17 , wherein (A) said polyisocyanate comprises 100% by weight of toluene diisocyanate.

20. The process of claim 17 , wherein (A) said polyisocyanate is present in an amount of less than 65 pbw, based on 100 pbw of component (B).

21. The process of claim 17 , wherein (B) said isocyanate-reactive component has a solids content of at least 45% by weight, an overall hydroxyl number of the liquid, non-solids portion of at least 180, and has a functionality of about 2 to about 8.

22. The process of claim 17 , wherein (B)(2) said one or more second polyols is characterized by a hydroxyl number of 10 to 2000 and as having a functionality of at least 2.

23. The process of claim 17 , wherein (B) said isocyanate-reactive component comprises:

(1) at least 70% by weight of a polymer polyol having a solids content of at least 40% by weight, and in which the base polyol of the polymer polyol has a hydroxyl number of 70 to 600 and a functionality of 2 to 6; and

(2) no more than 30% by weight of one or more second polyols, with the second polyol having a hydroxyl number of 15 to 1500 and a functionality of 2 to 6.

24. The process of claim 17 , wherein (B) said isocyanate-reactive component comprises:

(1) at least 80% by weight of a polymer polyol having a solids content of at least 50% by weight, and in which the base polyol of the polymer polyol has a hydroxyl number of 100 to 600 and a functionality of 2 to 4; and

(2) no more than 20% by weight of one or more second polyols, with the second polyol having a hydroxyl number of 20 to 1000 and a functionality of 2 to 4.

25. The process of claim 17 , wherein (B)(2) comprises a polymer polyol having a solids content of no more than about 80% by weight, and in which the base polyol has a hydroxyl number of from about 10 to less than 70 and a functionality of at least two.

26. The process of claim 17 , in which (B)(2) is selected from the group consisting of polyether polyols, chain extenders and crosslinking agents.

27. The process of claim 17 , wherein (C) said blowing agent is present in an amount of from 0.5 to 10 parts by weight, based on 100 parts by weight of component (B) the isocyanate-reactive component.

28. The process of claim 17 , in which the base polyol of the polymer polyol (B)(1) has a functionality of >2.2.

29. The process of claim 17 , in which the resultant polyurethane foam has a density of greater than 0.7 pcf.

30. The process of claim 17 , in which the resultant polyurethane foam has adjusted 50% CFD of greater than 7.0 psi.

31. The process of claim 17 , in which components (A) through (E) are reacted via a one-shot process.

32. The process of claim 17 , additionally comprising the steps of:

(II) depositing the reaction mixture from (I) onto a suitable substrate, and

(III) allowing the reaction mixture to rise freely or to rise to a controlled height, to form a free-rise foam.

33. The process of claim 17 , additionally comprising the steps of:

(II) depositing the reaction mixture from (I) into a mold to fill the mold cavity, and

(III) allowing the reaction mixture to fully react to form a molded foam.