Polyurethanes, articles and coatings prepared therefrom and methods of making the same

1. An article comprising a polyurethane comprising a reaction product of components comprising:

(a) about 1 equivalent of at least one polyisocyanate;

(b) about 0.05 to about 0.9 equivalents of at least one branched polyol having 3 to 18 carbon atoms and at least 3 hydroxyl groups; and

(c) about 0.1 to about 0.95 equivalents of sorbitol, mannitol, and/or at least one diol having 2 to 18 carbon atoms,

wherein the reaction product components comprise less than about 5 weight percent of polyester polyol, polycarbonate polyol or polyether polyol and less than about 2 weight percent of amine curing agent on a basis of total weight of the components,

wherein, upon mixing, the reaction components are maintained at a reaction temperature of at least 110° C. for at least about 10 minutes, degassed, and reacted at a temperature of about 100° C. to about 140° C. for at least about 6 hours, and wherein the article is cured at a temperature of from about 120° C. to about 150° C. for a curing time period of from about 0.5 to about 72 hours, and

wherein the article has a Gardner Impact strength of from about 100 in-lb (11 Joules) to about 640 in-lb (72 Joules) according to ASTM-D 5420-04, wherein the Gardner Impact strength is measured after the curing time period.

2. The article according to claim 1 , wherein the article is selected from the group consisting of transparencies, optical articles, photochromic articles, ballistic resistant articles, and glazings.

3. The article according to claim 1 , wherein the article is an airplane transparency.

4. The article according to claim 1 , wherein the article is a curved article.

5. The article according to claim 1 , wherein the article is a flat article.

6. The article according to claim 1 , wherein the article is a molded article.

7. The article according to claim 6 , wherein the molded article is a curved article.

8. The article according to claim 6 , wherein the molded article is a flat article.

9. An article comprising a polyurethane comprising a reaction product of components comprising:

(a) about 1 equivalent of at least one polyisocyanate;

(b) about 0.1 to about 0.9 equivalents of at least one branched polyol having 3 to 18 carbon atoms and at least 3 hydroxyl groups; and

(c) about 0.1 to about 0.9 equivalents of sorbitol, mannitol, and/or at least one diol having 2 to 18 carbon atoms,

wherein the reaction product components comprise less than about 5 weight percent of polyester polyol, polycarbonate polyol or polyether polyol, less than about 2 weight percent of amine curing agent on a basis of total weight of the components, and

wherein, upon mixing, the reaction components are maintained at a reaction temperature of at least 110° C. for at least about 10 minutes, degassed, and reacted at a temperature of about 100° C. to about 140° C. for at least about 6 hours, and wherein the article is cured at a temperature of from about 120° C. to about 150° C. for a curing time period of from about 0.5 to about 72 hours, and

wherein the article has a Gardner Impact strength of at least about 200 in-lb (23 Joules) according to ASTM-D 5420-04, wherein the Gardner Impact strength is measured after the curing time period.

10. The article according to claim 9 , wherein the article is selected from the group consisting of transparencies, optical articles, photochromic articles, ballistic resistant articles, and glazings.

11. The article according to claim 9 , wherein the article is an airplane transparency.

12. The article according to claim 9 , wherein the article is a curved article.

13. The article according to claim 9 , wherein the article is a flat article.

14. The article according to claim 9 , wherein the article is a molded article.

15. The article according to claim 14 , wherein the molded article is a curved article.

16. The article according to claim 14 , wherein the molded article is a flat article.