Nucleating agents

1. A method of increasing the crystallization rate of a thermoplastic polyester composition, comprising:

cooling a composition comprising a thermoplastic polyester and a nucleant from a temperature above the crystalline melting point of the thermoplastic polyester to a temperature below the crystalline melting point of the thermoplastic polyester, wherein the nucleant is a compound represented by the following chemical formula:

wherein each R 1 is independently H, NR 2 R 2 , OH, OR 2 , SR 2 , SOR 2 , SO 2 R 2 , CN, COR 2 , CO 2 R 2 , CONR 2 R 2 , NO 2 , F, Cl, Br, or I; each R 1 in Formula 4 is independently H, OH, OR 2 , SR 2 , SOR 2 , SO 2 R 2 , CN, COR 2 , CO 2 R 2 , CONR 2 R 2 , NO 2 , F, Cl, Br, or I; and

allowing the thermoplastic polyester to crystallize.

2. The method of claim 1 , wherein the thermoplastic polyester comprises an aliphatic polyester.

3. The method of claim 2 , wherein the aliphatic polyester is selected from the group consisting of polybutylene succinates, polycaprolactones, polyhydroxyalkanoates, polyglycolic acids, polylactic acids, and combinations thereof.

4. The composition of claim 2 , wherein the aliphatic polyester is a polyhydroxyalkanoate.

5. The method of claim 4 , wherein the polyhydroxyalkanoate is a polyhydroxyalkanoate homopolymer selected from the group consisting of poly-3-hydroxybutyrate, polylactic acid, polyglycolic acid, and poly-4-hydroxybutyrate.

6. The method of claim 5 , wherein the polyhydroxyalkanoate is poly-3-hydroxybutyrate.

7. The method of claim 4 , wherein the polyhydroxyalkanoate is a copolymer of 3-hydroxybutyrate and at least one co-monomer selected from the group consisting of 3-hydroxypropionate, 3-hydroxyvalerate, 3-hydroxyhexanoate, 3-hydroxyheptanoate, 3-hydroxyoctanoate, 3-hydroxynonaoate, 3-hydroxydecanoate, 3-hydroxydodecanoate, 3-hydroxydodecenoate, 3-hydroxytetradecanoate, 3-hydroxyhexadecanoate, 3-hydroxyoctadecanoate, 3-hydroxy-4-pentenoate, 4-hydroxybutyrate, 4-hydroxyvalerate, 5-hydroxyvalerate, and 6-hydroxyhexanoate.

8. The method of claim 7 , wherein the copolymer is poly 3-hydroxybutyrate-co-3-hydroxypropionate, poly 3-hydroxybutyrate-co-4-hydroxybutyrate, poly 3-hydroxybutyrate-co-3-hydroxyvalerate, poly 3-hydroxybutyrate-co-3-hydroxyhexanoate, poly 3-hydroxybutyrate-co-3-hydroxyvalerate-co-3-hydroxyhexanoate, or poly 3-hydroxybutyrate-co-3-hydroxyhexanoate-co-3-hydroxyoctanoate-co-3-hydroxydecanoate-co-3-hydroxydodecanotate-co-3-hydroxydodecenotate.

9. The method of claim 8 , wherein the copolymer is poly 3-hydroxybutyrate-co-4-hydroxybutyrate.

10. The method of claim 7 , wherein the 3-hydroxybutyrate is present in the copolymer in a range of about 60 to 98 weight percent, about 70 to 98 weight percent, about 80 to 98 weight percent, or about 90 to 98 weight percent.

11. The method of claim 2 , wherein the aliphatic polyester is polybutylene succinate or polybutylene succinate adipate.

12. The method of claim 1 , wherein the thermoplastic polyester comprises an aromatic polyester.

13. The method of claim 12 , wherein the aromatic polyester comprises a polyethylene terephthalate.

14. The method of claim 13 , wherein the polyethylene terephthalate comprises a co-monomer.

15. The method of claim 14 , wherein the co-monomer is an ether or amide or aliphatic monomer.

16. The method of claim 12 , wherein the aromatic polyester is a polybutylene adipate/terephthalate or a polymethylene adipate/terephthalate.

17. The method of claim 1 , wherein the nucleant is cyanuric acid.

18. The method of claim 4 , wherein the nucleant is cyanuric acid.

19. The method of claim 6 , wherein the nucleant is cyanuric acid.

20. The method of claim 9 , wherein the nucleant is cyanuric acid.