1. Formation
2. polyhydroxybutyrate
3. These
4. Polymers
5. Are
6. synthesized
7. many
8. they
9. themselves
10. a nutrient
11. limited
12. environment
13. With
14. An
15. Available
16. Up
17. Be
18. Granules
19. Composed
20. predominantly
21. these
22. Copolymers
23. Possess
24. properties
25. thermoplastics
26. biodegradable
27. which
28. has
29. made
30. them
31. potentially
32. attractive
33. as
34. alternatives
35. to
36. the less
37. environmentally
38. friendly,
39. petroleum-based