Research on Mechanical and Thermal Properties of 3-hydroxybutyrate-co-4-hydroxybutyrate [P (3HB-4HB)] and the Preparation for Fiber

3- hydroxybutyrate-co-4-hydroxybutyrate[P (3HB-4HB)] is biodegradable and biocompatible which is synthesized by bacterium as energy reserve. The P (3HB-4HB) fiber that prepared by melt spinning will meet the requirements of suture. In our research, capillary rheometer, differential scanning calorimeter (DSC) and TGA are used to investigate its rheology and thermal behaviors. The technology of melt spinning is also studied and the P (3HB - 4HB) fiber with a certain mechanical property is obtained successfully. Electronic velocimeter and electronic single end yarn strength tester are applied to investigate the mechanical property of the fiber. We also simulated a disinfection techniques that is commonly used in medicine-ultravioletirradiation. Besides, the variation of the mechanical properties of the disinfected fibers and undisinfected ones was investigated. The rheology result shows that P (3HB- 4HB) melt is pseudoplasticfluid and is sensitive to temperature and shear rate. DSC curve shows that the T(g) of P (3HB-4HB) is - 10 degrees C and the endothermic peak of melting appears at 100 similar to 120 degrees C. It can be seen from TGA curve that P(3HB-4HB) decomposed rapidly over 205 degrees C. The result of velocimeter test indicates that molecular chain oriented axially after being drawn. And the test of fibre tuft strength shows that the fiber strength is a little bit low while the rebound resilience is acceptable. The mechanical property of the fiber fell slightly after disinfection. But it will meet the requirements of suture after adjusting the preparation process appropriately.