(639g) Thermal Properties and Crystallinity of Poly (?-caprolactone) (PCL) and MgO Incorporated PCL Nanofibers

Magnesium (Mg) is highly interested in biomedical applications, especially tissue engineering. Mg and a number of its alloys are effective because they exhibit excellent in vivo biocompatibility, biodegradability, and during degradation, it releases Mg ions (Mg²⁺) with the potential to improve tissue repair. In this study, the physicochemical properties of pure PCL and magnesium oxide (MgO) nanoparticle incorporated PCL (MgO/PCL) nanofiber composite were analyzed by Fourier-transform infrared spectroscopy (FTIR), mechanical tensile testing, differential scanning calorimetry (DSC), and X-ray diffractometry (XRD). DSC is a tool used to observe the changes of polymers with the aspect of heating and cooling. DSC curve gives thermal properties such as melting temperature (T_m), crystallization temperature (T_c), percent of crystallinity, heat capacity (C_p), and the latent heat of polymers.

The investigation was made as a function of cooling rates from 0.5 – 30 K/min to observe the crystallization and melting behavior of poly (ɛ-caprolactone) and MgO incorporated PCL nanofibers using DSC-3 from Mettler Toledo. The result shows that the crystallization temperature increased as the cooling rate decreased but with little melting temperature dependence on the cooling rates. Furthermore, the nanofibers' structural analysis and chemical structure were investigated using XRD and FTIR, respectively. The change in crystallinity using XRD indicates a change in chain mobility and might translate to higher mechanical properties. A PCL nanofiber electrospuned for three minutes has a maximum tensile strength of 5.5 MPa and is highly stretchable. The contact angle of PCL and MgO-PCL nanofibers are 64°and 79o, respectively. In conclusion, polymeric electrospun nanofibers reinforced with nanoparticles (NPs) present many potential applications since they combine the flexibility and porosity of electrospun polymeric fibers with the functional properties of Mg nanoparticles. The detailed results will be discussed in the presentation.