Summary of thermal characteristics and curve fitting parameters of PCL/PLGA fibers.
| Formulation | Thermal Characteristics | Power Law Paramaters1 | |||||
|---|---|---|---|---|---|---|---|
| Tm (°C)2 | ΔH (J/g)3 | Tg (°C)4 | CTFV (%)5 | CPCL (%)5 | k | n | |
| PCL Blank | 57.5 | 57.2 | n.d. | n.d. | 49.1 | n/a | n/a |
| PLGA Blank | n.d. | n.d. | 53.8 | n.d. | n.d. | n/a | n/a |
| PCL + 15 wt% TFV | 58.8 | 61.2 | n.d. | 1.7 | 66.2 | n/a | n/a |
| PCL/PLGA 80:20 + 15 wt% TFV | 58.2 | 43.0 | n.d. | 1.4 | 35.9 | n/a | n/a |
| PCL/PLGA 60:40 + 15 wt% TFV | 57.4 | 33.5 | n.d. | 1.8 | 24.2 | 26.6 | 0.19 |
| PCL/PLGA 40:60 + 15 wt% TFV | 57.4 | 22.0 | n.d. | 1.6 | 10.2 | 26.7 | 0.29 |
| PCL/PLGA 20:80 + 15 wt% TFV | 56.3 | 0.5 | 45.1 | 0.9 | n.d. | 12.1 | 0.29 |
| PLGA + 15 wt% TFV | n.d. | n.d. | 46.3 | 1.6 | n.d. | 5.0 | 0.38 |
Power law parameters derived from power law equation: Mt/Mtotal = ktn, where k and n describe the characteristics of macromolecular network and release mechanism, respectively.36,40,41
Tm = Melting temperature of PCL in final fiber formulation.
ΔH = Enthalpy of PCL melting peak. Value listed is the integration under the curve of PCL melting peak.
Tg = Glass transition temperature of PLGA in final fiber formulation.
Relative TFV and PCL crystallinity calculated by integrating area under the melting curve (ΔH) of each and comparing to pure TFV powder and PCL pellets, respectively. Crystallinity values were also calculated relative to the mass content of each component in the final fiber formulation.