Melt Electrospinning of Poly(ε-caprolactone)/Poly(ethylene oxide)/Poly(ethylene glycol) Blend: Effects on Structure and Cellular Compatibility.

This work aims to investigate the effects of the melt electrospinning process on the properties of ternary blend poly-(ε-caprolactone)/poly-(ethylene oxide)/poly-(ethylene glycol) (PCL/PEO/PEG) fibers. The utterly different morphology of the specimens before and after melt electrospinning acknowledges the significant effect of melt electrospinning on the sample's properties. However, it does not chemically alter the samples. The Scanning Electron Microscope (SEM) images showed that PEO and PEG behave differently in the PCL matrix, producing distinctly different morphologies in the respective binary blend fibers. Differences in morphology also lead to differences in the crystallization behavior of the specimen. Wide-angle X-ray diffraction (XRD) and differential scanning calorimetry (DSC) also reveal that although PEO and PEG are fundamentally the same polymer with different molecular weights, their behaviors in the PCL matrix are entirely different; PEG mostly remains in the amorphous state, while PEO can form its crystalline structure. Hence, the final morphology of the ternary melt electrospun fiber is a combination of the morphology of PCL/PEO and PCL/PEG binary blends. Preliminary biological tests showed that the porosity created by the removal of the PEO and PEG hydrophilic phases improved fibroblast metabolic activity, highlighting the potential of this system for further investigation in bone tissue engineering applications.