Electrospinning of composite fibers with core-shell structure and self-healing properties

In this work, we successfully investigate the composite fibers with core-shell structure via electrospinning method and their self-healing properties using heat as source. Core-shell fibers are prepared by coaxial electrospinning method using thermoset epoxy as core solution and thermoplastic PCL as shell solution (20 wt%). The morphology of composite fibers is characterized through scanning electron microscopy, which shows the resultant fibers are uniform and smooth, and the diameter range is from 1 μm to 2 μm. Scanning electron microscopy (SEM) that is carried out to analyse the structure of composite fibers proves epoxy/PCL nanofibers with core-shell structure and the diameter of inner fiber is about 300 nm to 600 nm. Comparing with PCL nanofiber membrane, the epoxy/PCL composite membrane keeps the fiber morphology after heat treatment at 60 ℃. In addition, the macroscopic scratch can effectively realize self-healing process with a high speed and the fiber structure is not destroyed when the specimen is heated above the transition temperature. It is significant that these properties bring the epoxy/PCL films as functional coatings to various applications.