Investigation of polylactide/poly(ε-caprolactone)/multi-walled carbon nanotubes electrospun nanofibers with surface texture

Abstract

Multi-walled carbon nanotubes (MWCNTs) acting as compatibilizer reduce the sizes of poly(ε-caprolactone) (PCL) phase in polylactide (PLA) matrix and improve the compatibility of the immiscible blend. However, the influence of MWCNTs on the compatibility of PLA/PCL nanofibers has not been investigated. In this work, the immiscible PLA/PCL/MWCNTs composite nanofibers with parallel line surface texture were successfully fabricated by electrospinning. The formation mechanism of secondary oriented structure on nanofiber surface was discussed, and the effects of MWCNTs on the phase structure, compatibility, crystallization behavior and mechanical property of PLA/PCL blend were systematically investigated. The dispersion of PCL phase domains in the PLA matrix was obviously improved with the addition of MWCNTs, which was verified by scanning electron microscopy (SEM), polarized optical microscopy (POM) and atomic force microscope (AFM). In addition, amphiphilic MWCNTs also acting as heterogeneous nucleation improved the crystallization degree of PLA in the blend, as demonstrated by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The mechanical tests showed that MWCNTs played a role in reinforcement improving mechanical properties of the blend. The results of proliferation revealed that the nanofibrous scaffold with MWCNTs had no toxic effect on the proliferation of NIH3T3 mouse fibroblasts cells, making them potential substrates for tissue engineering.