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Laser melt electrospinning, which adopts CO2 laser beam to melt polymer, is a novelmethod compared to other melt devices. In present paper, we used laser melt electrospinningtechnology to prepare poly（ε-caprolactone） （PCL）, polylactide （PLLA）, and poly（ethyleneterephthalate） （PET） fibers. The effects of electrospun parameters on the fiber diameters wereinvestigated. The physi-chemical properties of the fibers also were studied. In addition, weprepared PLLA/nHA fibers with the modification of incorporating HA nanocrystalline particles.PET/SiO2 composite fibers were also prepared by laser melt electrospinning.The scanning electron microscopy （SEM） results showed that, for the PCL, PLLA, and PETfibers, the fibers diameter tended to decrease as laser current increased. For PET fibers, the fibersdiameter tended to increase as the applied voltage increased, while it is no statistically significanteffect on the PCL and PLLA fibers diameter. The results of orthogonal design showed the orderof significance levels on PLLA fibers as follows: applied voltage, laser current, collectordistance, and MFR for the fiber diameter. X-ray diffraction （XRD） and differential scanningcalorimetry （DSC） results showed that the crystallinity of melt electrospun PCL mats is around60%. However, PLLA and PET fibers exhibited an amorphous phase, respectively. Fouriertransform infrared （FTIR） test showed that the molecular chain structure of the electrospunPLLA fibers had not remarkable changed. The EDS analysis confirmed the presence ofnanoparticles in the PLLA/nHA and PET/SiO2 fibers matrix, respectively. The degradation ofPCL molecular chains often occurs in the melt electrospinning process due to mechanicalscission and thermal degradation using an Ubbelohde viscometer. The mechanical test showedthat, for PCL, PLLA, PET mats, the average tensile strength was 1.96±0.1MPa, 1MPa, and1.3MPa, respectively. The breaking strain was 122.2±45%, 6%, and 5%, respectively.
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