Abstract: The development of a modified method to produce heat treated twisted nanofibrous yarns using two oppositely
metallic spinnerets system is presented. This method allows the production of more uniform, stronger twisted poly
acrylonitrile (PAN) yarns. The novelty of this system permits for in-situ heat treating of the nanofiber yarns. The average
diameter of twisted nanofiber yarns is 340.65 μm with 5.8 CV%. The values of the initial modulus and stress of heat treated
yarns increase from 1.90 GPa and 61.30 MPa in untreated one to 4.51 GPa and 116.56 MPa, respectively. In order to quantify
the alignment of the nanofibers Fourier power spectrum (FPS) and image analysis were used. So the treated yarn shows more
degree of nanofiber alignments than the untreated one.
Keywords: Electrospun yarn, Mechanical properties, Heat setting, Fourier power spectrum, Image analysis