The thermal properties, morphological structure and physical properties such as tenacity, elongation at break and crystallinity were investigated by Fourier Transform Infrared Spectroscopy(FTIR), W–angle X–ray Diffractometry (WAXS), Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) respectively. Also optical properties of fibers were studied by Reflection Spectrophotometer. Additionally other parameters such as cross section of fibers, distribution of nanoparticle in the spun fibers were also investigated. Antimicrobial tests were carried out using AATCC 100 test and ASTM E 2149–01 (shake flask) methods on the melt spun samples. The effect of parameters such as nanosilver content in the fibers, fibers fineness, percentage of the sheath of fibers on antibacterial properties of the sheath–core bicomponent fibers have been investigated. The results indicated that decreasing the percentage of sheath component of bicomponent fibers, increased the tenacity. Moreover increasing the amount of nano silver masterbactah, decreased the tenacity of the sheath–core bicomponent fibers slightly when compared pure fibers. The SEM and TEM results showed that the silver nanoparticles were not Agglomerated. The results of the DSC thermogram and X–ray diffraction indicated that the crystallinity of fibers decreases by increasing the amount of nanosilver. The results of antibacterial tests, show that the fibers with nano silver in sheath had excellent antibacterial properties even when silver content was very low.
