ECCM15 - 15 TH EUROPEAN CONFERENCE ON COMPOSITE MATERIALS, Venice, Italy, 24-28 June 2012 1 EFFECT OF CNT ON THE MECHANICAL PROPERTIES OF MELT SPUN PET/CNT NANOCOMPOSITE FIBERS S. A. Furquan 1 , K. Mezghani 1* , M. R. Farooqui 1 , F. Patel 1 , M. Atieh 2 1 Mechanical Engineering Department, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia 2 Chemical Engineering Department, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia *Mezghani@kfupm.edu.sa Keywords: Nanocomposites, CNT, PET, Fibers. Abstract A co-rotating twin screw extruder with 3 zones of mixing elements was used to produce nanocomposite fibers of polyethylene terapthalate (PET) and carbon nanotubes. The PET and the CNT materials were fed using two separately controlled feeders. The polymer was fed at the first entrance to the extruder; whereas, the CNT was fed at three different positions located along the extruder barrel. The results showed that an addition of 1 wt% CNT enhanced the mechanical properties of PET/CNT nanocomposite fibers. The yield strength, tensile strength, and toughness were increased by 80%, 51%, and 134%, respectively, in contrast to the mechanical properties of pristine PET fibers. The scanning electron microscope (SEM) images showed that the feeding position with three mixing zones gives the most uniform distribution of CNT and the best spinnability of the PET/CNT fibers. 1 Introduction Polymer composites are used in variety of industrial and household applications. Efforts are being made to increase the range of applications of polymer composites by modifying with organic and inorganic nanomaterials such as carbon nanotubes, carbon nanofiber, nanoclay, nanosilica and other nanomaterials. The blending of these organic and inorganic nanomaterials in polymeric matrix is not an easy task. The major hurdle in preparing these blends is the agglomeration of nanoparticles within the matrix [1-4]. It is very important to consider an effective mixing method to have a good dispersion of these nanomaterials within the polymer matrix. Several methods have been tried in literature to achieve effective mixing using different techniques. Some of the methods such as twin screw extrusion [4-9], melt compounding and kneading [5, 10, 11], ball milling or hand mixing [5], ultrasonic homogenizing [12] and rheomix mixer using roller type rotors [5] have been tried to obtain a good mixing of these organic/inorganic nanomaterials with the polymers. In the present work PET/CNT nanocomposite fibers are produced using melt extrusion technique. The article includes the investigation of the effect of CNT feeding position on the on the quality of PET/CNT nanocomposite fibers. Further, the morphology and mechanical properties of these fibers are discussed.