Effect of Microfiber Reinforcement on the Morphology, Electrical, and Mechanical Properties of the Polyethylene/Poly(ethylene terephthalate)/ Carbon Nanotube Composites

In situ microfiber reinforced conductive polymer com-posites consisting of high-density polyethylene (HDPE), poly(ethylene terephthalate) (PET), and multiwalled car-bon nanotube (CNT) were prepared in a twin screw ex-truder followed by hot stretching of PET/CNT phase in HDPE matrix. For comparison purposes, the HDPE/PET blends and HDPE/PET/CNT composites were also pro-duced without hot stretching. Extrusion process pa-rameters, hot-stretching speed, and CNT amount in the composites were kept constant during the experi-ments. Effects of PET content and molding tempera-ture on the morphology, electrical, and mechanical properties of the composites were investigated. Mor-phological observations showed that PET/CNT micro-fibers were successfully formed in HDPE phase. Elec-trical conductivities of the microfibrillar composites were in semi-conductor range at 0.5 wt % CNT content. Microfiber reinforcement improved the tensile strength of the microfibrillar HDPE/PET/CNT composites in comparison to that of HDPE/PET blends and HDPE/ PET/CNT composites prepared without hot stretchin