Preparation and properties of continuously produced conductive UHMWPE/PANI composite yarns based on in-situ polymerization

In-situ polymerization should be a promising method for preparing polyaniline (PANI) composite conductive fibers, but using the conventional in-situ polymerization process to prepare conductive yarns continuously in a stepwise method is almost impossible. In this paper, a novel method based on in-situ polymerization was used to prepare conductive UHMWPE/PANI composite yarns continuously; using this method, aniline, oxidation and doping acid absorbed and reacted on the surface of the yarn to form a layer of electrical conductive polyaniline in air but not in the aqueous solution. The effects of the concentration of the reaction mixture on the structure and properties of the composite yarns were discussed. The results indicated that the electrically conductive polyaniline could form on the surface of the UHMWPE yarn, the content of polyaniline increased with the concentration of the reaction mixture. The thermal stability of the UHMWPE yarn decreased gradually after the conductive treatment with the increase of the content of polyaniline. The electrical conductivity increased before decreasing with the increasing concentration of the reaction mixture, and the electrical conductivity of the UHMWPE/PANI composite yarn peaked at 0.458 S/cm, exceeding that of the conductive fibers prepared using a conventional in-situ polymerization. The tensile strength and elongation at break for the UHMWPE yarn increased after the conductive treatment, while the initial modulus decreased.