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Vertically aligned carbon nanotubes (VA-CNTs) were successfully grown on silicon substrates by atmospheric pressure chemical vapor deposition at 750∘C using acetylene as a carbon source and Fe-Co nanoparticle thin films as a cocatalyst. Preparation of the cocatalyst was operated by an economical sparking process. A small amount of water vapor was introduced into the reactor by controlling diffusion by heated water in a flask. The CNTs were characterized by scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. The VA-CNTs were obtained only when the water vapor fraction in the introduced gas was in the range of 310–440 ppm. The length of the VA-CNTs reached 0.8 mm with a growth rate of 17 μm/min. Moreover, D/G-band ratio suggests that the optimum fraction of water vapor decreases defects in CNTs.

Silver zirconium phosphate (AgZrP) was incorporated into nylon 6,10 fibers by using a twin screw extruder to produce antimicrobial fibers. Monofilament fibers with various degrees of AgZrP loading were prepared by the melt-spinning process. The surface concentration of AgZrP particles was found to be dependent on AgZrP loading. A poor interface between AgZrP and the polymeric matrix was observed, however, it did not affect the drawn process. The presence of AgZrP particles did not disturb the structure and slightly effected to the mechanical properties of the nylon fiber. The fiber with the highest draw ratio showed the highest degree of polymer chain orientation, a higher tensile strength and a higher modulus. The antimicrobial effect started when the silver ion concentration was high enough, The AgZrP fiber showed the highest antimicrobial effect on S. mutans, L. Casei, S. aureus, and C. albicans at 10, 15, 10, and 15%, respectively. The AgZrP fibers showed the significant antimicrobial effect on three strains of microorganisms except S. aureus. Antimicrobial activities of AgZrP were demonstrated and the results showed that AgZrP incorporated into the matrix of nylon 6,10 fibers can improve their antimicrobial property.