Abstract: A series of chrysotile nanotubes have been synthesized by hydrothermal method using MgO and SiO_2 as raw materials. The samples for different reactive time were characterized by Powder X-ray diffraction(XRD), scanning electron microscopy(SEM), high resolution transmission electron microscopy(HRTEM), infrared spectroscopy(IR). The XRD analysis indicated that the level of layers-curving increase gradually along with longer reactive time.The decreasing trend on the degree of chrysotile crystallinity is revealed by XRD and IR studies, with increasing reactive time. The out diameter、inner diameter and lengths of chrysotile nanotubes are 15-40 nm、6-9 nm and 50-300 nm by the SEM and TEM analysising, respectively.The growth mechanism of layers-curving of the chrysotile nanotubes under hydrothermal conditions is proposed on the basis the results of experiment.

Key words: A series of chrysotile nanotubes have been synthesized by hydrothermal method using MgO and SiO_2 as raw materials. The samples for different reactive time were characterized by Powder X-ray diffraction(XRD), scanning electron microscopy(SEM), high resolution transmission electron microscopy(HRTEM), infrared spectroscopy(IR). The XRD analysis indicated that the level of layers-curving increase gradually along with longer reactive time.The decreasing trend on the degree of chrysotile crystallinity is revealed by XRD and IR studies, with increasing reactive time. The out diameter、inner diameter and lengths of chrysotile nanotubes are 15-40 nm、6-9 nm and 50-300 nm by the SEM and TEM analysising, respectively.The growth mechanism of layers-curving of the chrysotile nanotubes under hydrothermal conditions is proposed on the basis the results of experiment.