关键词: 硫酸钙晶须, 二氧化硅, 包覆改性, 分散性

Abstract: With sodium silicate as silicon source，dense silica nano-films were coated on the surface of calcium sulfate whisker （CSW） by liquid deposit method to modify it inorganically.Silica-coated CSW and mechanism were characterized by scan- ning electron microscope（SEM），X-ray powder diffraction（XRD），and Fourier transform infrared spectroscopy（FT-IR） etc.. Results showed that when the reaction temperature was 90 ℃ and pH=9，a dense silica layer coated on the surface of CSW uniformly.The zeta potential was obviously improved after coating.When SiO2-CSW was applied in thermoplastic elastomer of EPDM/PP，it could effectively improve the degree of dispersion of CSW.

Key words: CaSO4 whisker, silica, coating modification, dispersibility