Granular stabilizer for chlorine-containing polymers and process for preparation thereof

摘要

Disclosed is a granular stabilizer for chlorine-containing polymers, which is formed by granulating a hardly fusible or infusible powdery stabilizer for chlorine-containing polymers or a mixture of said powdery stabilizer with a powdery stabilizer aid through an organic solid binder or dispersion medium, wherein respective primary particles of said powdery stabilizer or said powdery mixture are surface-treated with the organic solid binder or dispersion medium in an amount of 2 to 15 parts by weight per 100 parts by weight of said powdery stabilizer or said powdery mixture, which is smaller than the critical liquid absorption of said powdery, and said primary particles are granulated into particles having an average particle size of 0.1 to 2 mm by fusion bonding of the surface treatment layers of the organic solid binder or dispersion medium. This granular stabilizer is prominently excellent in the dispersibility in a chlorine-containing polymer, the uniformity of the composition, the scattering resistance, the flowability and the blocking resistance, though the starting powdery stabilizer is granulated with a much reduced amount of the solid binder or dispersion medium.