Bispyribac-sodium dispersible oil suspended agent and preparation method thereof

The invention relates to an optional stem and leaf herbicide for a paddy field and a preparation method thereof, and in particular relates to a bispyribac-sodium dispersible oil suspended agent and a preparation method thereof. The bispyribac-sodium dispersible oil suspended agent comprises the following components in percentage by mass: 10-20 percent of bispyribac-sodium, 2-30 percent of emulsifier, 0.2-5 percent of a wetting agent, 0.3-5 percent of a dispersing agent, 0.5-4 percent of a thickening agent, 0.01-5 percent of a defoaming agent, 0.1-1.5 percent of a pH regulating agent, and the balance of an oil-based solvent. The preparation method comprises the following steps: adding the emulsifier, the wetting agent, the dispersing agent, the thickening agent, the defoaming agent and the pH regulating agent into the oil-based solvent, mixing and stirring; adding the bispyribac-sodium drug under stirring of a high-speed shearing machine at a rotating speed of 1,500-10,000 revolution/minute, and shearing for 1