Preparation method of whitened microencapsulated red phosphorus flame retardant

The invention belongs to the technical field of flame-retardant material modification preparation, and particularly relates to a preparation method of a whitened microencapsulated red phosphorus flame retardant. The method comprises the following steps: (1) adding red phosphorus (RP) and an emulsifier into water, and mixing to obtain an RP emulsion; (2) dropwise adding a capsule raw material and absolute ethyl alcohol mixed solution into the RP emulsion, and continuously stirring to obtain a microencapsulated red phosphorus suspension; and (3) filtering, washing, drying and grinding the obtained microencapsulated red phosphorus suspension to obtain a microencapsulated red phosphorus finished product. According to the invention, the hydrolysis product titanium dioxide of the capsule material raw material is used as the wall material, and the RP is subjected to inorganic coating, so that the obtained microencapsulated red phosphorus has the advantages of high whiteness, low hygroscopicity, strong oxidation resi