Flame retardant tetra(0-propyl-phenylphosphinyl)glycoluril compound and preparation method thereof

The invention relates to a flame retardant tetra(0-propyl-phenylphosphinyl)glycoluril compound and a preparation method thereof. The structure of the compound is disclosed as the following formula. The preparation method comprises the following steps: while controlling the mol ratio of tetrachloroglycoluril to dipropyl phenylhypophosphite at 1:4-1:6, dropwisely adding the dipropyl phenylhypophosphite into a tetrachloroglycoluril-organic solvent solution by four times, and keeping the temperature at 100-110 DEG C to react for 5-7 hours; and purifying to obtain the product tetra(0-propyl-phenylphosphinyl)glycoluril. The compound provided by the invention is an excellent halogen-free phosphorus nitrogen synergic flame retardant, and can be used for flame retardancy of polyester PBT (polybutylene terephthalate), polyester PET (polyethylene terephthalate), polyvinyl chloride, polyurethane, epoxy resin, unsaturated resin and the like. The invention has the advantages of simple technique and low equipment investment, and can easily implement industrial production.