Ammonium polyphosphate, montmorillonite nano complex and preparation thereof

The invention relates to an ammonium polyphosphate and montmorillonite nano compound and a preparation method thereof, which belong to the phosphorous compound preparation, composition, modification and crystalline control field. The method for preparing the nano compound comprises the following steps: montmorillonite is added during the preliminary stage of the process of general preparation of ammonium polyphosphate; ammonia is passed through when the temperature is raised to between 150 and 300 DEG C; heat preservation is performed when the temperature is raised to between 300 and 350 DEG C; and then the ammonium polyphosphate and montmorillonite nano compound are obtained after continuous ammoniation for 30 to 200 minutes. The preparation method controls the purity of an I-type polyphosphoric acid in the product through addition of a specific amount of the montmorillonite; the ammonium polyphosphate completely off a silicate slice of the montmorillonite; and nano-dispersion is formed in the ammonium polyphosphate, and then the ammonium polyphosphate and montmorillonite nano compound is obtained. The nano compound reduces the water solubility of the ammonium polyphosphate, has the function of improving the flame-retardant effect in inflaming retarding of polymer materials, and has the advantages of simple preparation technology and raw materials and low cost.