Preparation method of hydrophobic aluminum phosphate

[0017] A preparation method of hydrophobic aluminum phosphate, adding 20 g of aluminum phosphate with particle diameter 99%. The water contact angle of modified aluminum phosphate is 145°, while the contact angle of unmodified aluminum phosphate with water droplets is almost 0°. It can be seen that the modified aluminum phosphate changed from hydrophilic and oleophobic to hydrophobic and lipophilic. Put equal amounts of modified aluminum phosphate and unmodified aluminum phosphate in a constant temperature and humidity environment (40 °C, 80% RH), record the changes in their respective weights, and compare their moisture absorption rates. The moisture absorption rate of unmodified aluminum phosphate 7d was 7.25%, and the moisture absorption rate of modified phosphoric acid 7d was 0.32%, and its moisture resistance was greatly improved. Infrared spectroscopy studies showed that the infrared spectra of the samples before and after modification did not change significantly, indicat

[0019] A preparation method of hydrophobic aluminum phosphate, adding 20 g of aluminum phosphate with particle diameter 99%. The water contact angle of the modified aluminum phosphate is 130°. The infrared spectrum study showed that the infrared spectrum of the samples before and after modification did not change significantly, indicating that there was no chemical bonding between the polymethyltriethoxysilane and the groups on the surface of aluminum phosphate to form new chemical bonds, but physical adsorption. The aluminum phosphate powder is coated on the surface of the aluminum phosphate powder in a way to form a monomolecular film, which makes the surface of the aluminum phosphate powder organic and has strong hydrophobicity.

[0021] A preparation method of hydrophobic aluminum phosphate, adding 20 g of aluminum phosphate with particle diameter <80 μm into a 150 mL three-necked flask, then placing the three-necked flask in a constant temperature water bath, installing a reflux condensing device, then heating to 50 ° C, rapidly adding 2.0 g methyltriethoxysilane, and after mechanical stirring for 150 min, the sample was taken out and dried for 30 min to obtain hydrophobic aluminum phosphate.