Modified layered silicate novel barrier and shielding pigment and method thereof

Modified layered silicate novel barrier and shielding pigment, it is characterized by:

• it uses layered silicate with exchangeable anti-corrosion ions as a template, and uses metal oxides or their salts or hydroxides, inorganic acid or inorganic acid salt to synthesize nano-spherical phosphates, molybdates, borate or tungstate by liquid deposition, and by doping modification with rare earth cerium, strontium, lanthanum or praseodymium to obtain the pigment;
• specifically, the organic amine inhibitor was grafted with layered silicate by condensation reaction using phosphoric acid, and a metathesis reaction occurs between the metal oxide or hydroxide or its sulfates, nitrate and hydrochloride and the inorganic acid or inorganic acid salt, generate nanoscale phosphate, molybdate, tungstate or borate, deposit on the surface of layered silicate sheets, and select rare earth oxides or their sulfates, nitrates and hydrochloride for doping and modification;
• the preparation method of modified layered silicate novel barrier and shielding pigments includes the following steps:
• a. prepare metal oxides or their sulfates, nitrates and hydrochloride or hydroxide in 30-200 parts by weight, dissolve with 150-800 parts by weight of water, disperse in high speed, filtrate to remove coarse particles of impurities, replenish water to maintain flow capacity if viscosity is too high;
• b. prepare 10-40 parts by weight of organic amine corrosion inhibitor, 100-600 parts by weight of water, dissolve in 3-7 minutes, 20-80 parts by weight of 80-90% phosphoric acid, add and stir for 3-8 minutes;
• 40-150 parts by weight of layered silicate and 200-750 parts by weight of water to make silicate slurry, disperse the two at high speed for 25-35 minutes, stir at low speed for 1-3 hours, and add 50-220 parts by weight of inorganic acid or inorganic acid salt, add the slurry prepared in step a, stir for 20-40 minutes, grind for 25-35 minutes, add 3.5-21 parts by weight of rare earth oxides or their sulfates, nitrates and hydrochlorides, 3-22 parts by weight of inorganic acid or inorganic acid salt, continue to disperse at high speed, react for 3-5 hours, wash and centrifuge, dry and grind at 70-320° C.;
• the inorganic acid in step b is phosphoric acid, molybdic acid, tungstic acid or boric acid.