The invention relates to a highly-heat-resistant liquid
silicate water-based heat-insulating
coating material and a preparation method thereof. The
coating material comprises the following components by weight percent: 45% to 60% of liquid
silicate, 11% to 16% of
ion exchange water, 3% to 5% of alkoxy
silane, 0.5% to 1.5% of
silicate nanopowder, 1% to 2.7% of
wetting agent, 1% to 3% of mineral
cellulose, 5% to 10% of ludox, 1.5% to 3.5% of ultrafine
silica nanoparticle powder, 5% to 9% of
sodium borate glass hollow spheres, 0.3% to 1.0% of
phosphoric acid aqueous solution and 5% to 10% of
inorganic filler. The preparation method comprises the following steps of: evenly mixing the liquid silicate with the
ion exchange water; sequentially adding the alkoxy
silane and the silicate nanopowder; sequentially adding the
wetting agent, the mineral
cellulose and the
inorganic filler; adding the ludox and the ultrafine
silica nanoparticle powder; adding the
sodium borate glass hollow spheres; and finally, slowly adding the
phosphoric acid aqueous solution, thereby obtaining a target product. The
coating material provided by the invention is excellent in
water resistance,
heat resistance and heat insulation as well as simple in preparation process, broad in
raw material source and low in cost, thereby being suitable for large-scale industrial production.