Dampproof method for porous ceramic material containing silicon hydroxyl

The invention discloses a damproof method for a porous ceramic material containing silicon hydroxyl. The method comprises the following steps of: firstly immersing porous ceramic containing silicon hydroxyl in absolute ethyl alcohol for 30-60 minutes; putting the baked porous ceramic containing silicon hydroxyl in a resistance furnace; heating the porous ceramic containing silicon hydroxyl to 350-450 DEG C from room temperature within 150-170 minutes, and then preserving heat for 150-280 minutes; then heating the porous ceramic containing silicon hydroxyl to 650-800 DEG C within 70-100 minutes, and then preserving heat for 20-100 minutes; cooling porous ceramic containing silicon hydroxyl in the furnace and taking the porous ceramic containing silicon hydroxyl out of the furnace when the temperature is reduced to room temperature; then immersing the porous ceramic containing silicon hydroxyl in a silane compound for 7-12 hours in a sealed manner and pouring out the solution at the upper layer; finally washing with absolute ethyl alcohol. The damproof method has the characteristics that the silicon hydroxyl-containing porous ceramic is immersed in a silane compound, and then hydrophilic silicon hydroxyl Si-OH on the surface of the porous ceramic is converted into hydrophobic Si-CH3, so that the porous ceramic has strong dampproof performance and low moisture absorption rate reduced to 0.1-0.9%.