Default NASA CommQuest Silicone based Waterproofing of Porous Ceramics - Innovative Waterproofing Techniques Directions Please read the information provided on this technology. You may follow the links to additional information resources below. Besides adding unnecessary weight to the structure the excess water also increases its thermal conductivity. Additional problems develop when the ceramic is exposed to extremes in temperature.
Cold temperatures can cause the water to freeze causing damage.
On the other hand, if the ceramic is suddenly exposed to high temperatures the water can vaporize in an explosive fashion causing additional damage. It thus becomes very important to waterproof the ceramic to maintain its physical, chemical and electrical properties. This method is used to waterproof rigid and flexible porous ceramics. The waterproofing is achieved by treating the ceramic with an aqueous solution of Organopolysiloxane waterproofing agent followed by heat treatment that results in the waterproofed ceramic. The water soluble waterproofing agent is absorbed into the ceramic structure by capillary action and a uniform layer of the agent is deposited both on the exterior and interior surfaces of the material.